Showing papers in "International Agrophysics in 2020"

Soil organic carbon physical fractions and aggregate stability influenced by land use in humid region of northern Iran

Abstract: *Corresponding author e-mail: ayoubi@cc.iut.ac.ir A b s t r a c t. The present study was executed in order to examine the influences of land use change on aggregate stability and soil organic carbon fractions in the humid region of the north of Iran. The study area featured three land uses which included natural Hyrcanian forest, tea plantation and paddy rice cultivation. One hundred soil samples were taken from the 0-10 cm layer in a grid pattern to allow for variations in the study area as much as possible in summer 2016. The results revealed that land use change significantly altered the physical and chemical characteristics of the soil, as the highest values of soil organic carbon and complexed organic carbon, and the lowest values of pH, calcium carbonate equivalent and bulk density, were observed in the natural forest. The greatest percentage of macro-aggregates was found in the natural forest followed by the tea plantation. Particulate organic carbon and soil organic carbon associated with clay and silt particles as well as soil organic carbon associated with all aggregate fractions showed the following trend: natural forest > tea plantation > rice cultivation. Overall, our results confirmed the importance of forest soils in C sequestration and the vital role played by soil organic carbon in soils to improve soil quality indicators and aggregation. K e y w o r d s: Hyrcanian forest, tea plantation, paddy rice, complexed organic carbon

Effect of extrusion-cooking conditions on the pasting properties of extruded white and red bean seeds

Abstract: Department of Thermal Technology and Food Process Engineering, University of Life Sciences in Lublin, Głęboka 31, 20-612 Lublin, Poland Department of Machinery Exploitation and Production Process Management, University of Life Sciences in Lublin, Głęboka 28, 20-400 Lublin, Poland Institute of Agrophysics, Polish Academy of Sciences, Doświadczalna 4, 20-290 Lublin, Poland Department of Agrobiotechnology, Koszalin University of Technology, Racławicka 15-17, 75-620 Koszalin, Poland Department of Physics, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland

Fish pond sediment from aquaculture production – current practices and the potential for nutrient recovery: a Review

Abstract: Faculty of Infrastructure and Environment, Institute of Environmental Engineering, Częstochowa University of Technology, Brzeźnicka 60A, 42-200 Częstochowa, Poland Institute of Biosystems Engineering, Poznań University of Life Science, Wojska Polskiego 50, 60-637 Poznań, Poland Faculty of Mechanical Engineering and Computer Science, Department of Polymer Processing, Częstochowa University of Technology, Armii Krajowej 19C, 42-200 Częstochowa, Poland

Field phenotyping of plant roots by electrical capacitance – a standardized methodological protocol for application in plant breeding: a Review

Abstract: The impact of most agricultural interventions (fertilization, irrigation, tillage) on crop growth and yield is mediated via the plant root system. Despite the essential role of the root system in determining attainable yields, roots have been historically overlooked as the hidden half of plants (Manske and Vlek, 2002; Waisel et al., 1991) and rarely targeted by agricultural crop improvements. With a higher frequency of drought in the context of climate change, and considering that water limitation is a major yield-limiting factor that is increasingly prevalent in temperate regions, plant breeding efforts have started to search for approaches that integrate the root system into the stress tolerance portfolio for trait-based crop improvement. There are several lines of evidence, which show that targeting the root system in the breeding process is highly promising for improving yield stability and crop performance in stress inducing environments. Some biologists, physiologists and breeders involved in plant root research consider the root system to be the key to a second green revolution, which does not rely on expensive inputs (e.g., Gewin, 2010). © 2020 Institute of Agrophysics, Polish Academy of Sciences Review T. STŘEDA et al. 174 Root systems for crop improvement – which trait to select for? The measurement of root characteristics is made difficult by the environment in which the roots develop. In fact, the size of the roots has not been used as a criterion for selection in practical breeding efforts (with the exception of root crops – sugar beet, carrot, etc.), although every new selection criterion initially shows a prompt response to selection as a rule. A rare practical outcome of this was the cultivation of wheat with reduced hydraulic conductivity of the vessels of the root system xylem in Australia’s arid climate (Richards and Passioura, 1989). An important question is which characteristics should be selected by breeders to obtain drought-tolerant plants. Selecting a suitable variety (based on the root system properties) for a specific area may be the key to a grower’s success. For example, deep-rooted varieties may be successful in dry years in soils with a higher water table. Gregory et al. (1978) found that only 3% of the total wheat root biomass occurred at a depth of 1 m, and this small portion provided up to 20% of the water needed for transpiration during the summer months. Kirkegaard et al. (2007) reported an increase in the grain yield of wheat by 59 kg ha per 1 mm of water delivered to a layer of 1.35-1.85 m during drought stress after flowering. Additionally, the topology of the root system, e.g., the different branching angles of the seminal roots in wheat (Manschadi, 2006), is related to the water uptake efficiency. A larger root system is considered to be an advantage, especially in the absence of sufficient water and nutrients, in a less fertile environment and in organic farming (Comas et al., 2013; Svačina et al., 2014), for enabling a more effective use of the nutrients from the soil, and thus lowering the contamination of the environment with unused nutrients, especially nitrogen and phosphorus (Gewin, 2010; KlimekKopyra and Rębilas, 2018). However, a higher root density did not always lead to an increase in nitrogen consumption (Wendling et al., 2016; Feng et al., 2016; Herrera et al., 2010). When comparing old and modern wheat varieties, Aziz et al. (2017) discovered that the root length density and total length of the root system decreased with ongoing breeding processes, but the efficiency of nitrogen uptake increased. Genotypes with superior root characteristics for efficient nutrient uptake should be developed in breeding programmes to increase grain yield and to minimize nitrate leaching (Ehdaie et al., 2010; Robinson et al., 2018), and appropriate phenotypes must be precisely identified for intentional breeding. Despite improvements in molecular technologies, fast and accurate phenotyping remains the major bottleneck to enhancing yield gains in water-limited environments (Richards et al., 2010). However, the shallow topsoil profiles of stony soils are inappropriate for deep-rooted varieties. Blum (2005) considers plants with a deep reaching extensive root system to be ill suited for conditions of rapid drying of the upper layer of the soil, which (by its mechanical properties) prevents the pronounced proliferation of roots. Growth is then curtailed, so that the genetic potential for long roots remains unused. In contrast, Richards (1991) stated that, for some environments, the formation of fewer roots in the upper soil layer may be an effective adaptation to drought. This could be related to the conclusions of Campos et al. (2004), who investigated the water obtained by the root system of old and modern varieties of maize. The old varieties showed a higher depletion of water predominantly from the upper parts of the soil profile. In particular, the depletion of water in the soil prior to the beginning of flowering was the reason for a more pronounced decline in the yield of older varieties compared to that of modern hybrids. The “Green Revolution” resulted in dwarf varieties of wheat capable of responding to higher fertilizer inputs, but they failed to reach resource-poor farmers. Crossing early green revolution wheat varieties, with an F2 of Norin 10 or Brevor, reduced root biomass. Later generation, semi-dwarf wheat showed a genetic variation in root biomass, but some generations exhibited a further reduction in root size (Waines and Ehdaie, 2007). From this point of view, the optimal regionalization of varieties with a larger root system is essential. Optimally, it is also desirable to take into account the root system morphology of a particular variety (the depth of the root system) or the dynamics of root growth during vegetative growth. Significant correlations between the root system size of barley in the stage of stem elongation during moderate drought stress and the seed vigour of progenies were found by Vintrlíková et al. (2015). It is likely that the increase in the root system of parents during drought stress conditions has enabled the rapid growth of the roots of progenies at the beginning of the vegetation period. However, a large sized root system is not always a great advantage. For example, if drought does not occur, then the development of a larger root system was an unnecessary investment for the plant at the expense of other photosynthetic products. The precise targeting of a variety to a particular area of cultivation may serve as the basis for the success and economic prosperity of farmers. For an improved exploitation of the available water, an adequate distribution of roots in the soil profile is preferable to a higher dry matter content of the roots (Bänziger et al., 2000). In cereals, root densities of 1.0-1.5 cm cm are required for the plant to extract the available water from the soil (Passioura, 1980; Vamerali et al., 2003). Lynch (2013) characterized the maize ideotype for its optimal uptake of water and mobile nutrients as steep, cheap and deep. This promotes the phenotypic or genotypic selection of a larger (deeper) root system in cereals. Fitter (2002) reported that high values of SRL (specific root length; root length per root weight unit) indicates the high ability of the roots to obtain nutrients. Similarly, Gonzalez-Dugo (2010) reported that the availability of FIELD PHENOTYPING OF PLANT ROOTS – A STANDARDIZED METHODOLOGICAL PROTOCOL 175 nitrogen is largely determined by root density. Palta et al. (2011) demonstrated significantly higher nitrogen and water absorption in wheat lines with a more vital root system at a depth of up to 0.7 m. Herrera et al. (2010) described the importance of the fast growth of the roots in deep soil layers at the beginning of the vegetation period, which may lower nitrogen losses through leaching. The fast growth of the root system of field crops is vital in order to prevent nitrates from leaching to deeper layers of the soil profile, however, the role of the root system in nitrogen uptake efficiency is still a point of controversy (Palta and Watt, 2009). A larger investment by a crop in fine roots that are deeper in the soil and fewer roots in surface layers would improve yields by allowing plants to access additional resources (King et al., 2003). Bertholdsson and Kolodinska Brantestam (2009) showed the importance of early vigour for drought tolerance and the development of finer roots in modern barley cultivars. It may be concluded that there is a large variation in root system characteristics and the functional strategies of plants within a given species. This is, on the one hand, a positive finding (varietal selection for superior root system traits is possible). On the other hand, it is necessary to factor in varietal differences in the creation and interpretation of experiments. Being critical to the integrity of the plant, the root system parameters affect the efficiency of the whole plant. Roots are very sensitive to soil conditions and are often the first organ of a plant that responds to stress. The adaptability of the root system confirms the excellent ability of roots to change their morphological properties to achieve the optimal growth of the whole plant. With a degree of generalization, it may be stated that deep-rooted varieties can be recommended in areas with a high water retention capacity in the subsoil. Varieties with a large, shallow root system may be recommended in drier areas with regular, lower amounts of precipitation, during which only the upper layer of the soil profile is moistened (Tron et al., 2015). The field phenotyping gap An ideal method for evaluating root systems should allow the researcher to obtain a detailed characterization of a wide range of root system parameters with a sufficiently large number of measurements. Unfortunately, a universal, inexpensive, reliable and

