Showing papers in "International Agrophysics in 2008"

Prediction of cetane number of biodiesel fuel from the fatty acid methyl ester (fame) composition

Abstract: Cetane number is an important parameter in evaluating the quality of biodiesel fuel Its determination is usually arduous and expensive, and the results obtained are not always accurate due to experimental error This work is aimed at deve- loping a relationship between the fatty acid methyl ester (FAME) composition and the cetane number (CN) Data were collected from the literature on the cetane number of various biodiesel fuels and their FAME composition A regres- sion analysis was performed on pure FAME to establish a rela- tionship between the cetane number and FAME composition An equation was developed relating the cetane number with the % composition by weight of FAME of biodiesel fuel The pre- dicted cetane number values compare well with the average measured cetane number values This work establishes the general dependence of cetane number on FAME composition of biodiesels

Extraction and characterization of seed oils

Abstract: A b s t r a c t. All the seeds examined in this project have been shown to contain varying levels of oils, mainly in the range of 26-42%, with the exception of Detarium microcarpum which contains about 7% of oils. Characterization of the oils by standard techniques suggest that they contain high levels of saturated fatly acids, judging by their low iodine values (IV) which did not exceed 88 in all cases. They are, hence, not suitable as alkyd resins for paint formulation but may, however, be used for soap production judging by their high saponification values (SV) in the range of 199-261. Lophira lanceolata showed considerable reduction in IV and increase in PV over a period of one month under storage conditions of light , darkness and refrigeration. In light, the IV value of 65 dropped by 50% at the end of one month, while under the same conditions the PV increased by almost tenfold. Less profound changes in both/V and PVwere observed for oil stored in darkness and under refrigeration. The observed profound changes were explained as arising from oxi- dative rancidity of the oils. The nutritional non-oil residue of Lophira lanceolata may be suitable as animal feed judging by the balance of its nutrient composition.

Physical and mechanical properties of soybean

Abstract: Thephysical and mechanical properties of soy- bean were determined at 8 to 16% moisture content. In this moistu- re range, grain length, width, thickness, arithmetic average diame- ter and geometric average diameter increased from 7.24 to 8.19, 6.79-7.12, 5.78-6.23, 6.60-7.18, 6.57-7.14 mm, respectively. The volume of grain and area of grain surface increased linearly from 130.97 to 160.32 and from 125.46 to 144.39 mm 2 , respectively. The sphericity, bulk density, true density and porosity decreased linearly from 0.91 to 0.87, 766.12-719.00, 983.33-905.67 kg m -3 and 22.58 to 20.61%, respectively. The angle of internal friction in- creased linearly from 27.37 to 31.81 with the increase of moisture content. The static coefficient of friction increased from 0.385 to 0.571, 0.304-0.441 and 0.164-0.286 for concrete, wood and galva- nized steel surfaces, respectively.

Effect of spent engine oil on soil catalase and dehydrogenase activities

Abstract: Theeffect of spent engine oil on soil pH as well as activity of selected enzymes (catalase and dehydrogenase) was studied. The results indicate that spent engine oil caused a slight change in soil pH relative to the control. There was a significant decrease (p<0.05) in catalase activity in contrast to a significant in- crease (p<0.05) observed in dehydrogenase activity. On the whole the data suggest that spent engine oil alters soil biochemistry.

Some physical properties of simarouba fruit and kernel

Abstract: Physical properties are often required for the development of post harvest equipment. The study was conducted to investigate the physical properties of Simarouba glauca L. fruit and kernel, namely, dimensions, 1000 unit mass, fruit part fraction, arithmetic mean diameter, geometric mean diameter, surface area, sphericity, aspect ratio, bulk density, true density, porosity and angle ofrepose. The kernel had 8.51% (w.b.) moisture and 61.04% oil content, which is higher than the fruit and shell. The average fruit length, width, thickness and 1000 unit mass were 21.26,13.81, 11.03 mm; and 1120.16 g, while the corresponding value for kernel were 13.78,7.77,6.71 mm; and 330.26 g, respectively. The sphericity and surface area of fruit were 5.8 and 63.36% more, respectively, than those of kernel. Bulk densities of fruits and kernels were 622.27 and 727.73 kg m -3 , the corresponding true densities were 931.96 and 1019.3 kg m -3 , and the corresponding porosities were 33.23 and 28.61%, respectively. The angle of repose of fruit and kernel were 31.35 and 35.02°, respectively.

