Showing papers in "The Journal of Agricultural Science in 2012"

Sprinkle and Trickle Irrigation System Design Using Tapered Pipes for Pressure Loss Adjusting

Abstract: Accurate computing of amount of pressure loss is very important in sprinkle and trickle irrigation system design Not correctly adjusted of pressure loss are causes lack of appropriate performance or failure of sprinkle and trickle irrigation system By tapered pipes, pressure loss adjusted using increasing or decreasing of pressure head In this study using HydroCalc software, ability of single and tapered pipes in pressure loss adjusting has been compared Single and tapered laterals were able to adjusting of pressure loss but single manifolds were not able to achieving to the desired pressure head In single lateral-tapered manifold system due to the lower pressure loss in laterals, can be use from several types of pipe diameters for manifolds but in tapered lateral-tapered manifold system due to the more pressure loss in laterals, the choice is limited The best diameters for tapered manifolds with single lateral were 692-368 mm, 692-582-368 mm, and 582-460-368 mm whereas the best diameters for tapered manifold with tapered lateral were 692-460-368 mm

Comparison of Surface Irrigation Simulation Models: Full Hydrodynamic, Zero Inertia, Kinematic Wave

Abstract: Some phenomena such as surface irrigation are so complex that it is very difficult to implement them in nature. For this purpose, simulation models are used. In this study, ability of full hydrodynamic, zero inertia, and kinematic wave models has been investigated in surface irrigation simulation. Using SIRMOD software, their performance has been compared. The results showed that full hydrodynamic and zero inertia models were very powerful in simulation process. For increasing of filed slope until amount of 0.01 full hydrodynamic and zero inertia models had not any difference but for more increasing of S0 due to the increasing of velocity, accuracy of zero inertia model dropped. In full hydrodynamic and zero inertia models for increase in Manning’s roughness coefficient amount of error was increased until n=0.15. After this amount, error remained constant thus n=0.15 determined as critical discharge. Accuracy of kinematic wave model reduced in clay and heavy clay soils, high discharges, high Manning’s roughness coefficient, and basin irrigation. However, in many situations all three models had the same answers and were capable tools to simulating of surface irrigation processes.

Effects of Different Light Sources on the Growth of Non-heading Chinese Cabbage (Brassica campestris L.)

Abstract: To date, little is known about the effects of different light sources on the growth and quality of non-heading Chinese cabbage (Brassica campestris L.). The objective of present study was to evaluate the effects of light-emitting diodes (LEDs) light sources (blue, blue plus red, red), fluorescent lamps and sunlight on growth and vitamin C, soluble protein, sucrose, soluble sugar, starch and pigment concentrations in non-heading Chinese cabbage seedlings. The dry mass of shoots and the fresh and dry masses of roots were highest in seedlings grown under red LEDs with weak lights. The fresh mass of roots and starch concentration were highest under red LEDs despite of the altered photosynthetic photo flux density (PPFD) levels. The concentrations of chlorophylls and vitamin C were greatest under blue LEDs with altered PPFD levels. The numbers of flower buds and open flowers were highest under red LEDs and blue plus red LEDs and were higher under LEDs than fluorescent lamps. The duration of flowering was highest under red LEDs and blue plus red LEDs. The present results demonstrate that LED light sources are more effective than fluorescent lamps for vegetative and reproductive growth of non-heading Chinese cabbage. Moreover, blue LEDs benefit vegetative growth, while red LEDs and blue plus red LEDs support reproductive growth in non-heading Chinese cabbage. In the artificial cultivation and subsequent transplanting of the life cycle of plants, the light source can be selected to meet the requirements of different growth stages of plants and be used to promote the subsequent process in the industrial production of non-heading Chinese cabbage.

Factors Affecting Farmers’ Adoption of Agricultural Innovations: A Panel Data Analysis of the Use of Artificial Insemination among Dairy Farmers in Ireland

Abstract: The use of artificial insemination (AI) has been of enormous economic benefit for dairy farmers in many countries such as Ireland through the genetic improvement of their stock. Despite these benefits a significant proportion of dairy farmers continue to use natural mating over AI. Previous research has found that the cost of semen, the cost of insemination and success rate all affect the probability of farmers using AI. Using a nationally representative panel dataset, this paper examined if there were any farm or farmer characteristics that affected the probability of dairy farmers using AI. Modelling the farm factors driving the uptake of AI enables the understanding of the differences between various types of landowners which should in turn better equip policymakers to design policies and programs that efficiently promote good reproductive management. The results in this paper suggest that there is significant heterogeneity among farm households in relation to the uptake of AI with both characteristics of the farmer as well as structural farm factors all found to significantly affect the probability of a farmer adopting this agricultural innovation.

Evaluation of Cation Exchange Capacity (CEC) in Tropical Soils Using Four Different Analytical Methods

Abstract: Four analytical methods for determination of cation exchange capacity (CEC) in tropical soils were tested, aiming to define what the most appropriate based on the requirements: analysis time, degree of reliability and cost of operation. A total of 444 soil samples from the Amazon rainforest and Atlantic rainforest were analyzed in eleven soils types. Organic matter, pH and ions Na + , K + , Ca 2+ , Mg 2+ and H + +Al 3+ were also analyzed. The influence of the action of fire on the release of ions to the soil was also tested. The results indicated that there was a momentary increase in CEC in the soil after a fire. Tropical soils have a high humidity and acidity, contributing to an overall increase of CEC. Adverse climatic conditions in the tropics affect soil properties, so that practical methods and low cost have the advantage that they can be applied periodically to analyze the quality of the soil.