Determination of mechanical properties for wood pellets used in DEM simulations

Abstract: *Corresponding author e-mail: eutiquio.gallego@upm.es **This work was supported by the Spanish Research State Agency via the research project “Study of the structural behaviour of corrugated wall silos using Discrete Element Models (SILODEM)” (Grant No. PID2019-107051GB-I00 / AEI / 10.13039/501100011033, 2020 2023). A b s t r a c t . Wood pellets are increasingly being used to produce energy as a part of the decarbonization process of the economy, but their handling is associated with several problems, which usually requires that the equipment used has to be modified and improved. The discrete element method is a numerical technique suitable for simulating individual particles and handling systems. This paper focuses on the determination of the mechanical and physical parameters for wood pellet particles which are required to develop a discrete element method model to improve handling and transport systems. This study reports the experimentally determined values for wood pellet particles with respect to particle density, modulus of elasticity, particle – particle and particle – wall coefficients of restitution, and particle – particle and particle – wall coefficients of friction. Following the previous findings by other researchers with large samples of bulk material, it has been found that the modulus of elasticity for individual wood pellets depends on the water content, and the particle – wall coefficient of restitution depends on the impact velocity. K e y w o r d s: biomass, wood pellets, mechanical properties, discrete element method

Carbon consumption of developing fruit and the fruit bearing capacity of individual RoHo 3615 and Pinova apple trees

Abstract: photosynthetic capacity and derive the optimum fruit number for each individual tree, in order to achieve a defined fruit size, which is named as the fruit bearing capacity of the tree. The estimation of fruit bearing capacity was carried out considering the total leaf area per tree as measured with a 2-D LiDAR laser scanner, LALiDAR, and key carbon-related variables of the trees including leaf gas exchange, fruit growth and respiration, in two commercial apple orchards. The range between LALiDAR and LALiDAR was found to be 2.4 m2 on Pinova and 4.3 m2 on RoHo 3615 at fully developed canopy. The daily C requirement of the growing fruit and the associated leaf area demand, necessary to meet the average daily fruit C requirements showed seasonal variation, with maximum values in the middle of the growing period. The estimated fruit bearing capacity ranged from 33-95 fruit tree and 45-121 fruit tree on the trees of Pinova and RoHo 3615, respectively. This finding demonstrates sub-optimal crop load at harvest time in both orchards, above or below the fruit bearing capacity for individual trees. In conclusion, the LiDAR measurements of the leaf area combined with a carbon balance model allows for the estimation of fruit bearing capacity for individual trees for precise crop load management. K e y w o r d s: fruit growth rate, fruit respiration, leaf area, LiDAR, precision horticulture INTRODUCTION As a perennial plant, the production of premium size apples requires a balance of crop level and the ability of the tree to support the crop as well as flower bud development for the following year. Crop load management (CLM) targets the fruit number per tree to enable the growth to optimal fruit sizes by optimizing the carbon supply to demand balance for economically desirable fruit growth. Also, when performed less than 30 days after full bloom, CLM avoids a reduction in flower bud development to prevent alternate bearing on susceptible cultivars (Kofler et al., 2019). CLM may include pruning to reduce flower-bud numbers per branch (Breen et al., 2015), mechanical (Penzel et al., 2021) or chemical thinning of flowers (Janoudi and Flore, 2005) or fruitlets (Penzel and Kröling, 2020), and frequently corrective hand thinning after fruit drop. In order to optimize CLM for the quantity of profitable fruit size, it is crucial to define the optimum fruit number per tree, which should be considered as the target fruit number for the purposes of making an accurate determination of the intensity of each individual management practice (Treder, 2008; Robinson et al., 2017). The optimum fruit number per tree depends on the economically desirable fruit size at harvest, the daily C demand of growing fruit required to achieve this fruit size and the individual photosynthetic capacity of each tree to support fruit growth versus vegetative growth and flower bud development. ©2020Institute of Agrophysics, Polish Academy of Sciences M. PENZEL et al. 410 The photosynthetic capacity of fruit trees is associated with the extent of their generative and vegetative growth, both directly and indirectly determined by interacting factors of intra-plant competition. Furthermore, external factors such as light availability and interception, temperature, mineral nutrition, soil properties and water availability affect the photosynthetic capacity (Monteith, 1977; Xia et al., 2009; Lakso and Goffinet, 2017; Lopez et al., 2018). Physiological crop models can quantify cumulative effects of several factors on the magnitude of vegetative and generative growth of fruit trees (Lakso et al., 2001; Mirás-Avalos et al., 2011; Pallas et al., 2016). Therefore, physiological crop models are helpful in understanding the seasonal growth patterns of fruit trees or they may be used to determine the tree’s photosynthetic capacity and they can also be applied as a tool for decision support for precise orchard management (Lakso and Robinson, 2014). Furthermore, physiological and decision support models may be utilized to predict the optimum timing for the application of thinning agents (Robinson et al., 2017; Yoder et al., 2013), the thinning response (Greene et al., 2013), flower bud formation, fruit mass at harvest (Iwanami et al., 2018) and to estimate the target fruit number per tree (Handschack and Schmidt, 1990). In practice, the target fruit number per tree is, however, often estimated from the average yields of the previous years considering the mean of the entire orchard, divided by the number of trees in the orchard and the targeted fruit fresh mass. This approach leads to one level of treatment for all of the trees. This empirical method is not based on the natural variance in the capacity of each tree to support fruit of an economically desired size, namely the fruit bearing capacity (FBC), which can be highly variable within orchards (Manfrini et al., 2009). Therefore, the individual FBC of a certain number of trees is potentially over or underestimated by the established method. Overestimation of the FBC will lead to excessively high crop levels, poor fruit quality and reduced flower bud induction, while underestimation leads to too few fruits, a loss of crop value, reduced storability and an increased risk of storage disorders (Wójcik et al., 2001; Mussachi and Serra, 2018). As individual trees require a variable intensity of CLM, it is assumed that lack of treespecific CLM is an important cause of heterogeneity in fruit size, quality, and value. In order to observe the variability in the growth habits of trees, data from a large quantity of trees is required. Recent approaches used to detect flower clusters and the fruit of individual trees (Tsoulias et al., 2020) or to estimate other canopy parameters such as canopy height, volume or total leaf area, have shown promising results (Bresilla et al., 2019; Tsoulias et al., 2019; Hobart et al., 2020; Vanbrabant et al., 2020). When these techniques are implemented within existing physiological models, the data generated can potentially be applied to estimate the photosynthetic capacity of individual trees, the optimum and target fruit number per tree, their variability within an orchard, and the required variable intensity for precise CLM practice. The estimation of leaf area may be of outstanding importance, since the photosynthetic capacity of a tree relies on the total leaf area, especially from the exposed leaves, the quantity of light intercepted by the leaves and the photosynthetic conversion to fixed carbon. The percentage of leaf-assimilated carbohydrates partitioned to fruit, Cpart (%), is dynamic during the whole season, with significant changes in the first weeks after bloom (Hansen, 1967; Corelli-Grappadelli et al., 1994; Pallas et al., 2016). The magnitude of Cpart for a specific date is determined by the C supply to demand balance of the tree, which is influenced by the quantity and actual sink activity of all organs including shoots, fruit, leaves, branches, roots, and stem. Cpart can range from 0% on non-bearing trees to 85% on fruiting trees with a low leaf area to fruit ratio (LA:F) (Hansen, 1969; Palmer, 1992; Lakso, unpublished data). In periods showing C demand exceeding the supply in a particular apple tree, there is a prioritization in C partitioning among the sink organs, with the highest priority assigned to growing shoots (Bepete and Lakso, 1998). When shoot and leaf growth is complete, the highest priority for C partitioning is the fruit (Wagenmakers, 1996). When integrated over the whole season, Cpart is defined as the harvest index (HI). For fruiting trees of different cultivars, varying HI were reported in previous studies, ranging from 50% 85% (Koike et al., 1990; Palmer et al., 2002; Glenn, 2016; Lakso, unpublished data). They were typically grown on dwarfing rootstocks including M.9, M.26 and M.27. The HI is negatively correlated to the N supply of the tree, which positively affects the LA:F (Xia et al., 2009). The C supply to the individual fruit may limit fruit growth at different times during the season (Lakso and Goffinet, 2017) and, therefore, determine the fruit size at harvest time. Hence, assuming the total leaf area per tree is closely related to light interception, the fruit size at harvest is positively correlated to LA:F (Palmer, 1992) and can be further described as a hyperbolic function of the exposed LA:F of healthy LA, not affected by external stress. The effective LA required to produce a specific fruit size from a cultivar varies depending on the exposed versus shaded LA as demonstrated by earlier studies. Hansen (1969) reviewed several early studies concerning the relationship between LA:F and fruit size, pointing out that 300-500 cm2 LA:F, or 20-30 leaves per fruit, is the minimum requirement to achieve a marketable fruit size. The required LA:F in contemporary orchards may be different, because it may be assumed that at the time when the studies were carried out, the trees were probably not as optimally supplied with nutrients and water as in present day orchards. Other factors which affect the required LA:F are cultivar, rootstock, growing system and seasonal climate, all affecting the light interception of the trees and the HI. FRUIT BEARING CAPACITY IN APPLE 411 Previous studies have in common that the LA:F was determined at full canopy or at harvest. However, the fruit growth rate and related C consumption of individual fruit underlies seasonal changes (Schechter et al., 1993; Pavel and DeJong, 1995; Lakso and Robinson, 2014). As a consequence, since seasonal leaf area and fruit development occur with different patterns, it may be assumed that the LA:F required for fulfilling the fruit’s C requirement varies during fruit development. Additionally, the total LA per tree changes continuously during the season, as does the LA:F, until fruit drop and shoot growth have ended. Schumacher (1962) pointed out the negative effect of temporarily variable LA:F in or