Some physical properties of date fruit [cv. Dairi]

Abstract: Most of the date fruit processing methods employed are still traditional. It becomes imperative to characterize the fruits with a view to understand the properties that may affect the design of machines to handle their processing. Objectives of this study are to present basic principles of physical properties of date fruit (cv. Dairi) in order to facilitate the design of some machines for its processing. Dry-basis moisture content of date fruit was found to be 10.45% (10.88% for pitted dates and 7.87% for their pits). Other results showed that linear dimensions varied from 29.8 to 40.2 mm in length, 15.7 to 20.2 mm in width, and 15 to 19.7 mm in thickness. Mean mass and volume of fruit were measured as 5.30 g and 5.49 cm 3 , respectively. The projected areas along length (PL), width (Pw) and thickness (P T ) were 262.71,498.1, and 513.1 mm 2 , respectively. The fruit density and pitted fruit density were measured as 0.97 and 1.18 g cm -3 , while bulk density and porosity were 0.49 g cm -3 and 49.14%, respectively. The geometric mean diameter, sphericity and surface area were obtained as 22.38 mm, 0.63, and 1577.84 mm 2 , respectively. The mean coefficients of static friction were measured as 0.27, 0.32 and 0.4 on plywood, galvanized iron steel, and glass surfaces, respectively.

Representation of He-Ne laser irradiation effect on radish seeds with selected germination indices

Abstract: Inthis paper the effect of He-Ne laser irradiation of radish seeds as a potential means to accelerate the germination rates have been investigated. We examined whether the change of final germination percentage (FGP) of irradiated seeds is accom- panied by changes of other germination indices. Germination tests were carried out at the temperatures of 15 and 20oC, and the se- lectedgerminationindiceswere:meangerminationrate,meanger- mination time, relative frequency, time for the first seed to germi- nate, time to reach 50% germination, time between 25 and 75% and time between 10 and 90% of final germination. The results showed that He-Ne laser light irradiation could significantly affect the FGP when compared to the control seeds, although these depended on the germination temperature. The irradiation improves the FGP only at 20oC, although there were no differences detected in any other examined germination indices. The results led to the conclu- sion that irradiation did not affect any time-related properties describing the germination process. A simple comparison of the FGP of control and the irradiated seeds was found to be the only germination index which indicated the influence of He-Ne laser irradiation on germination.

Soil physical properties under winter wheat grown with different tillage systems at selected locations

Abstract: The aim ofthis research was to determine in 2006 and 2007 the effects of different tillage systems on the soil physical properties: bulk density, water content and stability. Analyses of physical properties of soil were performed on the long-term field experiment at the IUNG-PIB Experimental Station in Grabow (Mazowieckie voivodeship) on a heavy loamy sand and on a pri- vate farm in Rogow (Lublin voivodeship) on a silt loam soil. Winter wheat was grown in traditional and reduced tillage systems: 1) traditional tillage (TT) with surface mulching (chopped wheat straw) based on mouldboard ploughing (to 25 cm depth) and traditional soil management equipment, and 2) reduced tillage (RT) with surface mulching (chopped wheat straw) based on soil crushing-loosening equipment and a rigid-tine cultivator (to 10 cm depth). Soil physical properties were measured on samples coll- ected from the field throughout the growing season. These in- cluded: particle size distribution (hydrometer method), soil water content and bulk density measured using 100 cm 3 cylinder samples (after drying at 105C for 48 h). For the above, four replicates were collected from each of the following depths: 2-8, 13-18, 28-33, 47-53 and 67-73 cm. Soil stability was measured with a turbi- dimetric method using samples from 5-10, 15-20 and 30-35 cm depths. Soil stability was measured in terms of the content of readily-dispersible clay (RDC) in the soil samples. RDC was measured using a turbidimeter. Ten replicates were used for each soil and depth at each place. The effect of the tillage system on the values of the physical properties was significant at both sites. Reduced tillage resulted in increased water content throughout the whole soil profile at Rogow. However, at Grabow, this effect was found only at the top depth. Also reduced tillage increased bulk density in both soils, especially in the 2-8 and 13-18 cm depth layers in comparison with traditional tillage. Reduced tillage reduced the amount of RDC and therefore increased soil stability, especially in the top layer (5-10 cm) in comparison with traditional tillage. The results showed that the reduced tillage system created a more-friendly environment for soil physical properties - particularly soil stability than the conventional system.

