JOURNAL OF AGRICULTURAL SCIENCE AND TECHNOLOGY (JAST)
Year:2013 | Volume:15 | Issue:6|Papers Count:19

Study of factors affecting farmers' participation in watershed development is crucial for planners to ensure that projects fit local beliefs, values, and conditions. A cross sectional survey was conducted to identify factors influencing farmers’ participation in watershed development projects in the Khorasan region of Iran. A two-stage random sampling technique was employed to select a representative sample. A total of 139 farmers (76 participants, vs. 63 non-participants) from 65 project villages were selected and interviewed with the aid of a pre-tested interview schedule containing open-ended as well as closed questions. The discriminant analysis indicated that such variables as legal title to dry lands, hectares and value of dry lands, age, technical knowledge, level of education, visiting of the model farmers, and the horizon of watershed planning, could correctly classify about 80 percent of watershed farmers as participant vs. nonparticipants. For better understanding of these determinants, a multiple regression analysis was also carried out which indicated that "technical knowledge" and "hectares as well as value of dry land" were the key determinants of farmers' participation in watershed development projects.

A method based on Machine Vision System (MVS) is hereby employed to evaluate grape drying through an assessment of the fruit’s shrinkage and quality during the dehydration. Experimental data as well as captured images are obtained at an air velocity of 1.4 m s-1 and different drying temperatures (50, 60, 70oC). The results indicated the effect of temperature on the moisture content, shrinkage and color changes. The moisture content along with color changes (DE) were modeled and linear regressions applied to correlate the fruit’s shrinkage as well as color features to the moisture content. The results obtained, displayed that there existed good linear relationships between the fruit’s moisture content, and shrinkage as well as color. The results also revealed that the moisture content vs. quality of the grape could be online evaluated through machine vision during the drying process.

Effect of different CO2 concentrations on sucrose metabolizing enzymes and on carbohydrate metabolism was studied for eight blackgram (Vigna mungo L. Hepper) genotypes grown in open top chambers under ambient (380 mmol mol-1) vs. elevated CO2 (550 and 700 mmol mol-1) levels. The higher acid invertase activity over neutral invertase indicated the major role of acid invertase in sucrose breakdown. Higher acid invertase activity over Sucrose Synthase (SuSy) suggested the major role of invertase in sucrose breakdown and sucrolysis. Sucrose Phosphate Synthase (SPS) activity did not match with sucrose pool sizes in mature leaves and rather varied among genotypes. Plants exposed to higher CO2 concentrations showed higher starch and sucrose contents as compared with those exposed to ambient CO2. Leaf starch content being found several-folds higher than sucrose throughout the study indicated its major role in regulating assimilate partitioning. Increase in glucose vs. fructose concentrations for genotypes grown under elevated CO2 conditions ranged from 20 to 90% and from 10 to 140%, respectively. The hexoses/sucrose ratio for elevated CO2 concentration was approximately 0.8-1.6, however for ambient CO2 content it approximately amounted to unity. Genotypes IC436720, IC519805, IC343952, and IC282009 with low hexose/sucrose ratio representing high CO2 assimilation along with high sucrose formation indicated better tolerance to elevated CO2 for carbon partitioning and carbohydrate metabolism. The up-regulation of leaf carbohydrate metabolizing enzymes of low hexose/sucrose as well as low sucrose/starch ratios for the genotype IC436720 (as compared with other genotypes) improved its photosynthetic capability which coupled with its better efficiency of carbon partitioning (indicative of better acclimation to elevated CO2) could prove beneficial to its growth and productivity in the future change of climatic conditions.

The aim followed in the present paper was to evaluate the slaughter body and carcass weights as well as the characteristics of hide and leather in Dromedaries (one-hump) and in the crossbred (C. bactrianus´C. droedarius) camels. Fourteen camels from each sex (female and male) representing two genotypes at 21 months of age were utilized. Slaughter weight, hot and cold carcass weights, dressing-out percentage, wet and dry salting hide and leather properties were assessed. There were significant differences in slaughter weights between Dromedary and crossed types (339±10.7 vs. 372±11.1 kg) and as well between male vs. female camels (382±9.7 vs. 326±10.6 kg). Moreover, while the effect of sex was significant on wet hide weight (34±1.2 vs. 29.3±1.2 kg for males and females, respectively), the difference observed between males and females regarding the thickness of hide was non-significant (P>0.05). Breaking force, tensile strength and elongation of the leather samples decreased with increase in their thicknesses. It was found out that the obtained leather from the camel benefited from such valuable mechanical characteristics as tensile strength and extension with no variations being observed as due to the animal’s sex or genotype.