Basic soil chemical properties after 15 years in a long-term tillage and crop rotation experiment

Abstract: Tillage systems are generally categorized in terms of conventional tillage using a mouldboard plough to turn over the soil, conservation tillage using a chisel plow, disk plow, harrow disk or cultivators, and no-till where seeds are sown directly into the untilled soil. In conventional tillage, all crop residues are incorporated while in conservation tillage or no-till these residues remain partly or completely on the soil surface. From a global perspective, the conventional tillage system is increasingly being superseded by the reduced tillage approaches. Whereas the plough is still dominant in Europe, conservation tillage and no-till are broadly applied in North and South America and in Australia (Derpsch et al., 2010). In a review of crop yields from several European countries, yields from no-till were within the 5% range of those obtained by mouldboard ploughing (Soane et al., 2012). Under Pannonian climate conditions on a Chernozem in Eastern Austria, winter wheat yields were generally at similar levels for conventional, conservation and no-till with no-till resulting in higher yields in very dry years and conventional and conservation tillage resulting in higher yields with higher amounts of rainfall during the vegetation period (Neugschwandtner et al., 2015a). Moitzi et al. (2019) reported for this experiment, that the direct energy input in no-till and shallow conservation tillage during crop cultivation was considerably lower than in mouldboard ploughing. © 2020 Institute of Agrophysics, Polish Academy of Sciences R.W. NEUGSCHWANDTNER et al. 134 This may result in an increase in the energy efficiency of these tillage systems, especially during dry years, when ploughless tillage systems tended to respond with competitive yields (Neugschwandtner et al., 2015a). The economic benefits of no-till include a reduction in fuel consumption and working time; both could be reduced by establishing wheat with no-till on a silty loam Chernozem as opposed to conventional establishment (i.e. using a heavy cultivator for stubble cultivation and a mouldboard plough and subsequent seeding, using a power harrow and a seeding machine) by about 85% (Moitzi et al., 2013; Szalay et al., 2015). The ecological benefits of no-till include an increase in biotic activity, especially earthworms, and of soil organic carbon, less soil erosion and lower carbon emissions (due to less fuel consumption) (Derpsch et al., 2010). Tillage operations alter nutrient dynamics on a shortterm scale through changes in the physical properties of the soil and the incorporation of crop residues and mineral or organic fertilizers. These effects accumulate in the longterm and an additional system effect builds up (Pekrun et al. 2003). Soil physical characteristics like soil aggregate stability, bulk density, pore volume and pore size distribution, infiltration and penetration resistance (Liebhard, 1993b; Liebhard, 1994; Liebhard et al., 1994; Liebhard et al., 1995) and soil chemical characteristics such as soil pH, soil organic matter and soil nutrients (Liebhard, 1993a; Neugschwandtner et al., 2014) are influenced by these long-term changes. The aim of this study was to assess the influence of four different soil tillage systems and two crop rotations on basic soil chemical parameters in soil layers fifteen years after establishing a static field trial on a Chernozem in eastern Austria. Several soil characteristics which were assessed in 2003, seven years after the start of the experiment, have been reported earlier by Neugschwandtner et al. (2014). MATERIALS AND METHODS The long-term experiment was carried out in Raasdorf (48° 14’ N, 16° 33’ E; altitude: 153 m a.s.l) in eastern Austria on the experimental farm of BOKU University. Raasdorf is located close to the east of Vienna, Austria, on the edge of the Marchfeld plain, an important crop production region in the north-western part of the Pannonian Basin. The silty loam soil is classified as a Chernozem of alluvial origin and is rich in calcareous sediments. The mean annual temperature is 10.7°C and the mean annual precipitation is 543 mm (1983-2012). The long-term experiment, which was established in 1996, is set up with a split-plot design using four replication blocks and involves two factors: the tillage system is assigned to the main plots (24 × 40 m) and crop rotation to the subplots (12 × 40 m). Fertilization is performed on a crop specific basis according to good agricultural practice, e.g. winter wheat was fertilized with calcium ammonium nitrate (27% N) at a rate of 130 kg N ha. The tillage variants include: (1) Mouldboard ploughing (MP) after harvest to a soil depth of 25-30 cm. The loosened soil is turned over and therefore residues are fully incorporated into the soil. (2) No-till (NT): Direct drilling in un-tilled soil with a disc drill without the previous removal of residues. A total herbicide (glyphosate) is applied before sowing for weed control. (3) Deep conservation tillage (CTd) to a soil depth of 20-25 cm is performed using a wing share cultivator and every four years a subsoiler is used to a depth of 35 cm. A part of the plant residues remain on the soil surface. (4) Shallow conservation tillage (CTs) to a soil depth of 8-10 cm using a wing share cultivator. A high share of the plant residues remain on the soil surface. Two flexible crop rotations are performed on subplots with sugar beet (rotation A; grown in four years) or maize (rotation B; grown in four years) as central crops. Both rotations frequently included winter wheat (in a total of seven years), as rotation effects on this crop shall be tested within this long-term experiment. Rotation A had a further two years of maize and in one year each, sunflower and spring durum wheat. Rotation B had a further two years of oilseed rape and one year each of sugar beet and soybean. Both rotations had in the four years (2008-2011) before sampling, the same crops but in a different time course: Rotation A – maize, winter wheat, sugar beet and winter wheat; Rotation B – winter wheat, maize, winter wheat and sugar beet. Crop residues were left on the field. Soil sampling was performed with soil probes (Purckhauer type, core diameter: 30 mm) in 5 cm steps at depths ranging from 0-30 and in 10 cm steps at depths ranging from 30-50 cm from the 7th to 9th of November, 2011. A mixed sample was composed per plot for each sampled layer consisting of 30 equally sized subsamples randomly collected from the individual plots. The samples were airdried, homogenized and sieved (2 mm). The crops grown before sampling were harvested in July (rotation A: winter wheat) and in October (rotation B: sugar beet). The soil pH was determined in a distilled water extract (pHH2O; 50 ml, w/v = 1:10) after 1 h of extraction and in a 0.01 mol l calcium chloride solution (pHCaCl2; CaCl2; w/v = 1:2.5) after 2 h of extraction (ÖNORM L 1083, 1999) using a Multi 3420 Multiparameter Meter (WTW GmbH, Weilheim, Germany). Electrical conductivity (EC) was measured simultaneously with pHH2O. The cation exchange capacity (CEC) was determined from the sum of Ca, Mg, K, Na and Al after extraction with 0.1 mol l BaCl2 (w/v = 1:10) for 2 h (ISO, 1994). Inductively coupled plasma-atomic emission spectrometry (ICP-OES) using an Agilent 720 (Agilent Technologies Inc., USA) was applied for element determination in the extracts. The total organic carbon (TOC) content was determined spectrophotometrically after the oxidation of organic matter by H2SO4 and K2Cr2O7 (Sims and Haby, 1971). The amount of total C and total N was determined from about 50 mg of soil by the SOIL CHEMICAL PROPERTIES AFTER 15 YEARS IN TILLAGE AND ROTATION EXPERIMENT 135 modified Dumas combustion method at 960°C with a CNS elemental analyser (vario MACRO cube CNS; Elementar Analysensysteme GmbH, Langenselbold, Germany). Statistical analyses were performed using software SAS version 9.2. An analysis of variance (PROC MIXED) was performed and the means were separated by the least significant differences (LSD), while the F-test indicated the factorial effects at the significance level of p < 0.05. Based on analysis of variance results, the data are presented as the main effects of depth or as tillage × depth interactions. As no significant differences were observed for crop rotation, means are indicated for each rotation (overall depths and tillage treatments). The Pearson correlation coefficient for analysed parameters was calculated for the depth of 0-5, 5-30, and 30-50 cm. RESULTS AND DISCUSSION The experimental site is characterized by a calcareous soil with an alkaline reaction. Values of pHCaCl2 were lower than those of pHH2O as soil extraction with CaCl2 causes a higher release of hydrogen ions into the solution compared to a soil extraction with H2O (Gavriloaiei, 2012). Both pHCaCl2 and pHH2O decreased with soil depth with pHCaCl2 (Fig. 1A) showing a more homogenous distribution up to a 25 cm depth while pHH2O gradually decreased with every sampled layer (except for similar values between a 10-15 and 15-20 cm depth). The vertical gradient of pHCaCl2 has already been reported for this experiment after seven years (Neugschwandtner et al., 2014). Similarly to pH, an increase in calcium carbonate (CaCO3) was found in this experiment seven years after its initiation (Neugschwandtner et al., 2014), as CaCO3 buffers the soil pH (Blume et al., 2019). There were no differences in pH between tillage treatments. This finding is consistent with those of other longterm tillage experiments; e.g. on a sandy loam soil in the Northern Great Plains after 12 years (Aase and Pikul, 1995), under temperate conditions on a Luvisol in France after 32 years (Limousin and Tessier, 2007), and in a semiarid, subtropical environment on a Luvisol in Australia after 9 years (Thomas et al., 2007). A higher acidity with no-till in the upper soil layers was reported from other studies which attributed this effect to acidification proce