Evaluation of carbon sequestration in energetic crops (Miscanthus and coppice willow)

Abstract: The aim of theproject was analytical evaluation of carbon content and soil carbon sequestration in Miscanthus and coppice willow crops biomass. In this paper, we present the results from a field experiment carried out in 2004-2006 at two Experimental Stations of the Institute of Soil Science and Plant Cultivation, Pu³awy, and net C sequestration under this cultivation. The C-sequestration model adapted by Matthews and Grogan (2001) was used for the simulations. The abovementioned crops are cultivated for the pro- duction of solid fuels. The three-year average yield for Miscanthus was between 15 and 17 t ha -1 y -1 , dependent on location, whereas for willow it was 12 and 13 t ha -1 y -1 . The net soil carbon sequestration for Miscanthus cultivation was 0.6 4tCh a -1 y -1 while for coppice willow it was 0.3 0tCh a -1 y -1 .

Strain-dependent variations in attachment of E. coli to soil particles of different sizes

Abstract: Attachment of E. coli to soil particles affects bacteria transport in overland flow and in soil. The objective of this research was to investigate the existence of strain-dependent varia- tions in attachment of manure-borne E. coli to soil particles of different sizes using repetitive sequenced-based PCR techniques. Tyler clay loam soil was fractionated to obtain particles of coarse sand, medium sand, fine sand, silt, and clay sizes. The inoculum for attachment studies was produced by culturing aged manure. Serial dilutions of the fecal coliform suspension (10 2 and 10 3 CFU ml -1 ) were mixed with soil particle fractions. After incubation, soil- bacteria suspensions were centrifuged, and DNA was extracted from supernatants to be used for polymerase chain reaction (PCR) with ERIC primers. The DNA fingerprint analysis was done with pseudo-gel images from electrophoregrams using BioNumerics. Cluster analysis led to identification of five clusters with the simi- larity level within them higher than 80% and 17 clusters with the similarity level within them higher than 90%. The chi-square test was applied to test the hypothesis that the strain distribution among the clusters does not depend on adsorbent. This hypothesis could be rejected at 0.0001 probability level. The preferential attachment of different strains to particles of different size classes may be attributable to differences in both particle surface and bacteria surface properties. Because the attachment to mineral surfaces for pathogenic E. coli strains may be different from that for non-patho- genic strains, more information on attachment pathogenic E. coli to suspended solids in overland flow attachment needs to be col- lected, as the differences in attachment may result in differences in overland transport of pathogenic and non-pathogenic E. coli.

Some physical and hydrodynamic properties of two varieties of apple (Malus domestica Borkh L.)

Abstract: Several physical and hydrodynamic properties of two apple varieties (Redspar and Delbarstival), newly planted varieties in Iran, were determined and compared. These properties are necessary for the design of equipments for harvesting, proces- sing, transporting, sorting, separating and packing. Some physical characteristics such as: average fruit length, width, thickness, the geometric, arithmetic and equivalent mean diameter, projected area, surface area, sphericity index, aspect ratio, fruit mass, volume and moisture content were studied. These values were different statistically at 1% level of significance for both cultivars. The terminal velocity, coming up time, bounce and drag forces for Red- spar variety were 0.47 m s -1 , 2.33 s, 2.69 and 0.46 N, respectively. But in the case of Delbarstival variety, 0.42 m s -1 , 2.52 s, 1.40 and 0.24 N were as terminal velocity, coming up time, bounce and drag forces, respectively. The packaging coefficient was 0.62 and 0.53 for Redspar and Delbarstival varieties. The published comparison of data, which might be useful to engineering equipment design for the apple varieties, was generally found to be statistically different.