The data set employed in this study was comprised of a number of 6,800 records of lamb’s longevity and their survival rate, collected from 1989 through 2009, from the Lori- Bakhtiari experimental flock at the Shooli Station in Shahrekord, Iran. The data were analyzed using linear models and proportional hazard models with Weibull function. These models included fixed factors and direct additive genetic, maternal additive genetic, maternal common environmental and residual random effects. Genetic parameters were estimated using Restricted Maximum Likelihood (REML) procedure fitting a sire model as well as animal models including different combinations of direct and maternal effects. Estimates of direct heritabilities of longevity and survival rate from different linear models were low (0.01 to 0.09). The maternal heritability ranged from 0.00 to 0.04, and decreaced with increase in the age of lambs. The estimates of heritability in logarithmic scale, original scale and effective heritability obtained from the sire and animal models with Weibull function were medium to high (0.08 to 0.55) and were higher than those estimated through different linear models. The maternal heritability estimated through Weibull models decreased with the age of lambs (0.25 to 0.01). These results indicated that the accuracy of the Estimated Breeding Values (EBV) of lambs’ survival rate from birth up to yearling age, using linear animal models vs. proportional hazard models, would be low vs. medium to high, respectively. Both animal and maternal genetic effects should be considered in the models for improving the survival rate up to 4 months of ages.

ABCG2 (ATP binding cassette subfamily G member 2) gene, located on chromosome 6 encodes the ABCG2 protein that transports various xenobiotics, cytostatic drugs across the plasma membrane as well as cholesterol into milk. A single nucleotide change (A/C) in base 86 of exon 14 is capable of encoding a substitution of tyrosine with serine in the ABCG2 gene and increase milk yield while decreasing milk fat and protein concentrations. The major aim followed in this research was to study Single Nucleotide Polymorphisms (SNPs) of ABCG2 gene and their association with milk production traits in Iranian Holstein bulls. Genomic DNA of 105 ified bulls was extracted from semen samples using highly Pure PCR template preparation kit. Primers were designed through Oligo software (Version 5.0) and utilized in PCR. Then the PCR fragments were sequenced. The A/C substitution in base number 86 of exon 14 was observed with 2% frequency which affected protein percentage (P<0.05). Some SNPs were detected for the first time in intron 13, exon and intron 14 in comparison with sequences in the NCBI database. A deletion mutation in base number 20 (T/-) and a missense mutation in base number 67 (A/G) of exon 14 that cause the substitution of serine with glycine were discovered which were significantly associated with protein yield and fat percentage, respectively (P< 0.05). Furthermore, significant association was observed between fat percentage and mutations in base numbers 4,133 (T/C) and 4,137 (T/G) of intron 13 (P<0.05). Substitutions in base numbers 2 (T/C) and 55 (G/C) of intron 14 resulted in a significant effect on fat yield and fat percentage (P<0.05).

Baluchi sheep is considered as the most common breed in Iran, constituting about 30% of total sheep population, approximately 15 million heads. This research was designed to study the incidence of mutation in two loci of IGF-I (Exon 3) and ADRB3 (Intron) along with their ssociation with body weight traits in Baluchi sheep population. Following DNA extraction from 190 Baluchi sheep, two pairs of primers were designed to amplify each gene. PCR-SSCP (Single-Strand Conformation Polymorphism) and DNA sequencing were employed to detect polymorphism of the mentioned genes. Two banding patterns were detected for IGF-I locus. The frequencies of AA, AB were recorded as 0.89, 0.11, respectively in IGF-I locus. As for ADRB3, two patterns corresponding with two genotypes (their frequencies mentioned in parentheses) of AA (0.85) and AB (0.15) were identified. One SNP change was observed in ADRB3, and one in IGF-I. A previously reported SNP was detected in exon 3 of IGF-I. The effects of IGF-I and ADRB3 polymorphism on the corrected phenotypes for body weight at birth (BW), weaning (WW), 6 months of age (6MW), 9 months of age (9MW) and 12 months of age or Yearling Weight (YW) were examined using least square methods. No significant association was detected between the polymorphism of IGF-I and body weights. As for ADRB3, the genotype AA was found out to exert a significant positive effect on 6MW (AA, 30.20±1.85 kg day-1; AB, 27.67±1.98 kg day-1; P<0.05).