Suitable model for thin-layer drying of root vegetables and onion

Abstract: *Corresponding author e-mail: krzysztof_gornicki@sggw.pl A b s t r a c t. The drying behaviour of carrot, parsley, red beetroot and onion slices of 5 and 10 mm thickness was investigated in a convective dryer at a drying temperature of 50, 60 and 70°C under natural convection conditions. The experimental drying data of the vegetables slices obtained were fitted to five empirical thin-layer models: Lewis (Newton), Henderson and Pabis, Page, Modified Page, Wang and Singh. The effects of the vegetable species, air drying temperature, and slice thickness on the model parameters were determined. Four statistical tools, namely, the determination coefficient, root mean square error, reduced chi-square, and t-statistic method were applied to determine the fittings. The Page model with the model parameters determined by a summation equation, a square type dependence for the drying air temperature and a rational one for the slice thickness is recommended as the most suitable model (R = 0.9699, RMSE = 0.0587, χ = 0.0035, t-stat = 0.6739). K e y w o r d s: root vegetables, onion, drying kinetics, modelling, drying models

Landsat and Sentinel-2 images as a tool for the effective estimation of winterand spring cultivar growth and yield prediction in the Czech Republic

Abstract: *Corresponding author e-mail: jelinekzdenek@tf.czu.cz **This work was supported by Internal Grant Agency of the Faculty of Engineering, CZU Prague, internal grant number 31180/1312/3118. The support from project MZE-RO418 is also acknowledged (2018-2022). A b s t r a c t. The influence of climate and topography on crop condition and yield estimates is most effectively monitored by non-invasive satellite imagery. This paper evaluates the efficiency of free-access Sentinel 2 and Landsat 5, 7 and 8 satellite images scanned by different sensors on wheat growth and yield prediction. Five winter and spring wheat cultivars were grown between 2005 and 2017 in a relatively small 11.5 ha field with a 6% slope. The normalized difference vegetation index was derived from the satellite images acquired for later growth phases of the wheat crops (Biologische Bundesanstalt, Bundessorenamt and Chemical industry 55 – 70) and then compared with the topography wetness index, crop yields and yield frequency maps. The results showed a better correlation of data obtained over one day (R = 0.876) than data with a one-day delay (R = 0.689) using the Sentinel 2 B8 band instead of the B8A band for the near-infrared part of electromagnetic spectrum in the normalized difference vegetation index calculation. K e y w o r d s: satellite sensors, agriculture, satellite imagery, wheat varieties

Effects of supplemental lighting during the period of rapid fruit development on the growth, yield, and energy use efficiency in strawberry plant production

Abstract: Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka, 819-0395, Japan Faculty of Agriculture, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan Kyushu Okinawa Agricultural Research Centre, National Agriculture and Food Research Organization, 1823-1 Miimachi, Kurume, Fukuoka 839-0851, Japan Faculty of Agriculture, University of Sultan Ageng Tirtayasa, Jl. Raya Jakarta km.04, Serang, 42124, Indonesia Indonesia Centre of Excellence for Food Security, University of Sultan Ageng Tirtayasa, Jl. Raya Jakarta km.04, Serang, 42124, Indonesia National Institutes for Quantum and Radiological Science and Technology, 1233 Watanukimachi, Takasaki, Gunma 370-1292, Japan

Physical stability of model emulsions based on ethyl cellulose oleogels

Abstract: *Corresponding author e-mail: iwona_szymanska@sggw.edu.pl A b s t r a c t. The purpose of this study was the evaluation of the physical stability of low-fat oil-in-water model emulsions containing oleogels based on ethyl cellulose), compared to emulsions with anhydrous milk fat. The oleogels were prepared using rapeseed oil with ethyl cellulose at the level of 4.5, 5.0, 5.5 or 6.0% w/w. The O/W emulsions (30/70 w/w) were stabilized by guar gum (0.6% w/w) and soy lecithin (5.0% w/w). The physical properties of oleogels and anhydrous milk fat (centrifugal stability, spreadability/penetration test), rheology and the physical stability of the emulsions (MS-DWS method, centrifugal/thermal stability) were determined, a storage test of the emulsions (CSA method, LUMiSizer) was also conducted. It was demonstrated that ethyl cellulose is an effective edible oil structuring agent. The increase in ethyl cellulose content enhanced the centrifugal stability and hardness of the oleogels. As a result of a microrheology analysis, it was found that the emulsion with anhydrous milk fat had the most elastic strength, macroscopic viscosity and the highest solids content. All emulsions demonstrated high centrifugal/ thermal stability. A higher temperature and extended storage time caused a reduction in the stability of all emulsions and increased the velocity of particle migrations. The ethyl cellulose-oleogels are potential fat phases for stable O/W emulsions, which could be used as a vegan alternative to traditional products based on animal components. K e y w o r d s: oleogels, ethyl cellulose, oil-in-water emulsions, MS-DWS method, storage test, CSA method

Quantification of the relationship between root parameters and soil macropore parameters under different land use systems in Retisol

Abstract: *Corresponding author e-mail: mykola.kochiieru@lammc.lt A b s t r a c t. The study aimed to quantify the relationship between root parameters and soil macropore characteristics in two soil layers of Retisol from a hilly landscape in Western Lithuania, as influenced by different land use systems. The decreases in root volume and root length density were dependent on land use and soil depth. The values of root length density and root volume at 0-20 cm depth tended to decrease in the following order: grassland > forest > arable land under conventional tillage. The highest volume in the framework of macropores was recorded for medium-size pores under arable land (3.02%), for fine pores (2.56%) in forest soil and very fine pores in grassland soil (below 1.19%) at the 0-10 cm soil depth, while at 10-20 cm soil depth, the coarse macropores dominated in the arable land system (below 1.41%). Root length density, root volume and the volume of very fine macropores had close relationships (p < 0.01, r = 0.91 and r = 0.68, respectively) under different land use at 0-20 cm depth. In Retisol, the roots were concentrated at 0-10 cm soil depth, and their volume was higher compared to the 10-20 cm depth. Plant roots increased the volume of very fine macropores in all land use systems, within the entire 0-20 cm soil depth. K e y w o r d s: plough layer, porosity, root length, root volume, tillage, X-ray computed tomography

Response of dry matter translocation and grain yield of summer maize to biodegradable film in the North China Plain

Abstract: *Corresponding author e-mail: quanqili@sdau.edu.cn **This work was supported in part by the National Key Research and Development Plan (2016YFB0302402) (20162021), and by the Funds of Shandong “Double Tops” Program (SYL2017YSTD02), (2017-2020). A b s t r a c t . In the North China Plain, it is a matter of urgency to explore the feasibility of using biodegradable film to replace polyethylene film. A field experiment was conducted by covering soils with polyethylene white film, biodegradable white film, biodegradable black film, while the control remained uncovered. This study analysed the effects of using different film types on summer maize dry matter accumulation and transfer, grain yield and yield components during the 2016 and 2017 summer maize growing seasons. Results showed that, for both growing seasons, compared with non-mulching, dry matter translocation, dry matter transfer efficiency of vegetative organs and grain yield for plants following polyethylene white film and biodegradable white film treatments were always lower. However, dry matter accumulation, dry matter translocation, dry matter transfer efficiency, grain yield, and the contribution of dry matter translocation to grain yield before flowering in biodegradable black film treatments significantly increased by 21.0, 33.3, 21.4, 12.6, and 18.5%, respectively. Only the black biodegradable film could increase grain yield as determined by the 1000 kernel mass. Results indicate that black biodegradable films are a viable alternative to polyethylene film in summer maize production in the North China Plain. K e y w o r d s: polyethylene film, leaf area index, dry matter transfer, yield components, North China Plain

New biochars from raspberry and potato stems absorb more methane than wood offcuts and sunflower husk biochars

