Agriculture

A field experiment was carried out at the experimental Station of National Research Centre – El-Nubarya district, El-Behera Governorate, Egypt during two seasons of 2010/2011 and 2011/2012 to study the effect of drought stress (2504, 2003 and 1502 m3/fed/Season) (100 % IR, 80 % IR and 60 % IR) and four foliar application levels of ascorbic acid (AA) (0.0, 100, 200 and 300 mg/L) and their interaction on yield, irrigations water use efficiency of wheat, protein content and protein yield under newly reclaimed sandy soil conditions Results indicated that water irrigation requirement varied significantly in all studied characters. The water irrigation requirement of (80 % IR) produced high grain yield per faddan and insignificantly outyielded the water irrigation requirements of (100 % IR). Increasing foliar application levels of ascorbic acid significantly increased grain and straw yields per plant and per faddan as well as protein content, protein yield, plant height, spike length, seed index, number of spikelet’s per spike and water use efficiency. Results indicated that the interaction between water irrigation requirements and foliar application levels of ascorbic acid had significant effect on all studied characters. The interaction between the water irrigation requirements of (80% IR) and (300 mg/L) foliar application level of ascorbic acid gave the highest values of grain, straw and protein yields per faddan, water use efficiency and significantly outyielded the other all interactions. This means that we can save 20 % of irrigation water by using 80 % IR to irrigate the new lands under the conditions of this trail.

Flood discharge is one of important factors in designs and hydrological works. Because of non-facilities and non-hydrometric equipment in basins without statistics or with deficient statistics especially in small watersheds, estimation of maximum instantaneous flood discharge is one of main problems in watershed projects. In this stud with the aim of determination of acceptable method to estimate maximum instantaneous flood discharge in small watersheds, two methods one base to basin area and other based to physiographical feature and precipitation were studied. The results showed that among methods related to basin area, Horton method with residual sum of squares 2.8(RMSE=2.8) and among methods related to basin- physiographical feature and precipitation, curve number with RMSE=20.6 had least error .so, determined as the best methods. FHWA method because of having most amount of RMSE=5924.5 had the least efficiency for determination of peak discharge in this area.

The effect of drying behavior on drying rate and quality characteristics of potato slices in a vacuum- infrared drying system was studied. In this work, the effect of the infrared radiation powers (100, 150 and 200 W) and vacuum levels (20, 80, 140 mm [Hg] and atmosphere pressure) at different thickness (1, 2 and 3 mm) on drying rate, shrinkage percentage and rehydration capacity were investigated. From the study, it was concluded that IR power level has significant effects to processing time and drying rate.The processing time reduced,while drying rates were higher with increased in IR power. Drying rate curve of potato slices at initially time of drying because of surface moisture evaporation in the ascending phase and afterward due to the start of influence of water from within of material to surface descending phase occurs. Also shrinkage percentage increased with increase of sample thickness. In other words, shrinkage was decreased at different thickness with increase of infrared radiation power and vacuum level. It was found that the long period of drying and increase of sample thickness may have contributed to a decrease in rehydration capacity. However, rehydration capacity at temperature 100°C for 3 min was more than temperature 25°C in duration 12 min.

Patterns of crop diversification of modern agricultural technology, especially during the period of the Green Revolution in the late sixties and early seventies, there is a continuous surge for diversified agriculture in terms of crops, primarily on economic considerations. Indian agriculture is increasingly getting influenced more and more by economic factors. This need not be surprising because irrigation expansion, infrastructure development, penetration of rural markets, development and spread of short duration and drought resistant crop technologies have all contributed to minimizing the role of non- economic factors in crop choice of even small farmers. What is liberalization and globalization policies are also going to further strengthen the role of price related economic incentives in determining crop composition both at the micro and macro levels. Obviously, such a changing economic environment will also ensure that government price and trade policies will become still more powerful instruments for directing area allocation decisions of farmers, aligning thereby the crop pattern changes in line with the changing demand-supply conditions. In a condition where agricultural growth results more from productivity improvement than from area expansion, the increasing role that price related economic incentives play in crop choice can also pave the way for the next stage of agricultural evolution where growth originates more and more from value- added productions.

Kashan playa, Located in the west of Central Desert of Iran, has been subjected to severe desertification problems. Most of these problems are due to human activities, overgrazing, sand dune mobility, soil salinity and ground water depletion. Monitoring desertification, land degradation and land cover requires rapid and accurate procedures. Remotely sensed satellite technology allows land degradation processes to be monitored over time. Two Landsat TM/ETM+ satellite images for 12 years period (1990-2002) with field observations were provided basic information for mapping of the extend and monitoring of the Kashan playa in central desert of Iran. Several change detection techniques such as image differencing, vegetation change analysis, principal component analysis and classification comparison have been applied to the data. Maximum Likelihood classification analysis showed a kappa coefficient accuracy of 86% and 82% for the TM and ETM+ images. Results revealed that about 35 % of the study area mostly salty lands and fixed sand dune has been rapidly changed. The overall rate changes of the desert lands and vegetation are about 7275 and 62 ha year^-1 respectively.