Effect of hulling and milling on the physical properties of rice grains

Abstract: Basic physical properties of agricultural materials play important role for optimizing the design of equipment and fa- cilities for the harvesting, handling, conveying, separation, drying, storing, and processing. In this study, some physical properties of three rice varieties, namely Tarom Mahali, Fajr, and Neda, at three levels of processing, which name rough rice (paddy), brown rice (husked or hulled), and white rice (milled) were investigated. The thousand grains mass and porosity decreased significantly with the rice processing, but the bulk density increased. The rough rice of each variety showed the least value of true density. Unit mass and volume of rice grain decreased with the rice processing. Totally, the static coefficient of friction affected by cultivars, levels of pro- cessing, and frictional materials. By processing, the filling angle of repose for all cultivars decreased. The terminal velocity increase significantly for every variety. It was observed that the terminal velocity of the rice's hull and bran is lower than for the rough rice, brown rice, milled rice.

Some postharvest physical properties of Iranian apricot (Prunus armeniaca L.) fruit

Abstract: Some of the postharvest physical properties of six cultivars of Iranian apricot fruits are presented in this study. Information about these properties is very important for understanding the behaviour of the product during the postharvest operations, such as harvesting, transporting, sorting, grading, packaging and storage processes. This research was undertaken to study some physical properties of six Iranian apricot cultivars (Shams, Nakhjavan, Djahangiri, Sefide Damavand, Shahroud-8, and Gheysi-2). These properties include: linear dimensions, geometric mean diameter, projected area, criteria projected area, surface area, sphericity, volume, mass, bulk and average fruit density, packaging coefficient, coefficient of static friction, and ratio of length to width (L/W), length to thickness (L/T), and length to mass (L/M).

Thermal properties of guna seed

Abstract: Thespecific heat, thermal conductivity and thermal diffusivity of whole and ground guna seed and kernel were evaluated and their change with moisture content and temperature investigated. The specific heat of whole and ground seed increased from 1391.1 to 3020.13 and from 1459.14 to 3058.15 J kg -1 K -1 , respectively, as the moisture content and temperature increased from 4.7 to 25.35% (d.b.) and 307.12 to 368 K. The specific heat of whole and ground kernel also increased from 2135.15 to 4275.56 and from 2173.4 to 4340.06 J kg -1 K -1 , respectively, as the moisture content and temperature increased from 5.6 to 19.13% (d.b.) and 308 to 368 K. The thermal conductivity of whole seed and kernel increased from 0.0711 to 0.1282 and 0.087 to 0.126 W m -1 K -1 , respectively, as the moisture content and temperature increased. Thermal conductivity of ground seed and kernel increased also from 0.1 25 to 0.223 and 0.107 to 0.191 W m -1 K -1 , respectively, as the moisture content and temperature increased. The thermal diffusivity of whole seed and kernel decreased from 8.5 10 -8 to 9.311 10 -8 and 3.42 10 -8 to 4.397 10 -8 m 2 s -1 , respectively, as the moisture content and temperature increased. The thermal diffu- sivity of ground seed and kernel decreased from 3 10 -7 to 8.468 10 -8 and 1.768 10 -7 to 4.214 10 -8 m 2 s -1 , respectively, as the moisture

Soil quality assessment using fuzzy modeling

Abstract: Maintaining soil productivity is essential if agriculture production systems are to be sustainable, thus soil quality is an essential issue. However, there is a paucity of tools for measurement for the purpose of understanding changes in soil quality. Here the possibility of using fuzzy modeling theory as a means to address the problem of soil quality assessment is considered. For soil quality assessment, two general types of fuzzy soil quality indicators potentially could be defined. The theoretical consideration of this process is illustrated with an example. Results indicate that the fuzzy multi-attributive approach could be effectively utilized as a tool leading to better understanding soil quality.

Moisture dependent physical properties of red bean (Phaseolus vulgaris L.) grains

Abstract: Physical properties of food materials like grains are important in the design or improvement of harvesting and processing machines. This study was aimed at assessment of some physical properties of red bean grains as a function of moisture content. Based on the results obtained, with increasing moisture content, grain dimensions as well as thousand grain mass in- creased. In the moisture content range of 10 to 20% w.b., the surface area, true density, and porosity values increased by 10.6- 19.7, 4.76-6.24, and 17.91-21%, respectively. This increase in moisture content caused a decrease in bulk density values by 8.35 and 9.70% for the varieties of Goli and Akhtar, respectively. Coefficient of static friction (Goli and Akhtar) increased against surfaces of rubber (27.3 and 27%), galvanized iron (50 and 28.5%), and plywood (32 and 21.4%) as the moisture content increased. Mechanical properties were determined in terms of average rupture force, deformation at rupture point, and rupture energy. Defor- mation and rupture energy of red bean grains generally increased in magnitude with an increase in moisture content, while rupture force decreased.