Abstract: *Corresponding author e-mail: a.kubaczynski@ipan.lublin.pl **This work was partially conducted as a part of the project “Water in soil satellite monitoring and improving the retention using biochar” no. BIOSTRATEG3/345940/7/NCBR/2017 which was financed by Polish National Centre for Research and Development within the framework of “Environment, agriculture and forestry” BIOSTRATEG strategic R&D programme (2018-2020). A b s t r a c t. The reduction in greenhouse gas emissions from agriculture is of particular importance at present. In recent times, biochar addition to the soil was suggested as a means of mitigating greenhouse gases emissions from arable fields. More specifically, biochars with useful properties and those produced from easily available waste materials are still being sought. In the presented experiment, the CH4 absorption potential of four biochars incubated at 60 and 100% water holding capacity with the addition of 1% CH4 (v/v) was investigated for 28 days at 25C. The potato stem and raspberry stem biochars showed much higher potentials for CH4 uptake than wood offcuts biochar and sunflower husk biochar. Potato stem and raspberry stem biochars incubated at 60% water holding capacity were characterized by a methane uptake rate of 8.01 ± 0.47 and 5.78 ± 0.17 mg CH4-C kg d, respectively. The methane removal potentials of the other biochars were clearly lower. The advantage of the biochars from raspberry and potato stems over the wood offcuts biochar also results from their significantly lower production of carbon dioxide. Consequently, these materials have a high potential for agricultural use, in view of their impact on the greenhouse gas balance of the soil. K e y w o r d s: biochar, methane, greenhouse gas removal, raspberry stems, potato stems

Tests and analyses on mechanical characteristics of dwarf-dense-early major cotton variety stalks

Abstract: tors, mechanical characteristics

Influence of substrate type and properties on root electrical capacitance

Abstract: effective application of the root capacitance technique. K e y w o r d s: root electrical capacitance, root-soil system, soil salinity, soil water content, two-dielectric capacitor model

Thermal conductivity of a Brown Earth soil as affected by biochars derived at different temperatures: Experiment and prediction with the Campbell model

Abstract: *Corresponding author e-mail: zhbw2001@sina.com **This research was financially supported by the National Natural Science Foundation of China (51766008 (2018-2021), 21467013 (2015-2018), and 21167007 (2012-2015)). A b s t r a c t. Thermal conductivity is a significant heat transfer property of soil. However, the influence of biochar on this property is not well known. In this research, the influence of corn straw biochars prepared at 300, 500 and 700C on the thermal conductivity of a Brown Earth (Hapli-Udic Cambisol, FAO) soil and its prediction using a Campbell model was examined. The outcomes revealed that the bulk densities of the soil markedly decreased with increases in the biochar amendment rates of 1, 3, and 5% in linear patterns. The reduction in bulk density was mainly attributed to an increase in soil porosity and organic carbon content. With increasing volumetric water contents (10, 20, 30 and 40%), the thermal conductivity of the soils significantly increased, whereas those of soils with biochar amendment were obviously less than that of the CK and the differences increased with the biochar application rates. The pyrolysis temperature of biochar exhibited a negligible effect on the bulk density and thermal conductivity of soils at large. Combining the linear reduction of bulk density with the biochar amendment rate into the Campbell model, well-fitting results for the variation inthermal conductivity versus volumetric water content were obtained and accurate values could be predicted. K e y w o r d s: biochar, bulk density, thermal conductivity, Brown Earth soil, Campbell model

Impact of marble powder amendment on hydraulic properties of a sandy soil

Abstract: This work was partially funded by the project GRE17-12 from the University of Alicante (2018-2019).

Electrical resistivity tomography for spatiotemporal variations of soil moisture in a precision irrigation experiment

Abstract: *Corresponding author e-mail: mertzan@gmail.com **The research leading to these results has received funding from the European Community’s Seventh Framework Program (FP7/2007-2013) under grant agreement 311903 – FIGARO (Flexible and Precise Irrigation Platform to Improve Farm-Scale Water Productivity (http://www.figaro-irrigation.net/). A b s t r a c t. Soil moisture temporal variations play a key role in the hydrological processes occurring in the unsaturated zone, which are critical for annual crop yields. The electrical resistivity tomography technique was applied in a field cultivated with cotton in northern Greece, thereby investigating its potential to serve as a reliable soil moisture-monitoring tool for precision irrigation in highly heterogeneous, clay-rich soils. Repeated surface resistivity measurements were made along two plant lines combined with soil water content measurements conducted with a reference gravimetric method and an electromagnetic sensor. Resistivity pseudo-sections were inverted to produce 2D resistivity models, and time-lapse inversion algorithms were also used, to better calculate the temporal changes in subsurface soil resistivity. The results showed clear spatial and temporal changes in resistivity transects in accordance with rainfall/irrigation and dry periods. The soil resistivity data exhibited a power model relationship with gravimetric soil moisture point measurements and a fair correlation with electromagnetic sensor profiles. K e y w o r d s: electrical resistivity tomography, non-intrusive soil measurements, soil moisture determination; heterogeneous clay-rich soils, water-saving technology

Dynamics of slope processes under changing land use conditions in young morainic landscapes, Western Lithuania

Abstract: *Corresponding author e-mail: swit@umk.pl **This work was conducted under the long-term research program “Productivity and sustainability of agricultural and forest soils” implemented by the Lithuanian Research Centre for Agriculture and Forestry (2010-2018). A b s t r a c t. The long-term field study (1995-2012) concerning soil erosion was conducted on an experimental slope-plot situated on a moraine hilly agricultural landscape of the southerncentral Zemaiciai Uplands, Lithuania. The aim of the presented studies is to determine changes in the volume of soil loss under typical field crop rotation conditions with bare fallow and to estimate the impact of erosion on soil properties. Surface runoff and soil loss rates were measured on a bounded runoff plot draining to a collector tank that trapped both sediments and water. Changes in precipitation, rain intensity and land use substantially affected the rate of the erosion processes. It was found through a comparison of three-crop rotation periods that the highest intensity of slope soil transfer occurred during the time period of 2007-2012 (3rd crop rotation) due to extreme rainfall events. Developing the dynamics of vegetation cover to prevent soil erosion phenomena showed a significant difference in plant growth conditions and the suitability of various plants for soil protection. The lowest ratio of soil loss was measured on a hillslope covered by perennial grasses. The years characterized by the highest erosion rates were associated with bare fallow land use when soil losses were even 470 times higher than under perennial grasses. K e y w o r d s: soil erosion, surface runoff, young glacial landscapes, colluvial soils, crop rotation

Seed yield and physiological responses to deal with drought stress and late sowing date for promising lines of rapeseed ( Brassica napus L.)