Stochastic simulation of the cost of home-produced feeds for ruminant livestock systems

Abstract: An agro-economic simulation model was developed to facilitate comparison of the impact of management, market and biological factors on the cost of providing ruminant livestock with feed grown on the farm (home produced feed). Unpredictable year-to-year variation in crop yields and input prices were identified as quantifiable measures of risk affecting feed cost. Stochastic analysis was used to study the impact of yield and input price risk on the variability of feed cost for eight feeds grown in Ireland over a 10-year period. Intensively grazed perennial ryegrass was found to be the lowest cost feed in the current analysis (mean cost €74/1000 Unite Fourragere Viande (UFV)). Yield risk was identified as the greatest single factor affecting feed cost variability. At mean prices and yields, purchased rolled barley was found to be 3% less costly than home-produced spring-sown barley. However, home-produced spring barley was marginally less risky than purchased barley (coefficient of variation (CV) 0·063 v. 0·064). Feed crops incurring the greatest proportion of fixed costs and area-dependent variable costs, including bunker grass silage, were the most sensitive to yield fluctuations. The most energy input-intensive feed crops, such as grass silage, both baled and bunker ensiled, were deemed most susceptible to input price fluctuations. Maize silage was the most risky feed crop (CV 0·195), with potential to be both the cheapest and the most expensive conserved feed.

Performance of extra-early maize cultivars based on GGE biplot and AMMI analysis

Abstract: Multi-environment trials (METs) in West Africa have demonstrated the existence of genotype×environment interactions (G×E), which complicate the selection of superior cultivars and the best testing sites for identifying superior and stable genotypes. Two powerful statistical tools available for MET analysis are the additive main effects and multiplicative interaction (AMMI) and the genotype main effect+G×E (known as GGE) biplot. The objective of the present study was to compare their effectiveness in identifying maize mega-environments and stable and superior maize cultivars with good adaptation to West Africa. Twelve extra-early maturing maize cultivars were evaluated at 17 locations in four countries in West Africa from 2006 to 2009. The effects of genotype (G), environments (E) and G×E were significant (P<0 01) for grain yield. Differences between E accounted for 0 75 of the total variation in the sum of squares for grain yield, whereas the G effects accounted for 0 03 and G×E for 0 22. The GGE biplot explained 0 74 of total variations in the sum of squares for grain yield and revealed three mega-environments and seven cultivar groups. The AMMI graph explained 0 13 and revealed four groups each of environments and cultivars. The two procedures provided similar results in terms of stability and performance of the cultivars. Both methods identified the cultivars 2004 TZEE-W Pop STR C4 and TZEE-W Pop STR C4 as superior across environments. Cultivar 2004 TZEE-W Pop STR C4 was the most stable. The GGE biplot was more versatile and flexible, and provided a better understanding of G×E than the AMMI graph. It identified Zaria, Ilorin, Ikenne, Ejura, Kita, Babile, Ina and Angaredebou as the core testing sites of the three mega-environments for testing the Regional Uniform Variety Trials-extra-early.

Impacts of climate change and alternative adaptation options on winter wheat yield and water productivity in a dry climate in Central Europe

Abstract: The main objective of the present crop simulation study was to determine the impact of climate change on the winter wheat production of a dry area situated in north-east Austria (Marchfeld region) based on the CERES-Wheat crop-growth simulation model associated with global circulation models (GCMs). The effects of some of the feasible regional- and farm-based adaptation measures (management options) on crop yield and water and nitrogen (N) balance under the climate scenarios were simulated. Climate scenarios were defined based on the ECHAM5, HadCM3 and NCAR PCM GCM simulations for future conditions (2021–50) as described in the Special Report on Emission Scenarios A1B (Nakicenovic & Swart 2000). The potential development, yield, water demand and soil N leaching were estimated for winter wheat and all of the defined climates (including rising CO2 levels) and management scenarios (soil cultivation, windbreaks and irrigation). The results showed that a warming of 2°C in the air temperature would shorten the crop-growing period by up to 20 days and would decrease the potential winter wheat yield on nearly all of the soil types in the region. Particularly, high-yield reductions were projected for light-textured soils such as Parachernozems. A change from ploughing to minimum tillage within the future scenario would lead to an increase of up to 8% of the mean yield of winter wheat. This effect mainly resulted from improved water supply to the crop, associated with higher soil water storage capacity and decrease of unproductive water losses. Hedgerows, which reduce the wind speed, were predicted to have particularly positive effects on medium and moderately fine-textured soils such as Chernozems and Fluvisols. With both management changes, regional mean-yield level can be expected to be +4% in comparison with no management changes in the future conditions. Compared with the baseline period, water demand for the potential yield of winter wheat would require 6–37 mm more water per crop season (area-weighted average). The highest water demand would be on medium-textured soils, which make up the largest amount of area in the study region. Additionally, the effects of snow accumulation near hedgerows would further increase the yield, but would also lead to higher N leaching rates. However, specific management options, such as minimum tillage and hedgerows, could contribute towards reducing the increasing water demand.