Some mechanical properties of barberry

Abstract: A b s t r a c t. In this study some mechanical properties of barberry have been evaluated as a function of barberry moisture content varying from 53.11 to 89.23% w.b. The mechanical properties of barberry were determined in terms of average rupture force, deformation and toughness. Samples at various moisture contents were compressed along axis through the width dimension. Physical properties of barberry such as dimensions and geometric mean diameter and volume were determined. In the moisture range from 53.11 to 89.23% w.b., length, width, thickness, geometric mean diameter and volume increased. Deformation increased from 0.340 to 2.381 (mm) as the moisture content increased from 53.11 to 89.23% w.b. Rupture force and toughness decreased from 47.238 to 19.669 (N) and 1.149 to 0.105 (J cm -3 ), respectively. The

Some physical properties of wild pistachio (Pistacia vera L.) nut and kernel as a function of moisture content

Abstract: Inorder to design equipment for improved processing of wild pistachio (Pistacia vera L.), some of the engine- ering properties were determined as a function of moisture content. The average length, width and thickness of wild pistachio nuts at 5.83% moisture content (w.b.) were 13.98, 8.76 and 7.25 mm, while the corresponding values of kernels at 6.03% moisture content (w.b.) were 11.07, 5.92 and 4.83 mm, respectively. The bulk and true densities of wild pistachio nut and kernel increased with increase in moisture content, while porosity decreased. At all moisture contents, the static coefficient of friction was the highest for wild pistachio nut and kernel on rubber and the least for glass. The results of this research indicated that the filling and emptying angle of repose of nuts and kernels increased as the moisture content increased in the range studied.

Deformation and fracture of dika nut (Irvingia gabonensis) under uni-axial compressive loading

Abstract: Fracture behaviour of dika nut under quasi-static loading along the longitudinal axis and the transverse axis was investigated. The fracture resistance of the nut was measured in terms of average force, deformation and toughness at nutshell fracture, and nut stiffness. Physical dimensions and shape of the nut, to provide for complementary input in design of handling equipment, were also determined. The force required to crack the nut increased with nut diameter but was not significantly different in both loading orientations. The mean cracking force was in the range of 2.06 to 3.67 kN. The compression of the nut exhibited a pro- nounced linearity between load and deflection. Dika nuts loaded along the transverse axis required less energy for nutshell fracture than those loaded along the longitudinal axis. Minimum toughness occurred with the small size nuts loaded along the transverse axis, thus providing base-line data in future design of an appropriate nutcracker.

Soil properties influencing water-dispersible clay and silt in an Ultisol in southern Nigeria

Abstract: Soil degradation such as soil erosion by water is directly linked to water-dispersible clay (WDC) in the soil. Ten locations in an Ultisol in southeastern Nigeria were sampled for analysis. In each locations 2 samples were collected viz; 0-20 and 20-40 cm depth. The aim was to measure the water-dispersible clay and silt and determine the easily measured soil properties that influence clay dispersion in the soils. The soils investigated are porous, high in soil bulk density and low available plant nutrient. Soils are all within the acid range in pH while the soil organic carbon (SOC) contents are low. The exchangeable Ca 2+ and Mg 2+ contents of the soils dominated the exchange complex. Values of WDC are between 60 and 120 g kg -1 with a mean value of 73 g kg -1 . Also water-dispersible silt (WDSi) ranged from 10-190 g kg -1 with a mean of 66.5 g kg -1 . These results indicate that pH, SOC, exchangeable Ca 2+ , exchan- geable acidity (EA), CEC, sodium adsorption ratio (SAR), the clay and silt contents of these soil are the soil factors that influence the water-dispersible properties of the soils. The modifications of the regular management procedures of the soils through the addition of soil organic matter will check the rate of WDC in the soils and that will accordingly check the high degradation rate of the soils.