Abstract: Due to the rainfall deficit in various regions of the world, which has caused drought, releasing the varieties/ lines of plants which are resistant to drought stress has a particular importance in the regions of the world with low levels of precipitation. The rapeseed (Brassica napus L.) crop contains 40-44% oil and is considered to be one of the most important edible oilseeds (Ashkiani et al., 2020; Cashin et al., 2014; FAO, 2018), being the third annual oil crop in the world after soybean and oil palm (Enjalbert et al., 2013). One of the most critical factors that inhibits the development of the area under cultivation and prevents the successful production of rapeseed in semi-arid regions is moisture deficiency at the end of the growth period (reproductive stage) to which it is very susceptible (Nasiri et al., 2017). Among the various abiotic stresses, drought stress is the most severe, destructive and significant restricting environmental factor for sustainable agricultural production (Ardakani et al., 2009; Davaran Hagh et al., 2016; Pace and Benincasa, 2010;Yuncai and Schmidhalter, 2005). © 2020 Institute of Agrophysics, Polish Academy of Sciences M. TEYMOORI et al. 322 Hammac et al. (2017) assessed the effect of drought stress on seed yield, as well as the protein and fatty acids content of the rapeseed and reported that drought stress at the flowering stage had significant effects on unsaturated fatty acids, protein, and seed yield. Photosynthesis limitation through metabolic destruction is a complicated phenomenon, in which pigments have a protective task (Jaleel et al., 2009; Khan et al. 2010). Chlorophyll loss under drought stress causes damages due to the formation of free oxygen radicals (Gaspar et al., 2002; Hoseinzade et al., 2016; Ilkaei et al., 2011). Drought stress mediated by soil moisture deficiency in flowering and silique development stages decreased chlorophyll a and b contents in various rapeseed lines compared with the irrigation treatment (Din et al., 2011; Grewal, 2010; Saranga et al., 2001). Due to the water deficiency problem in arid and semiarid regions across the globe such as Iran, the feasibility of late rapeseed and the simultaneous cultivation of the crop with spring crops may be considered as a management strategy for the optimal use of irrigation water. Additionally, the irrigation of rapeseed at the late growth season coincides with the first irrigations of spring crops after rapeseed. It is also very important to select superior promising lines that can potentially respond well to delayed cultivation and water deficiency problems, which was the aim of this study. MATERIALS AND METHODS This experiment was conducted in the research farm of the Seed and Plant Improvement Institute (Karaj, Iran) during 2015-2017. The geographic coordinates of the experimental farm were 35 ̊49’ N and 51 ̊6’ E, with an altitude of 1321 m above sea level. This region has a warm and dry Mediterranean climate zone, as well as a dry moisture regime due to the cold and humid winters and warm and dry summers, there are from 150 up to 180 dry days per year based on meteorological information. The average regional yearly precipitation is 243 mm. Rainfall occurs mainly late in the fall and early in spring. The average maximum annual temperature is 28 ̊C in July, and an average minimum temperature of 1 ̊C occurs in January. The average 30-year soil temperature is 14.5 ̊C. The amberothermic graph for the two years of the experiment is illustrated in Fig. 1. The soil was sampled before fertilization from a depth of 0-30 cm. The soil had the following characteristics: organic carbon (0.64%), electrical conductivity (EC) of 1.70 ds m, soil nitrogen (0.06%), and absorbable phosphorus and potassium (10.3 and 275 mg kg of soil, respectively). The soil texture was clay loam (sand 28.80%, clay 41.88%, and silt 29.32%). A factorial split-plot experiment was conducted in a completely randomized design with three replications over two years (2015-2017). The sowing dates were October 12 (conventional date) and November 1 (late sowing) with irrigation as the variable in the main plots, this took place at two levels: normal irrigation (control) and discontinuing irrigation from the silique forming stage (development of fruit stage, BBCH: 71) to the next stage (late-season drought stress). The subplots included promising new lines of open-pollinated rapeseed, that were L1112, L1091, L1093, L1206, which were originally released in Iran according to the national breeding programs for oilseeds crops and an open-pollinated cultivar, Okapi (French origin) as a control to be compared with the new lines. Each plot included six rows, with a length of 6 m, a distance of 30 cm between the lines, and a plant distance of 4 cm on the lines. The two outer rows were considered to be the border, and the four inner lines were used to evaluate various plant traits. During both cropping years, fertilization was carried out by using nitrogen (urea 150 kg ha, one third was applied at sowing time, one third at the stem elongation stage and one third at the beginning of the flowering stage), phosphorus (100 kg ha Triple-Superphosphate at sowing time) and potassium (50 kg ha Potassium Sulphate at sowing time). Fig. 1. Climatology curve (amberotermic graph) for Karaj province from October 2015 to July 2017. LATE SOWING DATE OF RAPESEED LINES 323 Treflan herbicide was evenly sprayed at a volume of 2.5 l ha.The fertilizers and herbicide were incorporated into the soil with a light disc. Pests, in particular the mealy aphid, were controlled through the application of Metasystox pesticide (1.5 l ha). Irrigation was implemented using siphon pipes based on 80 mm evaporation from the surface of a Class A evaporation basin and water deficiency stress treatments consisted of eight common irrigation steps, of which only six steps were carried out and irrigation cessation took place from the silique formation stage to the next stage and the amount of water used in these treatments was 5 120 and 3 840 m ha, respectively (with due consideration of precipitation during the growth period for both years). Ten plants were randomly selected from each experimental plot to determine the plant traits. The relevant physiological traits were evaluated through the random selection of the youngest developed leaves of the third internode from the top of the plant per experimental plots during the fruit development stage (BBCH: 75). In order to measure the leaf relative water content (LRWC) 10 leaf samples were randomly selected from each experimental plot and this parameter was calculated according to Ferrat and Loval (1999) using Eq. (1):

Effect of extrusion-cooking conditions on the physical properties of Jerusalem artichoke straw

Abstract: *Corresponding authors e-mail: tomasz.oniszczuk@up.lublin.pl agnieszka.wojtowicz@up.lublin.pl maciej.combrzynski@up.lublin.pl A b s t r a c t. The paper presents the effect of extrusion-cooking conditions (moisture content and screw speed) on the physical properties of extruded Jerusalem artichoke straw. A single screw extruder was used for straw processing. Shredded Jerusalem artichoke straw moistened to 30, 40, and 50% was subjected to an extrusion-cooking process at various screw speeds (70, 90, and 110 rpm). Selected physical properties and pasting profile were tested. Significant differences were observed depending on the moisture content of the samples and the various screw speed on their physical properties. Notably, increased moisture content lowered the specific mechanical energy, increased processing efficiency, water solubility, peak viscosity and breakdown. The maximum efficiency and the highest breakdown was observed for the sample with 50% moisture content processed at an extruder screw speed of 90 rpm. The sample obtained at 30% moisture and at 90 rpm was characterized by the lowest efficiency and hot paste viscosity, and the highest specific mechanical energy. The results showed that the extrusion-cooking process yielded desirable changes to the structure of the analysed lignocellulosic biomass. K e y w o r d s : pretreatment, lignocellulosic biomass, physical properties, extrusion-cooking, Jerusalem artichoke straw

Analysis of morpho-anatomical stem properties determining its mechanical strength in selected rye cultivars

Abstract: *Corresponding author e-mail: tomasz.wojtowicz@urk.edu.pl **This work was financed by the Ministry of Science and Higher Education of the Republic of Poland (2017-2019). A b s t r a c t. The objective of the research was to compare important properties of the morphological and anatomical structure of stems of four open-pollinated rye cultivars in relation to their mechanical strength expressed by the failure moment, taking into account the possibility of using the stems for the manufacture of natural drinking straws. From the 2nd and the 3rd stem internodes, cross sections were obtained within which the number of large vascular bundles, the diameters of the stem and the central canal, as well as the thicknesses of the stem wall, sclerenchyma and parenchyma were determined. The differentiation in cultivar properties was mainly affected by the location of the internode within the stem. The stem diameter ranged from 5.2 mm (Dańkowskie Rubin) to 5.4 mm (Antonińskie). As compared with the 3rd internode, in the 2nd internode the values of the analysed traits ranged from 5 to 25% higher. In both internodes a significant correlation (r>0.680, p<0.01) between the stem diameter and the central canal diameter was found. In all the cultivars the failure moment depended significantly on the stem diameter for both the internodes (r > 0.638, p < 0.01). The analyses carried out show that the 2nd internode is characterized by the most favourable properties affecting the mechanical strength of rye stems. K e y w o r d s: Secale cereale, biodegradable straws, mechanical properties, failure moment (Bs), stem anatomy