Sensitivity of barley varieties to weather in Finland.

Abstract: Global climate change is predicted to shift seasonal temperature and precipitation patterns. An increasing frequency of extreme weather events such as heat waves and prolonged droughts is predicted, but there are high levels of uncertainty about the nature of local changes. Crop adaptation will be important in reducing potential damage to agriculture. Crop diversity may enhance resilience to climate variability and changes that are difficult to predict. Therefore, there has to be sufficient diversity within the set of available cultivars in response to weather parameters critical for yield formation. To determine the scale of such ‘weather response diversity’ within barley (Hordeum vulgare L.), an important crop in northern conditions, the yield responses of a wide range of modern and historical varieties were analysed according to a well-defined set of critical agro-meteorological variables. The Finnish long-term dataset of MTT Official Variety Trials was used together with historical weather records of the Finnish Meteorological Institute. The foci of the analysis were firstly to describe the general response of barley to different weather conditions and secondly to reveal the diversity among varieties in the sensitivity to each weather variable. It was established that barley yields were frequently reduced by drought or excessive rain early in the season, by high temperatures at around heading, and by accelerated temperature sum accumulation rates during periods 2 weeks before heading and between heading and yellow ripeness. Low temperatures early in the season increased yields, but frost during the first 4 weeks after sowing had no effect. After canopy establishment, higher precipitation on average resulted in higher yields. In a cultivar-specific analysis, it was found that there were differences in responses to all but three of the studied climatic variables: waterlogging and drought early in the season and temperature sum accumulation rate before heading. The results suggest that low temperatures early in the season, delayed sowing, rain 3–7 weeks after sowing, a temperature change 3–4 weeks after sowing, a high temperature sum accumulation rate from heading to yellow ripeness and high temperatures (⩾25°C) at around heading could mostly be addressed by exploiting the traits found in the range of varieties included in the present study. However, new technology and novel genetic material are needed to enable crops to withstand periods of excessive rain or drought early in the season and to enhance performance under increased temperature sum accumulation rates prior to heading.

Effects of Some Heavy Metals on Seed Germination Characteristics of Canola (Barassica napus), Wheat (Triticum aestivum) and Safflower (Carthamus tinctorious) to Evaluate Phytoremediation Potential of These Crops

Abstract: Heavy metal pollutants are the main concern of new agricultural productions. Industrial products and using synthetic materials leads to drastically increase in concentration of different heavy metals in the environment. Lead and Cadmium are two famous heavy metals which are largely used in electronic industries thus the waste water of factories could pollute agricultural lands. Different heavy metal solutions were investigated for their effects on seed germination characteristics and phytoremediation potential of two oil crops ( canola, Brassica napusandsafflower, Carthamustinctorious) and a cereal crop (wheat, Triticumaestivum). The Canola, Safflower and Wheat seeds were germinated after treatments in solutions containing varying concentrations of heavy metals. Five different concentrations of heavy metals including (BiNO3, BiNO3, CdNO3, Sr (NO3)2, ZnNO3) at 50, 200, 350, 500, 1000 ppm and distilled water considered as control treatment. Results showed that in all treatments the percentage of seed germination, root and shoot length decreased as concentrations of solution increased. No germination was observed at 1000 ppm of cadmium level. Root and seedling vigor increased by application of 200 ppm of BiNO3. There were no seedling growth at 350 and 500 ppm of cadmium and lead concentration.

Implications of farmers’ seed exchanges for on-farm conservation of quinoa, as revealed by its genetic diversity in Chile

Abstract: Quinoa cultivation in Chile presents an ancient and active complex of geographic, climatic, social and cultural interactions that has determined its current biodiversity in the three main growing zones (north, central and south). Importantly, these interactions involve the participation of farmers, whose activities are at the base of seed exchange networks due to their knowledge and in situ conservation of genetic diversity. The present study reports how a better understanding of farmers' seed exchanges and local production practices could impact the genetic structure and diversity of quinoa at national scale in Chile. Using field interviews and characterization of 20 microsatellite genetic markers in a multi-origin set of 34 quinoa accessions representative of Chile and the South American region, the phenetic analysis of germplasm was consistent with the current classification of quinoa ecotypes present in Chile and Andean zone. This allowed the identification of five populations, which were represented by quinoa of Salares (northern Chile), Coastal/Lowlands (central and southern Chile), Highlands (Peru, Bolivia and Argentina) and Inter-Andean Valleys (Ecuador and Colombia). The highly informative quality of the markers used revealed a wide genetic diversity among main growing areas in Chile, which correlated well with natural geographical-edaphic-climatic and social-linguistic context to the expansion of quinoa biodiversity. Additionally, in addition to ancient seed exchanges, this process is still governed by the diverse agricultural practices of Andean farmers. Genetic erosion is considered an imminent risk due to small-scale farming, where the influence of increased migration of people to urban systems and export-driven changes to the agro-ecosystems may further reduce the diversity of quinoa plants in cultivation. (Resume d'auteur)

Effect of Intercropping and Crop Arrangement on Yield and Productivity of Late Season Maize/soybean Mixtures in the Humid Environment of South Southern Nigeria