Effects of turning frequency on composting of chicken litter in turned windrow piles

Abstract: A b s t r a c t. Composting of chicken manure mixed with sawdust (chicken litter) was performed using the turned windrow method. The aim was to investigate the effects of turning frequency on some physicochemical properties of chicken litter. The three turning frequency treatments were: no turning, turning every 3 days and every 7 days. The initial physicochemical properties of chicken litter were determined. The moisture content of the treatments was adjusted to 55% (w.b.) at the beginning of composting and no moisture adjustment was done thereafter. The results showed that turning frequency did not affect (P > 0.05) pH, temperature, rate of composting and maturation time, but it affected (P < 0.05) moisture content, dry matter, total carbon, total nitrogen and carbon to nitrogen ratio of composting piles. Losses were observed in moisture content (61.82-75.8% of the initial moisture content), dry matter (7.68-13.01% of the initial dry matter), total carbon (51.71-62.24% of the initial total carbon) and total nitrogen (45.36-79.61% of the initial total nitrogen). The losses of total carbon were attributed to organic matter degradation, while those of total nitrogen were largely attributed to ammonia (NH 3 ) volatilization. Moisture loss and C:N ratio increased as turning frequency increased. All the treatments reached maturation at about 70 days, when the pile temperatures dropped to near ambient temperature. C:N ratio increase and losses in total carbon and total nitrogen were significantly higher in the turned windrows (treatments TF7 and TF3) than in the unturned windrow (treatment TF0). In conclusion, the short maturation time was attributed to low moisture levels in the piles.

Determination of Poisson's ratio and elastic modulus of African nutmeg (Monodora myristica)

Abstract: A b s t r a c t. An investigation into the Poisson’s ratio and elastic modulus of African nutmeg as a function of moisture content and loading rate was carried out. Quasi-static compressive tests were conducted at moisture levels of 8, 11.2, 14, 17.4 and 28.7% (d.b.) in an axial loading orientation. Both unit lateral extension and unit normal compression values were determined. Average values of 0.512 to 0.275 were obtained for moisture levels of 8 to 28.7%, respectively. Effects of loading rates were also investigated and results show that Poisson’s ratio increased from 0.136 to 0.334 at loading rates of 1 and 7 mm min -1 , respectively. Elastic modulus was observed to decrease as moisture increased. Average values of 201.5 to 41.30 N mm -2 were noted for moisture levels of 8 to 28.7%, respectively. A similar negative trend was observed with loading rate. These finding could therefore be useful in predicting the load deformation behaviour of African nutmeg.

Emission of greenhouse gases and soil organic matter balance in different farming systems

Abstract: Estimation of the influence of different farming systems on emission of greenhouse gases (methane and nitrous oxide) was the aim of the research. The research was conducted on the basis of a special field experiment established in 1994 in the Experimental Station in Osiny in which different crop production systems are compared, and in a group of 20 organic farms organic farms located in the central part of Poland. For the first object the analysis of nitrous oxide emission and soil organic matter balance was done for 1996-2007, whereas for the second one CH4 and N2O emission and potential of sequestration of CO2 in soil organic matter was done for 2004-2005. Organic farming system was characterized by significantly lower nitrous oxide emission in comparison to other systems. There was no distinct difference in CH4 emission between compa- red systems. In the organic farms, total CH4 and N2O emission ex- pressed in GWP units amounted to 1623 points and this was 22% less than the average value for the Kuyavian-Pomeranian voivode- ship. Balance method showed that organic system has a great potential in sequestration of CO2 in soil organic matter in com- parison to integrated and conventional systems. However, measu- rements of humus content in soil did not confirm that observation. K e y w o r d s: organic farming, greenhouse gases, methane, nitrous oxide

Land use planning in Ahar area (Iran) using MicroLEIS DSS

Abstract: Thedecision support system, MicroLEIS DSS, was applied to evaluate the land use planning in Ahar area, East Azarbaijan. In this way 6 agro-ecological land evaluation models constituents of this DSS software were selected in order to make strategies related to land evaluation at a regional level, such as segregation of agricultural lands, restoration of marginal areas, diversification of crop rotation, and identification of vulnerability areas. Results obtained from each evaluation models are presented and discussed in this research work. Soil morphological and analytical data were collected from 44 soil profiles representative of the study area and stored in SDBm plus database. Three control sections: 0-50, 25-50, and 0-100 cm were calculated by 'soil layer generator' to apply and run the models. Results show that in Ahar area, 45% of the total extension was classified as good capability land for agricultural uses. However, almost 12% of total area must be reforested by suitable shrub species, and not dedicated to agriculture, to minimize the land degradation. Additionally, soils with vertic properties used to present an excellent capability for most of the traditional crops. Wheat-alfalfa-soybean was selected as the best crop rotation. In summary, MicroLEIS DSS tool appears to be useful in semi-arid regions, such as East Azarbaijan (Iran), to formulate sustaining agro-ecological systems. K e y w o r d s: decision support tools, MicroLEIS DSS; SDBm plus, semi-arid, sustainable use