Comparison of commonly used extraction methods for ergosterol in soil samples

Abstract: sequestration, various methods have been used to extract ergosterol from soil samples. This study aims to explore the extraction ability and applicability of commonly used methods to extract ergosterol from two contrasting soils. An agricultural soil (chernozem) and a forest soil (podzol) were extracted with different types of cell lysis such as alkaline, glass bead, and ultrasonication methods in association with simple shaking. The ergosterol concentration was measured by high pressure liquid chromatography. Regardless of the method applied, ergosterol yield was higher in podzol than in chernozem. Alkaline extraction resulted in the highest ergosterol concentrations for both soils and miniaturized glass bead extraction produced comparable results in the case of chernozem. In terms of applicability, the non-alkaline methods were simpler to conduct and less demanding of labour, chemical use and glassware and more flexible in terms of the equipment used for mechanical disruption. Despite the limit of the two soil types in the present study, only the simple shaking method was revealed to be dependent on soil type. Based on our results, we recommend the miniaturized glass bead method for agricultural soils, low in organic matter for high throughput. However, not all of the methods described allow for the proper separation of coextracted organic substances from organic-rich soil. K e y w o r d s: soil, alkaline extraction, ergosterol extraction, glass bead beating, ultrasonication extraction INTRODUCTION Ergosterol, (22E)-Ergosta-5,7,22-trien-3β-ol (C28H44O), is a lipid found in the cell membranes of most fungi and some microalgae (Wallander et al., 2013). It is widely used as a biomarker to estimate fungal biomass in soil. Hence, the quantity of ergosterol in soil can refer to the contribution of fungi to soil organic matter content and subsequently soil organic carbon. However, this data requires careful consideration due to the turnover period of ergosterol in soil after cell death (Young et al., 2006; Zhao et al., 2005) and the lack of ergosterol in the cell membranes of e.g. arbuscular mycorrhiza (van Groenigen et al., 2010) and some Zygomycota (Strickland and Rousk, 2010). Due to the complexity of organic substances in soil and the composition of the fungal cell membrane, the extraction of ergosterol from soil samples is a crucial step for the determination of its amount in the soil. Various methods are known to successfully extract ergosterol from soil samples followed by quantification using high-pressure liquid chromatography (HPLC) or gas chromatography (GC) (Beni et al., 2014; Joergensen and Wichern, 2008). Soil scientists are attempting to improve © 2020 Institute of Agrophysics, Polish Academy of Sciences Note O. SAE-TUN et al. 426 the extraction methods to save money and time and reduce the use of hazardous chemicals by applying physical disruption and omitting or accelerating the saponification step. Together with the cell physical disruption, pure ethanol, pure methanol or a methanol-ethanol mixture are used to extract ergosterol from the soil samples without the use of an alkaline solution (Feeney et al., 2006; Joergensen and Wichern, 2008). Some options for physical disruption such as bead-beating, shaking and ultrasonication with less use of hazardous chemicals produce the advantageous characteristics of non-alkaline extractions over alkaline extractions. Apart from that, the process of non-alkaline extraction is also simple due to the omission of the saponification step as well as liquid-liquid phase separation. Therefore, nonalkaline extraction can only extract free ergosterol unlike alkaline extraction (Eash et al., 1996; Seitz et al., 1977). The use of alkaline solution e.g. methanolic potassium hydroxide (KOH) for saponification targets the liberated esterified ergosterol from fungal cells. Homogenization by ultrasonication and saponification under heating conditions can accelerate the alkaline extraction process (Bååth and Anderson, 2003). After saponification, further steps, including phase separation, purification and derivatization are implemented before quantification by HPLC or GC (Joergensen and Wichern, 2008; Turgay and Nonaka, 2002). Although non-alkaline extractions cannot liberate esterified ergosterol, ergosterol yields from both non-alkaline and alkaline methods may be comparable (Joergensen and Wichern, 2008). No final explanation has been reached to explain those findings due to the present limits of knowledge concerning the nature of ergosterol in soil fungi (Ruzicka et al., 2000). It has been suggested that saponification during alkaline extraction could possibly result in the decay of some pre-existing free ergosterol (Djajakirana et al., 1996). When exposed to ultraviolet (UV)-light, the photochemical reaction of ergosterol causes pro-vitamin D creation; however, low energy laboratory light conditions are not sufficient to trigger this reaction (Newell et al., 1988). The stability of the extracted ergosterol could be preserved by storing it in the dark at 4°C for up to 3 days prior to quantitative determination (Beni et al., 2014). In ecological studies the heating effect on ergosterol yield and stability from complex samples such as soil is poorly understood. Verma et al. (2002) suggested an optimal heating period at 85°C for 30 min could enhance both the opening of the fungal cell and the release of esterified ergosterol bound to other solid substances during saponification; however, longer heating periods could potentially break down the ergosterol. The purpose of this study was to implement and compare commonly used extraction methods for the fungal biomarker, ergosterol, from two different soils. Four methods for cell lysis were explored in detail: (i) alkaline extraction, (ii) glass bead, (iii) ultrasonication, and (iv) simple shaking methods. All of the methods were used to extract ergosterol from distinct soils comprising agricultural and forest soils to determine their extraction yields and applicability. We expect that all of the methods used will show a higher fungal content in the forest soil than in the agricultural soil with their consistent extraction ability. In addition to ergosterol yield, it is proposed that the co-extraction of organic compounds is more critical for forest soil where organic matter is rich. This may result in more pronounced differences of applicability among the methods. MATERIALS AND METHODS Topsoils (0 – 10 cm depth) from forest and agricultural lands were studied. An acidic podzol with a silty loam texture was collected from a spruce-fir forest in the Wienerwald, Dürrwien, Austria. An alkaline chernozem with a sandy loam texture was sampled from the Marchfeld in Lower Austria. More details concerning the study site of the chernozem were described in Schomakers et al. (2015). The podzol, as a forest soil, was rich in organic matter of 21.4% (Table 1) while the agricultural chernozem had a low organic content of 1.17%. Prior to extraction, the soil samples were sieved with a 2 mm size sieve and air-dried. Due to the extensive use of the alkaline extraction method in soil study (Beni et al., 2014; de Ridder-Duine et al., 2006), it was selected as a reference method in our study. The alkaline extraction method used in our study followed the procedure from Bååth (2001) with a soil:solvent ratio of 1:5 (weight to volume ratio, w/v). Details concerning the extraction are provided in Appendix A. The method of ergosterol extraction with glass beads was modified from Gong et al. (2001). The procedure was conducted using two different scales (normal and miniaturized), while the soil:solvent ratio was maintained at 1:5 (w/v). Soil samples of two different weights, 2 and 0.16 g were extracted with methanol (MeOH) for the normal-scale and miniaturized extractions, respectively. The details of the extractions are included in Appendix A. The utrasonication method utilized power from ultrasonic waves to physically disrupt fungal cells in non-alkaline solvent (Ruzicka et al., 1995). A soil sample of 2 g was Ta b l e 1. Soil characteristics of chernozem and podzol Soil Chernozem Podzol Land use Agricultural land Spruce-fir forest Soil texture Silty loam Sandy clay-loam

Stress equation for a cantilever beam: a model of lodging resistance in field pea

Abstract: Department of Crop and Soil Sciences, Washington State University, PO Box 646420, Pullman, WA, USA 99164-6420 Department of Plant Sciences & Plant Pathology, Montana State University, PO Box 173150 Bozeman, MT, USA 59717-3150 Civil and Environmental Engineering, Washington State University, PO Box 642910, Pullman, WA 99164 Plant Sciences, Crop Development Centre, University of Saskatchewan, 2C04-Agriculture Building, Saskatoon, SK, Canada S7N 5A8

Impact of chemical and physical properties on flowability characteristics of corn distillers dried grains with solubles

Abstract: The rapid expansion of commercial ethanol production, esp. in the United States, has resulted in a significant increase in the availability of corn distillers dried grains with solubles (DDGS), a co-product of the ethanol production process (De Matteis et al., 2019). Total annual ethanol and DDGS production in the USA is 15 billion gallons and 44 million metric tons, respectively, making the USA the world’s largest DDGS producer (US Grains Council, 2019). As DDGS production increases in the USA, larger amounts are being exported to foreign countries, with the top four destinations being Mexico, South Korea, Turkey, and Vietnam (US Grains Council, 2019). Due to the usage of nearly all of the starch in the grain by yeast during fermentation, the proportion of most of the other nutrients such as protein, fat, and fibre, etc. in DDGS increases up to 2or 3-fold compared to the grain itself (Bandegan et al., 2009). As a consequence, the addition of DDGS to animal diets has become a very common practice due to the high energy, mid-range protein, and high digestible phosphorus content (Świątkiewicz and Koreleski, 2008; Kingsly et al., 2010). However, a downside of DDGS is its poor flow characteristics especially in storage and transport vessels, this factor can have a direct negative impact on its marketability (Kingsly et al., 2010). The flowability of feed mixtures is an important aspect of the © 2020 Institute of Agrophysics, Polish Academy of Sciences A. Y. PEKEL et al. 196 feed handling characteristics that affect both feed manufacturing and farm feed operations such as storage in silos and feeding systems (Ganesan et al., 2008). Flowability can be defined as the ability of a powder to flow in the desired manner in a specific piece of equipment. Therefore, it depends on both the feed characteristics which are mainly physical properties and the equipment and container used for handling, storing or processing the feed material (Juliano and BarbosaCanovas, 2010). The bulk density (BD), moisture content, particle size, particle shape, permeability, and conductivity are some of the physical properties that have been identified as having an impact on feed flow characteristics (Bhadra et al., 2008; Crawford et al., 2016). Moreover, the flowability of feedstuffs can also be significantly influenced by their chemical composition, such as ether extract (EE) and crude protein contents (CP) (Bhadra et al., 2008). The angle of repose (AR) is often used as an indication of the flow characteristics of powders including feeds. The AR is the maximum angle of a pile to the horizontal surface at which the material can remain in place without sliding or slumping (Zou and Brusewitz, 2002). Bhadra et al. (2009) reported that commercial DDGS samples had the potential for flow problems in the field. Moreover, the flow of DDGS has been reportedly impaired by caking and bridging during its storage and transportation (Ganesan et al., 2008). Since DDGS is a hygroscopic product, under appropriate conditions such as long distance shipping in a high humidity environment the formation of caking may occur (Saragoni et al. 2007). In particular, the chemical composition has been found to influence the water sorption of DDGS, which suggests the possible role of nutrients in the caking process (Kingsly and Ileleji, 2009). However, information concerning the chemical features affecting the flow characteristics of DDGS is scarce. In addition, BD of DDGS has been identified as having a key effect on flowability (Keirleber and Rosentrater, 2010). Therefore, it was hypothesized that BD, compressibility, and the nutrient composition of DDGS are some of the features that might affect its flowability through AR. The aim of the current study was to determine the significant physical and chemical properties that influence the flow characteristics of DDGS which can be used to estimate its flowability. MATERIALS AND METHODS The DDGS samples (n = 18) used in the current study were gathered from different feed mills between March and December 2017. Special attention was paid to collecting samples with colour characteristics ranging from light yellow to dark yellow in visual appearance in so far as this was possible (b* values were from 28 to 36) to improve the degree of variety and cover a wide range of samples with different colour features. Approximately 1 kg of each sample was sealed in plastic bags and stored at 4°C until analysis. Samples of DDGS were ground to a sufficiently fine consistency to pass through a 0.5 mm screen using an ultracentrifugal rotor mill grinder (Retsch ZM 200, Retsch GmbH Co. KG, Haan, Germany). The dry matter (DM), crude ash, EE, CP, P, crude fibre, acid detergent fibre (ADF), and neutral detergent fibre (NDF) were determined in triplicate. The DM content of the samples was determined by drying the samples at 105°C for 18 h in an oven (method 930.15; AOAC, 2006). The crude ash content of the DDGS samples was determined by ashing in a muffle furnace overnight at 600°C (method 942.05; AOAC, 2006). The ether extract content of the samples was determined with the use of a gravimetric extraction procedure using petroleum benzene in a Soxhlet apparatus for approximately 2 hours and 15 minutes (method 984.13; AOAC, 2006). The nitrogen content was determined with a Kjeltec analyser (method 984.13; AOAC, 2006) using the Kjeldahl method. In brief, the samples were digested in a digester (Gerhardt Kjeldatherm KB, Bonn, Germany) using sulphuric acid and then the resulting ammonium sulphate was distilled using NaOH in a distillation unit (Gerhardt Vapodest 50 Carousel, Germany). The crude protein values were derived from multiplying the nitrogen values by a factor of 6.25. Acid molybdate and Fiske-Subbarow reducer solutions were used to measure the concentration of P through the formation of a phosphomolybdenum complex and the P concentrations in the digested samples were determined through the use of spectrophotometry by measuring the absorbance at 620 nm (method 946.06; AOAC, 2006) using a plate reader (Biotek Synergy Neo2, Biotek Instruments, Winooski, VT, USA). The crude fibre, ADF, and NDF contents were determined using a fibre analyser (Ankom 200 Fiber Analyzer, Ankom Technology, Fairport, NY) and a filter paper technique (Van Soest et al., 1991). The L* (lightness), a* (redness), and b* (yellowness) values of the DDGS samples were measured in triplicate using a Minolta chromameter (Minolta ChromaMeter CR-300, Milano, Italy). In brief, the samples were placed in a petri dish (90 mm diameter) to a depth of approximately 2 cm before colour measurements were taken. Measurements were taken from 3 different locations on the outer surface of each DDGS sample. The AR for each sample was determined in triplicate by funnel test and used as an indicator of the flowability characteristic. A fixed funnel tip with a height of 2 cm from the horizontal surface was used to determine the AR value of each sample. The diameter of the funnel, its extension, and its total length were 18, 21, and 29 cm, respectively. A quantity of DDGS from each sample was allowed to flow through the funnel on to a filter paper until the apex of the pile beneath came into contact with the lower tip of the funnel. Then, the loose portion of the DDGS sample on the filter paper was marked with a pencil and the pile was removed. The diameter of the formed pile was measured DDGS AND FLOWABILITY 197 twice (horizontally and vertically) and its average was taken. This process was repeated three times and the average diameter (d) and radius (r = d/2) were calculated. Based on the height of the funnel and the radius determined, AR was calculated by taking the inverse tangent (tan) of the height (h) of the pile to the r of the pile [(AR = tan(h r)] (Joshi et al., 1993; Aliyu et al., 2010). The DDGS samples were evaluated for BD, tapped density (TD), mean bulk density (MBD), and compressibility in triplicate. The aerated bulk density (kg m) was calculated by dividing the weight of the feed sample (15 g) by its volume using a measuring cylinder. The tapped density (kg m) was obtained after rotating a graduated cylinder (100 ml) containing a DDGS sample (15 g) using a vortex mixer for 2 min and then mechanically tapping it until no further volume change occurred. The mean bulk density (kg m) was obtained by taking the average of BD and TD. The Hausner ratio (HR) was defined as the TD divided by BD. The compressibility (C) of the samples was calculated by using the Carr index formula (