Abstract: Field experiments were carried out between September and December in 2007 and 2008 at Akamkpa (150 15'' N; 80 22'' E), Nigeria. The objective was to investigate yield and productivity of maize and soybean as sole crops and as additive mixtures (100:100) in response to five levels of nitrogen (0, 25, 50, 75 and 100 kg/ha) and five crop arrangements (sole maize at 53,333 plants/ha, sole soybean at 266,666 plants/ha and maize: soybean intercrop arrangements of 1:1, 2:2 and 1:2). The trial was a split-plot design in a randomized complete block with nitrogen in main plot and crop arrangement in sub-plot, with three replications. Intercropping had no significant effect on grain yield of maize in 2007. In 2008, maize grain yield grain yield reduction in mixture was 6 percent compared to sole cropping. Soybean seed yield reduction in mixture was 32 and 43 percents in 2007 and 2008, respectively. Crop arrangement significantly influenced yield components and yield in both maize and soybean. Planting maize and soybean in 1:1, 2:2 or 1:2 arrangement had no significant effect on maize in 2007 but depressed grain yield of maize by 38, 35 and 14 percents in 2008. Spatial arrangement of maize and soybean in 1:1, 2:2, and 1:2 depressed soybean yield by 51, 44 and 45 percents in 2007 and by 86, 64 and 73 percents in 2008. Intercropping reduced the relative maize grain yield by only 1 percent in 2007 and from 4 to 9 percents in 2008. Soybean relative yields were from 31 to 34 percent lower than sole crop yield in 2007 and 39 to 46 percent lower in 2008. The relative yield totals for both 2007 and 2008 were well above unity, an indication that the system was highly productive. This implies that intercrops were 64, 66 and 63 percents in 2007 and 43, 57 and 65 percents in 2008, more productive than the sole crops at 2:2, 1:2 and 1:1 arrangements, respectively. Late season maize and soybean may be planted in 2:2 or 1:2 arrangements to take advantage of optimum soybean seed yield and 65-100 percents of the maize grain yield in the humid South Southern Nigeria.

Climate Change and Agricultural Production in South Africa: Impacts and Adaptation options

Abstract: The primary aim of the paper was to identify the impacts and adaptation options of climate variability and change on agricultural production in Limpopo province. The following objectives were identified: to understand the impacts of climate variability and change on agricultural production in Limpopo province ; to assess the impacts of climate variability and change on agricultural production in Limpopo province and to identify adaptation measures that reduces the impacts of climate variability and change on agricultural production in Limpopo province. A representative sample of 300 farmers aged 16 – 65+ years (46 percent males and 54 percent females) participated in the study. The study involved Sekhukhune and Capricorn districts, with 56 percent farmers in Capricorn and 44 percent in Sekhukhune district. The following 11 local municipalities were visited: Elias Motsoaledi, Makhuduthamaga, Fetakgomo, Ephraim Mogale, Tubatse, Lepelle Nkumpi, Blouberg, Aganang, Polokwane, and Molemole. Statistics was used to determine climate variability and change impact on agricultural production. Results indicate that farmers are aware that Limpopo province is getting warmer and drier with increased frequency of droughts, changes in the timing of rains, observed trends of temperature and precipitation. This paper also confirmed that being full time farmer, gender, information on climate change, information received through extension services and adaptation to climate change are some of the important determinants of agricultural production, food scarcity and unemployment. The paper also presented perceived adaptation strategies of selected Limpopo province farmers. Some of their perceived adaptation strategies included: (a) soil management strategies, (b) water management strategies and (c) others like use of subsidies and use of insurance. Other important adaptation options being used by farmers were also discussed in this paper including different adaptation measures against colds, heat, frost, abnormal wind, hail, lack of extension support, nematodes, insecticides, worms, temperature and rainfall. The results of this paper are potentially valuable to the agricultural sector considering the threates that climate change poses across climate sensitive sectors

Climate change and land suitability for potato production in England and Wales: impacts and adaptation

Abstract: The viability of commercial potato production is influenced by spatial and temporal variability in soils and agroclimate, and the availability of water resources where supplementary irrigation is required. Soil characteristics and agroclimatic conditions greatly influence the cultivar choice, agronomic husbandry practices and the economics of production. Using the latest (UKCP09) scenarios of climate change for the UK, the present paper describes a methodology using pedo-climatic functions and a geographical information system (GIS) to model and map current and future land suitability for potato production in England and Wales. The outputs identify regions where rainfed production is likely to become limiting and where future irrigated production would be constrained due to shortages in water availability. The results suggest that by the 2050s, the area of land that is currently well or moderately suited for rainfed production would decline by 88 and 74%, respectively, under the ‘most likely’ climate projections for the low emissions scenario and by 95 and 86%, respectively, for the high emissions scenario, owing to increased likelihood of dry conditions. In many areas, rainfed production would become increasingly risky. However, with supplementary irrigation, c. 0·85 of the total arable land in central and eastern England would remain suitable for production, although most of this is in catchments where water resources are already over-licensed and/or over-abstracted; the expansion of irrigated cropping is thus likely to be constrained by water availability. The increase in the volume of water required due to the switch from rainfed- to irrigated-potato cropping is likely to be much greater than the incremental increase in water demand solely on irrigated potatoes. The implications of climate change on the potato industry, the adaptation options and responses available, and the uncertainty associated with the land suitability projections, are discussed.