Oil point pressure of cashew (Anacardium occidentale) kernels

Abstract: Theeffects of moisture content (4, 6, and 8%), heating temperature (70, 85, 100, and 115 o C) and heating time (15, 25, 35 and 45 min) on the oil point pressure of coarsely ground and finely ground cashew kernel aggregates were investigated using a laboratory press. For aggregates it was observed that oil point pressure decreased significantly with increase in moisture content, heating temperature and heating time. The lowest oil point pressure values obtained were 0.1572 MPa (for fine cashew kernel aggre- gates at a moisture content of 4% heated at 115C for 45 min) and 0.1664 MPa (for coarse cashew kernel aggregates at a moisture content of 6 % heated at 100°C for 45 min). For both particle sizes at moisture content >8 % and heating temperature >100 o C, the dead weight of the hydraulic press was sufficient to bring oil out of the oil bearing cells.

Microbiological indices of soil quality fertilized with dairy sewage sludge

Abstract: Thestudy was performed on a pot experiment in which a grey-brown podzolic soil was amended with two different doses of dairy sewage sludge (30 and 75 t ha -1 ) - 1 and 25% of DSS During periode of incubation in different terms of analyses (7, 14, 30, 60, 90 and 120 days after the incorporation of dairy sewage sludge) the following analyses were done: so-called total number of bacteria, so-called total number of filamentous fungi, number of cellulolytic bacteria, respiration activity and dehydro- genase activity Dairy sewage sludge applied to the soil caused stimulation of the total number of bacteria, fungi and cellulolytic bacteria and respiration activity and inhibition of dehydrogenase activity in a grey-brown podzolic soil

Soil moisture storage and water-use efficiency of maize planted in succession to different fallow treatments**

Abstract: Soil water storage and crop water use efficiency (WUE) were monitored in a randomised complete block design experiment set up on a 0.7 ha field plot with treatments that consisted of five fallow treatments, namely Guinea grass (Panicum maximum Jacq.PAF), Kaliko plant (Euphorbia heterophylla Linn. EUF), tropical kudzu (Pueraria phaseoloides(Roxb) Benth.(PUF), native fallow without fertilizer (NNF), and native fallow with fertilizer applied during subsequent cropping (NFF). The fallow crops were ploughed under and cultivated to maize (Zea mays )i n the subsequent season and the water storage and crop water use efficiency were monitored. Fluctuations in soil water storage were found to be dependent on rainfall and soil profile characteristics. The amount of water stored in the soil was consistently the highest under NNF (25%) and the least under PUF (19%). Maize dry matter yield (0.46 - 3.38 t ha -1 ) and WUE (0.011 t ha -1 mm -1 - 0.030 t ha -1 mm -1 ) were the highest at 29 days after planting (29 DAP) and at 45 DAP under TPU. At 75 DAP dry matter yield for EUF improved (8.88 t ha -1 ), while NFF was the highest (10.12 t ha -1 ). Water use efficiency calculated in terms of grain yield (WUE-GY) having a value of 0.018 t ha -1 mm -1 was found to be the highest under NFF, followed by the results from EUF and PUF (0.015 t ha -1 mm -1 ), while NNF (0.011 t ha -1 mm -1 ) was significantly (p 0.05) the lowest. Short fallow with Pueraria phaseoloides, therefore, appeared to be an attractive alternative for sustaining the water use efficiency of continuously cropped farmlands.