Ash from Jerusalem artichoke and biopreparations enhance the growth and physiological activity of sorghum and limit environmental pollution by decreasing artificial fertilization needs

Abstract: One of the most important necessities in the contemporary economy is to reduce greenhouse gas emissions through the use of biomass as a raw material for obtaining energy instead of fossil fuels. Another goal is to lower soil contamination by decreasing synthetic fertilization through the use of natural fertilizers that do not pollute the environment. These requirements are driving the development of new plant cultivation technologies which allow for the attainment of the maximum yield of biomass convertible to energy and decrease environmental contamination (Faaij, 2006; Biofuels in the EU, 2006; Biofuels Progress Report, 2007; Fernando et al., 2018). It is assumed that the limitation of the contamination of the agrological environment, caused by the use of excessive doses of synthetic fertilizers and pesticides, can be reduced through plant fertilization with ash from the burnt biomass of plant species containing no toxic substances. Due to the fact that this ash may contain the majority of elements necessary for plant growth and is environmentally benign, its use in agriculture as a fertilizer may be beneficial. Moreover, such an application of ash could solve the problem of its storage, which is dangerous for the environment (Romanowska-Duda et al., 2019b). The use of biomass ash in agriculture as an organic fertilizer and an alternative to chemical soil enrichment may be very advantageous in global plant production from an economic © 2020 Institute of Agrophysics, Polish Academy of Sciences Z. ROMANOWSKA-DUDA et al. 366 and environmental point of view and thus appropriate technologies for its application should be developed. This is particularly important since there are predictions that the amount of biomass converted into electricity will continue to grow, already in 2020, electricity production from biomass will be higher by 25%, compared to 2010. The literature concerning the use of ash from burnt biomass is inadequate and treats this problem in a compartmentalized fashion. In the majority of cases, it concerns the use of ash from burnt wood which originates from forestry. This ash may contain toxic substances absorbed by the trees during their long period of growth (Santalla et al., 2011; Vassiliev et al., 2013). Buss et al. (2019) indicated that the application of wood ash could provide nutrients and increase the pH of forest soil and it could also temporarily change its chemistry within a relatively short period of time. Jagodzinski et al. (2018) demonstrated the positive effect of ash from burnt wood on Lemna minor L. development, whereas Romanowska-Duda et al. (2019c) showed the stimulating influence of sorghum ash on the development and physiological activity of Lemnaceae. Piekarczyk et al. (2014), Ciesielczuk et al. (2011) and Meller and Bilenda (2012) demonstrated the increased content of nutrients in soil fertilized with ash from burnt plant biomass including barley, wheat and rape. Schiemenz and Eichler-Löbermann (2010) and Schiemenz et al. (2011) have revealed different structures of ash which depend on the plant species burnt, while Park et al. (2005) have shown that the composition of ash from wood was not consistent during three years of research. It is assumed that the use of ash from burnt biomass is more satisfactory than the use of sewage sludge, which may contain not only nutrients important for growth but also toxic substances which must be removed before its use in plant cultivation (Fang et al., 2017; Pszczółkowska et al., 2019). Because of the inadequate and sometimes inconclusive information concerning this subject, further research is required to explore the influence of ash from particular plant species on different crops under specific soil conditions. Moreover, information concerning the use of plant biomass ash as an alternative to artificial fertilizers, which is the key to decreasing agro environment pollution, is difficult to find in the literature. The possibility of decreasing chemical fertilization through the foliar application of microalgae was demonstrated by Pszczółkowska et al. (2019), Dębowski et al. (2018) and Grzesik et al. (2017a). To the best of our knowledge, a study concerning the use of ash from burnt Jerusalem artichoke in sorghum crops, separately or combined with waste from biogas plant and biopreparations, as well as their impact on plants and soil properties under the conditions of limited artificial fertilization has not been performed to date. Sorghum (Sorghum bicolor L.) variety Rona 1 was selected for the research presented, because this plant is a novel crop with a bright future in Poland and is cultivated for silage and energy production in a changing climate (Krzystek et al., 2018). The aim of the presented research was to assess the possibility of decreasing artificial fertilization by using ash from burnt Jerusalem artichoke, waste from biogas plants, Apol-Humus and Stymjod. Therefore, the impact of these fertilizers on soil properties and on the development and physiological activity of sorghum under reduced doses of artificial YaraMila Complex was studied. MATERIAL AND METHODS Commercial seeds of sorghum (Sorghum bicolor L.) ‘Rona 1’ were obtained from a distributor, Kutno Sugar Beet Breeding Company (Poland). The chemical fertilizer YaraMila Complex (Yara), is commercially available in stores with gardening supplies. The ash came from burning fully matured Jerusalem artichoke plants as part of own research. It was sifted on sieves (with 2 x 2 mm mesh) before use. Three-year studies showed that the ash prepared in this way was uniform and had a similar effect on plant growth. Thus, from a practical point of view there was no need to divide it into additional factions. Noncentrifuged waste from corn grain biodigestion to methane was obtained from Gamawind Ltd., Piaszczyna, Poland, a distillery integrated with a biogas plant. Apol-Humus, a soil improver, was supplied by the manufacturer Poli-Farm Sp. z o.o., Poland, whereas Stymjod, a nano-organic-mineral fertilizer, was supplied by the producer, PHU Jeznach Ltd., Poland. The soil, used for filling 5-litre pots and in field plots was characterized as podzolic. To demonstrate the beneficial effect of applied fertilizers regardless of the climate and conditions of sorghum cultivation, the studies were performed in diverse weather conditions in Central Poland, where the plants were cultivated in 5 L pots and also in the north of the country in a field. In Central Poland, the temperature in July usually fluctuates from 8 to 32°C, average annual precipitation is 528.3 mm and more frequent sunny days with drier air are noted than in North Poland where the average temperature ranges from 11 to 21°C, precipitation reaches 655 mm and moist air from the nearby Baltic Sea is observed. All soil and plant treatments and their assessments were performed over the same time period. The research was performed simultaneously in three experimental blocks, all in the two localities mentioned above and in 3 repetitions. In the second decade of April, the soil in each block was enriched with the synthetic fertilizer YaraMila Complex (YMC) at a dose of 0, 150 or 300 kg ha, the latter one was recommended by the producer. Each block, was fertilized to a different extent with YMC, and consisted of 8 plots, each containing 10 plants grown separately in 5 L pots (pot experiment in Central Poland) or 6 plots with a size of 3x3 m (field experiment in North Poland). At the end of April, the soil in each subsequent plot within every block was fertilized as follows: ASH FROM JERUSALEM ARTICHOKE AND BIO-PREPARATIONS ENHANCE THE GROWTH OF SORGHUM 367