Effect of wheat dwarfing genes on nitrogen-use efficiency

Abstract: Near isogenic lines (NILs) varying for alleles for reduced height (Rht) and photoperiod insensitivity (Ppd-D1a) in a cvar Mercia background (rht (tall), Rht-B1b, Rht-D1b, Rht-B1c, Rht8c+Ppd-D1a, Rht-D1c, Rht12) were compared at a field site in Berkshire, UK, but within different systems (‘organic’, O, in 2005/06, 2006/07 and 2007/08 growing seasons v. ‘conventional’, C, in 2005/06, 2006/07, 2007/08 and 2008/09). In 2007 and 2008, further NILs (rht (tall), Rht-B1b, Rht-D1b, Rht-B1c, Rht-B1b+Rht-D1b, Rht-D1b+Rht-B1c) in both Maris Huntsman and Maris Widgeon backgrounds were added. The contrasting systems allowed NILs to be tested in diverse rotational and agronomic, but commercially relevant, contexts, particularly with regard to the assumed temporal distribution of nitrogen availability, and competition from weeds. For grain, nitrogen-use efficiency (NUE; grain dry matter (DM) yield/available N; where available N=fertilizer N+soil mineral N), recovery of N in the grain (grain N yield/available N), N utilization efficiency to produce grain (NUtEg; grain DM yield/above-ground crop N yield), N harvest index (grain N yield/above-ground crop N yield) and dry matter harvest index (DMHI; grain DM yield/above-ground crop DM yield) all peaked at final crop heights of 800–950 mm. Maximum NUE occurred at greater crop heights in the organic system than in the conventional system, such that even adding just a semi-dwarfing allele (Rht-D1b) to the shortest background, Mercia, reduced NUE in the organic system. The mechanism of dwarfing (gibberellin sensitive or insensitive) made little difference to the relationship between NUE and its components with crop height. For above-ground biomass: dwarfing alleles had a greater effect on DM accumulation compared with N accumulation such that all dwarfing alleles could reduce nitrogen utilization efficiency (NUtE; crop DM yield/crop N yield). This was particularly evident at anthesis in the conventional system when there was no significant penalty for severe dwarfism for N accumulation, despite a 3-tonne (t)/ha reduction in biomass compared to the tallest lines. Differences between genotypes for recovery of N in the grain were thus mostly a function of net N uptake after anthesis rather than of remobilized N. This effect was compounded as dwarfing, except when coupled with Ppd-D1a, was associated with delayed anthesis. In the organic experiments there was greater reliance on N accumulated before anthesis, and genotype effects on NUE were confounded with effects on N accumulated by weeds, which was negatively associated with crop height. Optimum height for maximizing wheat NUE and its components, as manipulated by Rht alleles, thus depend on growing system, and crop utilization (i.e. biomass or grain production).

Characterisation of Several Rye Cultivars with Respect to Arabinoxylans and Extract Viscosity

Abstract: Arabinoxylans are considered as the major limiting factor for use of rye in animal feeding. In this study, four selected winter rye cultivars were grown at nine locations and tested for arabinoxylans including total (TAX), soluble (SAX) and insoluble fractions (IAX), extract viscosity, falling numbers and crude protein contents. Amounts of TAX ranged on average between 89 and 103 g/kg wholemeal flour, and the extract viscosity between 2.6 and 5.1 cSt. The extract viscosity was significantly correlated with falling numbers and all three arabinoxylan fractions. Arabinoxylan contents and extract viscosity were influenced by the rye genotype. The anthocyanin free hybrid cultivar Helltop combined reduced TAX, SAX and IAX levels with low extract viscosity and high crude protein contents and seems to be more suitable for use in animal feeding than the other three cultivars tested in this respect.

Coffee Quality and Its Interactions with Environmental Factors in Minas Gerais, Brazil

Abstract: The aim of this work was to assess the geographic distribution of coffee quality in Minas Gerais state, Brazil, and to study its interactions with chemical and environmental factors. Correlations between environmental factors, chemical compounds and sensory quality of participants of the Minas Coffee Quality Contest were made through Principal Component Analysis and Biplot Graphics. The results showed discriminations of high and low scores as a result of environmental variables, demonstrating a strong influence of temperature, rainfall, altitude and latitude on the quality of the coffees studied. In addition to the environmental characteristics, the chemical compounds trigonelline, caffeine, and especially the acid-5-cafeiolquinic were also relevant in discriminating the scores obtained through sensory analysis. This work is an initial indication of the factors that determine the quality of coffees produced in Minas Gerais.