Effect of extremely high frequency electromagnetic fields on the microbiological community in rhizosphere of plants

Abstract: Electromagnetic fields (EMF) are widely used to stimulate germination of seeds, improve their quality and speed up the growth of plants. This research was aimed at investigation of the influence of EMF and extensively used seed disinfectant (thiram) on the content of rhizosphere microflora of Pinus sylvestris seedlings. For this purpose, pine seeds were treated with EMF (alone or in combination with thiram), and the rhizosphere microflora was analysed. Various growth media were used to classify bacteria originated from pine rhizosphere. We found that EMF treatment resulted in proliferation of agronomically useful microorganisms including nitrogen-fixing ones. The suggested approach allows improving the microbiological content of soils and to avoid the use of a big amount of mineral fertilizers.

Effect of different tillage systems on some microbiological properties of soils under winter wheat

Abstract: The aim ofthis research was to determine the effect of applied tillage systems on changes of chosen parameters of soil microbiological activity. Analyses of microbiological properties of soil were performed on soil samples collected from long-term field experiments at a private farm in Rogow (Lublin voivodeship) on silt-loam soil and at the IUNG-PIB Experimental Station in Grabow (Masovian voivodeship) on heavy loamy sand. Winter wheat was grown in conventional (CT) and reduced tillage (RT) systems. Analyses of soil taken from experimental fields included the rate of CO2 evolution using the titration method; microbial biomass C content using the F-I method; dehydrogenase system activity using TTC as a substrate; microbial biomass N content using the F-E method and the Most Probable Number (MPN) of ammonia- and nitrate-forming bacteria. Applied tillage systems affected significantly the analysed parameters of biological activity of tested soils in both experimental years. In general, at both experimental sites, the numbers of specific groups of soil microorganisms estimated on the quantity of biomass C and N were significantly higher in RT soil than in CT soil (by about 20%, on average) at both depths: 0-15 and 15-30 cm. In 2006 and 2007, the dehydrogenase activity, ammonification and nitrification strength of soil reached the highest values mostly in RT soil at both experimental sites. Calculated higher values of microbial quotient and lower values of metabolic quotient in RT soil indicate that the RT system created a more friendly environment for the growth and activity of soil microorganisms, in comparison with the CT system. Key w ords :microbial respiration, microbial biomass C and N, activity of dehydrogenases, ammonia- and nitrate-forming bacteria, tillage system

Estimation of morphological traits and mechanical properties of grasspea seeds [Lathyrus sativus L.] originating from EU countries

Abstract: The material for the study comprised 30 accession forms of grasspea (Gene Bank in Gatersleben, Germany) originating from four European countries, and two Polish cultivars -Derek and Krab. Estimation of variability of the morphological traits and yield structure was performed on the basis of a field experiment and the obtained seeds were analysed under laboratory conditions, taking into account the geometric features of the seeds and their physical (mechanical) properties as defined by values of static loads. Apart from differences in the dates of start of blooming, plant height, height of positioning of the lowest pod on the plant, and pod morphology (length and width), the plants under study differed with respect to their yield-forming traits, such as the number of pods per plant, number and weight of seeds in pod, and number and weight of seeds per plant. Seeds under analysis, taken for static load tests, were characterised by fairly uniform moisture content within the range from 7.9 to 9.8%. In terms of weight of 100 seeds, the experimental objects displayed a broad range of variability, representing forms typically small-seeded (from 5 to 15 g), medium-seeded (from 15 to 25 g), and coarse-seeded (over 25 g). The coarse-seeded forms originated mainly from Italy and Spain, while those with smaller seeds came from France, Germany and Poland. The above trait was related to the geometric features of the seeds, expressed in terms of their thickness, width and length. The ranges of variability of those features were, respectively, 4.61-6.13,7.13-12.98 and 7.88-14.43 mm. The most extensive ranges of variation were recorded for static loading parameters concerning maximum force and elasticity (N), maximum and elastic strain (mm) and energy (mJ), and apparent modulus of elasticity (MPa). On the basis of the results obtained, forms with the highest and the lowest values of static load were identified. The above traits were related not only with the geometric features of the seeds, but likely also with genetically determined changes in the microstructure of the seeds. Analysis of the microstructure in further research would surely permit demonstration of the relevant relationships with respect to the results obtained from analysis of static loading. The results obtained from the field trial and from estimation of the mechanical properties of the seeds indicate a broad range of variability of the parameters under analysis. This permits to isolate the most valuable foreign genotypes and their further utilisation as parent material for hybridisation aimed at improvement of local forms of grasspea.