Tree height-diameter relationship can be used as an important input component in forest growth and yield models and description of stand dynamics. Five non-linear growth functions were fitted to tree height-diameter data of 21 years old Gmelina arborea plantation in Ibadan, South west Nigeria. The data consisted of three sets: 2004, 2008 and 2011 on total tree height and diameter at breast height (dbh). According to the model statistics, the five growth functions fitted the data equally well, but resulted in different asymptote estimates. Modified exponential fit was observed to give the best fit for the three data sets based on least square error, coefficient of determination and significance. The models are: Ht = (R2 = 36.21%), Ht = (R2 = 37.53%) and Ht = (R2 = 34.74%) for 2004, 2008 and 2011 data sets. The predicted values follow the same nonlinear pattern and formed close to the line of best fit without much outlier. The result of this study revealed that the ability of dbh in determining height is not strong enough based on the model’s goodness of fit and the model’s ability for predictive purposes. Hence, more variables such as age, crown area and soil fertility were recommended to be incorporated in future prediction of the tree height in the study area. Also, the potential tree height-diameter equations should be evaluated and validated for their predictive capabilities across a range of tree diameters. This useful information can help forest researchers and managers to select and apply the appropriate models.

The experiment was conducted in the Desert Guide Way Farm which belongs to the Agricultural Extension Department / Agricultural Office in Karbala Governors to investigate operating of pumping unit of drip irrigation system by using multi-power sources. Multi- power Sources with three levels including: pump with motor operated with charged battery by solar and wind power, pump with motor operated with internal combustion engine by bio fuel , pump with motor operated with internal combustion engine by natural fuel (gasoline) which represent main plot and discharge levels including 3.5 let. h^(-1) and 1.8 let.h^(-1) which represent sub plot were used in this study. Water horse power, break horse power, pumping efficiency, operating cost, were studied in this experiment. Randomized complete block design ( RCBD ) with three replications was studied in this experiment.The results showed that pump with motor operated with internal combustion engine by natural fuel (gasoline) treatment got higher brake horse power reached 0.238 hp mean while pump with motor operated with charged battery by solar and wind power treatment managed to have less operating costs reached 0.71 $/day also the results showed that discharge 3.5 let ?ha?^(-1)tertment mange to have highest water horse power reached 0.203 hp and brake horse power 0.289 hp and highest pumping efficiency stood 70.28% and least operating cost stood 2.74 $/day. The interaction between the pump with motor operated with charged battery by solar and wind power with discharge 3.5 let.h^(-1) treatment gave highest water horse power and pumping efficiency and least operating cost stood 0.202 hp and 70.72% , 0.71 $ / day respectively.

Maize (TZSR-Y variety) sown at 75x25 cm and leaf amaranth (NH Ac 23) seed rates at 2, 4 and 6 kg.ha^-1 drilled in rows 30 cm apart were grown sole and as intercrops in four replications and laid out in randomized complete block design during the rainy season of 2009 and 2010 on the Teaching and Research Farm, Ekiti State University, Ado-Ekiti, Nigeria. Amaranth yield was determined as weight of >15 cm tall plants uprooted weekly from one month old for four harvests; weight of shoots repeatedly cut at 15 cm fortnightly; and weight of seeds from mature inflorescences after threshing. Maize cobs were harvested dry, shelled, and sun-dried and weighed. Cropping system had no significant effect on leaf amaranth yield obtained by uprooting and repeated cutting but seed yield was higher in sole cropping in 2009. Yield obtained by uprooting and repeated cutting and seed yield increased with amaranth seed rate. In sole and intercropping systems, optimum marketable amaranth yields were obtained at 4 and 6 kg.ha^-1 by uprooting and 2 and 4 kg.ha^-1 by repeated cutting.  Intercropping slightly depressed maize grain yield and the reduction was higher as amaranth seed rate increased. Land Equivalent Ratio exceeded 1.0 in all intercropping systems and was highest at 6 and 4 kg.ha^-1 seed rate for marketable yield and seed yield, respectively at the established maize population.

Determination of pesticide residues in food is very essential in human health and it is becoming a major priority in the cocoa value chain. Hence, organophosphorous pesticide residues in dried cocoa beans from Ondo and Osun States, Nigeria were determined using Gas Chromatography – Mass Spectrometry (GC-MS) and the detected levels of these residues were compared with the European Union Maximum Residue Levels (EU MRLs). Samples were milled separately and 10 g milled samples were weighed into 40 ml Dichloromethane (DCM) in a beaker and later sonicated. The extracts were subjected to gel permeation chromatography to separate lipids from the extracts, which were later subjected to fractionation. Among the organophosphous pesticide residues detected in the samples from the states were dichlorvos, diazion, phosphamidon, pirimiphos-methyl, chlorpyrifos, isofenphos and carbofenothion with their being levels higher than EU MRLs, suggesting that the produce were not safe for human consumption and the residues could pose some health risk to the consumers.

Changes in soil properties, soil organic C (SOC) and total nitrogen (TN) stocks associated with different heating temperatures from 50, 100, and 150 kg/m2 dry biomass that provided for different heat intensities were compared with natural soil temperature of arable land adjacent to the burnt plots. Soil samples were collected in three replicates from control and burnt plots and soil temperatures were measured with soil thermometer placed at surface and sub-surface layers, while gas emissions were measured with sensitive gas dictators. The induced temperatures were highly variable at the soil surface whereas below 15cm depth, the temperature rise was not more than 370C. Modifications of various soil physico-chemical parameters caused by fire were related to increasing temperatures. The passage of fire promoted SOC and TN stocks, mean weight diameter, the aggregation of 2 mm stable structures which become even more resistant to disrupting action of water. The pH decreased to 5.4 at higher temperatures following burning before ashes mineralized. However, both organic matter and ECEC increased at increasing soil temperature. Potassium content remained surprisingly constant as the soil temperature increased. Air quality measurement revealed that NO2, SO2 H2S and CO2 were above the limits indicating air pollution through these activities. Despite the merits of quick release of occluded nutrients, heating temperatures of slash-and-burn method of land clearing altered soil and air quality.