Chemical Composition, Antibacterial and Antioxidant Activities of Leaves Essential Oils from Syzygium cumini L., Cupressus sempervirens L. and Lantana camara L. from Egypt

Abstract: Leaves essential oils of Syzygium cumini L. Cupressus sempervirens L. and Lantana camara L., from Alexandria, Egypt were analysed by Gas chromatography-mass spectrometry (GC-MS). The antibacterial and antioxidant activities were assessed for each oil using minimum inhibitory concentrations (MICs) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods; respectively. The main oil constitutes were alpha-pinene (17.53%), alpha-terpineol (16.67%) and alloocimene (13.55%) in S. cumini, trans-caryophyllene (15.57%) and alpha-humulene (9.16%) in L. camara and cedrol (21.29%), delta3-carene (17.85%) and alpha-pinene (6.9%) in C. Sempervirens. The antibacterial activity was studied against some bacterial strains. The oil of S. cumini demonstrated strong inhibition activity against the tested bacterial strains. The total antioxidant activity (TAA %) was 11.13, 9.13, 3.13% for S. cumini, L. camara and C. sempervirens, respectively. Our work revealed that the studied leaf oils are new promising potential sources of antioxidants and antibacterial compounds and good future practical applications for human and plant health.

Phenolic Compounds and Antioxidant Activity from Saffron (Crocus sativus L.) Petal

Abstract: Saffron petal is the main by-product of saffron processing which is producing in large amounts annually. The purposes of this work were to determine total phenolics content in the methanolic extract of saffron petal using Folin-ciocalteu reagent and to measure their antioxidant activity in various in vitro models, such as ?-carotene-linoleate and 1,1-diphenyl-2-picryl hydrazyl (DPPH). Saffron petal extract in different concentrations (0.5-5 mg ml-1) were compared with standard antioxidants of ascorbic acid, ?-tocopherol and TBHQ (0.5-1 mg ml-1). Total phenolics content was 3.42 mg gallic acid/g dry weight. In model systems of beta-carotene-linoleate and DPPH, the extract at 500 ppm concentration showed 91.4% and 74.2% antioxidant activity which was comparable with that of TBHQ (93.1% and 77.9%) at 100 ppm. The results showed that saffron petal could be considered as a bioresource of phenolic compounds with high antioxidant activity.

Application of Nitrogen and Silicon Rates on Morphological and Chemical Lodging Related Characteristics in Rice (Oryza sativa L.) at North of Iran

Abstract: Rice-based irrigated lowlands are the major cropping system in north of Iran. This experiment was carried out in split plot in basis of randomized complete block design with three replications at north of Iran in 2010. Main plot was nitrogen rates including (0, 50, 100 and 150 kg N ha -1 ) applied as urea and sub plot was silicon rates (0, 300 and 600 kg ha -1 ) applied as calcium silicate. Results showed that minimum of the plant height, flag leaf length, fourth inter-node bending moment and grain yield (4350 kg ha -1 ) were obtained at N 0 , as well as the maximum of the plant height, panicle length, flag leaf length, third inter-node length were observed at N 100 and N 150 , respectively. But the highest of bending moment obtained for fourth inter-node and maximum grain yield (6063 kg ha -1 ) was observed in N 150 . Treatment Si 600 had increased significantly over control in plant height, stem length, panicle length, third inter-node length, third inter-node bending moment, cellulose, hemi-cellulose and lignin in relation to 7.76, 9.91, 30.18, 31.03, 18.71, 7.60, 34.50 and 26.26 %, respectively. Therefore treatment with N 150 and Si 600 had shown best results for agronomical indices and grain yield.

Influence of Drought Stress on Oxidative Damage and Antioxidant Defense Systems in Tolerant and Susceptible Wheat Genotypes

Abstract: Drought is one of the major factors limiting crop production in arid and semi-arid regions. Twenty wheat genotypes with wide range of sensitivity to drought, including 18 varieties of bread wheat (Triticum aestivum L.) and two varieties of durum wheat (Triticum turgidum L.) were used in two separate field experiments in 2009-2010 at the Experimental Station of College of Agriculture in Shiraz University. Each experiment was conducted as a randomized completed block design with three replications. The moisture level in one of the experiments was optimum (100% field capacity) while the second experiment was conducted under drought stress (45% field capacity). Several biochemical components including enzymatic (catalase, CAT; peroxidase, POD; superoxide dismutase, SOD and ascorbate peroxidase, APX) and non-enzymatic (proline and carotenoids, Car) antioxidant defense systems and some factors of oxidative damage (hydrogen peroxide, H2O2; lipid peroxidation, LPO and membrane stability index, MSI) were analyzed in the two conditions. Drought stress caused significant increase in enzymatic antioxidant activities, proline content, H2O2 and LPO content at the flowering stage, while Car content and MSI decreased significantly in all genotypes. Drought tolerant genotypes showed the highest enzymatic and non-enzymatic antioxidants, highest MSI and the lowest LPO and H2O2. This trend was reversed in susceptible genotypes. The enzymatic antioxidants had higher correlation than non-enzymatic with oxidative stress factors and yield stability index (YSI). POD showed the highest positive correlation with MSI and the highest negative correlation with LPO. H2O2 and MSI showed the highest correlation with YSI. In present study, Kavir and Alamut varieties were selected respectively as the most tolerant and susceptible genotypes.

Bioaccumulation of heavy metals in fish (hydrocynus forskahlii, hyperopisus bebe occidentalis and clarias gariepinus) organs in downstream ogun coastal water, nigeria

Abstract: In this study accumulation of some heavy metals Cadmium (Cd), Chromium (Cr), Cobalt (Co), Nickel (Ni) and Lead (Pb) in the operculum, gills, heart, kidney, muscle and vertebrae were determined in some fishes (Hydrocynus forskahlii, Hyperopisus bebe occidentalis and Clarias gariepinus) collected from fishermen around Ogun estuary. The accumulation of the metals in different organs showed significant differences (P H. bebe occidentalis > C. gariepinus and the pattern of distribution was Ni > Cr > Co > Cd > Pb for all the fish species. The levels of Ni and Cr in this study were higher than the maximum permissible limits (FAO, UNEP, FEPA and WHO) for human consumption and that of Cd, Pb and Co were still lower. Safe disposals of domestic sewage and industrial effluents as well as enforcement of laws enacted to protect our environment are therefore advocated.

Effect of Planting Density on Root Lodging Resistance and Its Relationship to Nodal Root Growth Characteristics in Maize (Zea mays L.)

Abstract: Increase of planting density has been widely used to increase grain yield in maize. However, it may lead to higher risk of root lodging hence causing significant yield loss of the crop. The objective of this study was to investigate the effect of planting density on maize nodal root growth characteristics and to analyse their relationships to root lodging resistance. Field experiment was conducted in 2010 and 2011, using two maize varieties, Zhengdan 958 (ZD) and Xianyu 335 (XY), under three planting densities, viz., 4.50, 8.25 and 12.00 plants m -2 . The results showed the root failure moment, an indicator of root lodging resistance, was significantly affected by the planting density, the maize variety, as well as the crop developmental stages, and was decreased with increasing planting density. The number and the average diameter of the roots on the upper internodes (phytomer 5 to 8) were decreased with increasing planting density, whereas the maize variety had little effects on those variables. On the contrary, the root angle was less responsive to planting density but was significantly affected by the variety being that XY had larger root angle than did ZD. The root failure moment was linearly positively correlated with the total root number and the average root diameter on the upper internodes, indicating that a greater root number and a larger root diameter are important traits for enhancing root lodging resistance in maize plants.

Effects of Emulsifier and Multi-enzyme in Different Energy Densitydiet on Growth Performance, Blood Profiles, and Relative Organ Weight in Broiler Chickens

Abstract: This study was conducted to determine the effects of emulsifierand multi-enzyme in different energy density diet on growth performance, blood profiles, and relative organ weight in broiler chickens. A total of five hundred and forty2-d-oldmale Ross broilers (BW of 42.4 ±1.3 g) wereused in a 35-d experiment and randomly divided into 5 treatment groups: 1) NC [low energy diet, 3% tallow, ME = 3000 (1 to 21 d) and 3100 kcal/kg (22 to 35 d)], 2) PC [high energy diet, 5.5% soybean oil, ME = 3150 (1 to 21 d) and 3250 kcal/kg (22 to 35 d))], 3) P1 (NC+0.1% multi-enzyme), 4) P2 (NC + 0.05% emulsifier), 5) P3 (NC + 0.1% multi-enzyme + 0.05% emulsifier). Multi-enzymecontained ?-galactosidase, galactomannase, xylanase, and beta-glucanase. Emulsifier was a commercial product named Prosol® which wassodium stearoyl-2-lactylate.There were 9 replications per treatment with 12 birds per pen. From d 0 to 21, body weight gain (BWG) in PC and P1 treatments increased (P < 0.05) compared with NC treatment. From d 22 to 35, feed intake (FI) was greater (P < 0.05) in P3 treatment than PC treatment. On d 35, triglyceride concentration in PC, P1 and P3 treatments was greater (P < 0.05) compared with NC treatment. No differences were observed on white blood cell (WBC), red blood cell (RBC) and glucose concentration. The relative weight of the spleen was significantly decreased (P < 0.05) in P3 treatment compared with PC treatment. Furthermore, the relative weight of the bursa of Fabricius in P3 treatment was higher (P < 0.05) than PC, P1 and P2 treatments. In conclusion, the results of this study indicate that emulsifier andmulti-enzymein low-density diets can partially improve growth performance, triglyceride, and relative organ weight in broiler chickens, which can counterpart the negative effects caused by the decreased nutrient concentration.

Evaluating of Drought Stress Tolerance Based on Selection Indices in Spring Canola Cultivars (Brassica napus L.)

Abstract: In order to study the response of nine cultivars spring canola (Brassica napus L.) to drought stress, an experiment was conducted in a factorial experimental on the basis of randomized complete block design with three replications under two irrigated conditions during 2009-2010 cropping season. Eleven drought tolerance indices including stress tolerance index (STI), stress susceptibility index (SSI), tolerance index (TOL), geometric mean production (GMP), mean production (MP), yield index (YI), yield stability index (YSI), drought resistance index (DI), modified stress tolerance (MSTI), relative drought index (RDI) and stress susceptibility percentage index (SSPI) were calculated based on grain yield under drought (Ys) and irrigated conditions (Yp).Yield in stress (Ys) and non-stress (Yp) conditions were significantly and positively correlated with STI, GMP, MP, YI, TOL, DI, RDI, YSI, SSPI, K1STI and K2STI and negatively correlated with SSI. Results of this study show thatthese indices of stress tolerance/resistance such as K1STI, K2STI, SSPI, RDI and DI can be used as the most suitable indicators for screening drought tolerant cultivars.Screening drought tolerantcultivars using ranking method discriminated cultivars Hyola 308, Heros and SW5001 as the most droughts tolerant. Cluster analysis classified the cultivars into three groups i.e., resistant, susceptible and tolerant to drought conditions. Therefore they are recommended to be used as parents for improvement of drought tolerance in other cultivars.

The Effect of Biochar on the Growth and N Fertilizer Requirement of Maize (Zea mays L.) in Green House Experiment

Abstract: Greenhouse experiments were carried out to study the effect of biochar and other organic amendment (Chicken Manure, CM; and City waste compost, CW) using on the growth and N fertilizer requirement of maize. The first experiment was carried out to study the effect of biochar application to maize growth, and then continued to study the residual effect of biochar. The second experiment was carried out to study the effect of biochar application on nitrogen fertilizer requirement. The results show that the first season of maize biomass of organic amendment of treated soils did not significantly different from no organic amendment. However, organic amendment improved soil fertility status, especially increasing C-organic, N, K and CEC. The biomass of the second season maize of biochar of treated soil was higher compared to the other treatments. The second experiment shows that biochar application decreased N fertilizer requirement. To produce 3.23 Mg ha -1 biomass, it required 90 kg ha -1 N for 15 Mg ha -1 CM biochar treated soil, and 160 kg ha -1 for the non treated soil.

Removal of Organophosphorus (OP) Pesticide Residues from Vegetables Using Washing Solutions and Boiling

Abstract: In a monitoring study, the effects of household processing on removal of organophosphate residues (malathion, fenitrothion, formothion, parathion, methyl parathion and chlorpyriphos) in tomato, bean, okra, eggplant, cauliflower and capsicum were studied. The processes included washing separately with (water, 0.9 % NaCl, 0.1 % NaHCO3, and 0.1 % acetic acid, 0.001 % KMnO4, 0.1 % ascorbic acid, 0.1 % malic acid and 0.1 % oxalic acid and 2 % aqueous solution of raw Spondias pinnata (SP)) and boiling. Organophosphorous (OP) residues were estimated (for real market samples and spiked samples) using multi residue analytical technique employing with capillary gas chromatograph with mass spectrometry detector (GCMSD). In all of the vegetables, washing with different household chemicals reduced the residues by 20-89 % and boiling reduced the residues by 52-100 %. Boiling of vegetables was found to be more effective than washing in dislodging the residues.

Drivers of Use of Information and Communication Technologies by Farm Households: The Case of Smallholder Farmers in Kenya

Abstract: Smallholder farmers’ access to markets has traditionally been constrained by lack of market information. The desire to strengthen farmer access to market has seen the emergence of a number of projects that employ ICT tools in the provision of market information. This study assesses the conditioners of the use of ICT tools in general and mobile phones in particular by smallholder farmers for agricultural transactions. The study finds that several farmer, farm and capital endowment factors affect the use of ICT tools and mobile phones. Specifically, age, occupation, nearness to output market, number of crop enterprises, farming experience literacy and crop income explain the use of tools while gender, nearness to output market, household size, owning a phone, level of literacy, crop income and value of assets explain the intensity of use of the mobile for agricultural transaction purposes. It discusses the implications of these findings for policy.

Impact of Flavonoids against Woolly Apple Aphid, Eriosoma lanigerum (Hausmann) and Its Sole Parasitoid, Aphelinus mali (Hald.)

Abstract: Cut-shoot bioassay test was used to study the significance of three flavonoids as aphicides against the woolly apple aphid (WAA), Eriosoma lanigerum (Hausmann). The used flavonoids were two flavanols that are quercetin dehydrate and rutin hydrate, but rutin hydrate is a glycoside of quercetin dehydrate. In addition to one flavanone that was naringine. These flavonoids were used at three concentrations; 100 ppm, 1000 ppm and 10,000 ppm. Results showed that the three tested flavonoids were active as aphicides against the target species and that mortality to nymphs was higher than that obtained against apterous adults. Increasing the concentration of the flavonoids resulted in a remarkable increase in nymphs mortality. However, rutin hydrate is more toxic to WAA than quercetin dehydrate and naringin. The three flavonoids had slight effect on the sole parasitoid of WAA, Aphelinus mali compared with effect caused by imodacloprid insecticide. Quercetin dehydrate, rutin hydrate and naringine can be used as botanical insecticides and incorporated into integrated management programs of the aphid.

Comparison and Improvement of Different Methods of RNA Isolation from Strawberry (Fragria * ananassa)

Abstract: Isolation of high-quality RNA from different strawberry tissues is often affected by the presence of high levels of contamination by polysaccharides and phenolic compounds. By the methods of improved CTAB, SDS, and guanidinium thiocyanate, total RNA was isolated from leaves of strawberry. The result indicated that total RNA is of high quality and undegraded by using CTAB. However, it was difficult to isolate total RNA from leaves of strawberry by using guanidinium thiocyanate, and total RNA could be extracted by using SDS with low concentration, impurity and degradation in some degree. After comparing, an improved 3% CTAB3 was used to isolate RNA from tissues of strawberry, and the isolated RNA was good enough for further applications. After RT-PCR, the 699 bp sequence of glucose-6-phosphate dehydrogenase (G6PDH) gene was obtained to identify the quality of total RNA from strawberry. In this experiment, improved 3% CTAB3 method could be regarded as a simple, rapid, economic and convenient method for the RNA isolated from strawberry.