Current interests towards lowering fat content in food products and producing healthier and safer foods, have convinced ice cream manufacturers to substitute milk fat in ice cream with either carbohydrate or protein based fat replacers. In the present work, reduced-fat ice cream (5% fat) was produced using milk protein concentrate (65%) and inulin as fat replacers (0, 2 and 4%) as well as two types of commercial stabilizer-emulsifier blends (Stab-IC80 and Stab-6924) at levels of 0.3 and 0.4%. Rheological, physicochemical and sensory properties of ice cream mix and final ice cream were evaluated. All the mixes were pseudoplastic fluids with apparent viscosity values decreasing with increasing shear rate. Mix viscosity and consistency coefficient increased while flow behaviour index decreasing by use of MPC (Milk Protein Concentrate) and inulin and as well with an increase in either type of stabilizer level. Ice cream hardness was not affected by type and amount of fat replacer and stabilizer but overrun values decreased with increasing MPC, inulin and stabilizers’ level in the product formulation. In general, samples containing Stab-IC80 had greater values of overrun and melting resistance than samples with Stab-6924. According to panel test results, the highest score for sensory evaluation was given to sample containing 2% inulin.

Rice bran is a major by-product of the rice milling process that contains high amounts of fiber, proteins, fats, vitamins, minerals as well as antioxidants and hence can be utilized in enriching food products. The main aim followed in this study was to determine the effects of rice bran of variable particle sizes (53, 125 and 210 mm) and its quantity (0, 5, 10, 15 and 20%) on the quality of batter and on sponge cake. Increasing bran quantity and particle size increased batter density and consistency. Using a higher quantity of bran with larger particle sizes increased cake density and weight of the cakes (after being baked) while decreasing the cake volume. Textural properties of the samples as determined instrumentally showed that maximum compressive force and the firmness increased, while cohesiveness and springiness decreased with increase in the contents of bran and increase in its particle size. Cake crust color became darker, more reddish and less yellowish with inclusion of rice bran. Increasing the levels of rice bran, negatively affected taste, crust and crumb color as confirmed by the sensory panel. Overall, it was found that addition of 10% rice bran with particle size of 125 mm resulted in the most desirable cake quality.

The present study was carried out to investigate the effect of various refining processes’ conditions on conjugated dienes in soybean oil. Conjugated dienes contents of soybean oil were found to undergo reduction in neutralization and bleaching steps while being increased in deodorization. It was observed that alkali refining (neutralization) through 12 and 14oBé, bleaching with either acid activated clay or a mixture of acid activated clay plus activated carbon at 110oC along with deodorization at 220oC and at 4 or 8 mbar had the highest effect on reduction of conjugated dienes in soybean oil. Conjugated dienes were in good correlation with peroxide value, free fatty acids, Totox value and as well with p-anisidine value in each step. Overall, alkali refining proved to be the most effective step in reduction of conjugated dienes, free fatty acids and oxidative stability index. Peroxide value, p-anisidine and Totox values changed during refining and got significantly decreased in deodorization.

The flowering and fructification period of the Chilean strawberry (Fragaria chiloensis (L.) Duch.) is restricted to approximately 2 mo, which seriously limits the commercial development of the species. The objective of the current investigation was to identify Inter Simple Sequence Repeat (ISSR) polymorphisms associated with flowering duration in accessions of F. chiloensis. The flowering duration data related to 41 accessions obtained over 3 years were analyzed, and a set of 40 ISSR primers tested. Two clusters were obtained through the Partitioning Around Medoids algorithm, with 23 vs. 18 accessions, and 64.1 vs. 95.6 days of flowering, respectively. Flowering duration, between the two groups, was significantly different. The years also revealed a significant effect, on flowering duration, between the two groups. Ten of the ISSR primers tested revealed reproducible and consistent banding patterns, displaying a total of 106 putative loci, of which 79 were polymorphic. Three ISSR loci (811779, 844670, 841980) were identified owing to their significant contribution to the differentiation among the accessions. Similarly, three ISSR loci (811600, 8121180, 841980) exhibited a significant correlation with the flowering duration variation. Locus 841980, which presented the highest level of correlation with flowering duration, was isolated, cloned and sequenced, but it showed only a low level of homology with the relevant sequences published in the GenBank database. The identified loci showing high correlation with the flowering time could help build Quantitative Trait Loci (QTL) maps for selection and improvement programs in the Fragaria sp. genus or other related species.

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Application of edible coating as a way of prolonging the shelf-life of perishable fruits and vegetables is promising. Two plum cultivars (Stanley and Giant) were treated with 1% Chitosan and then stored at 0-1oC and relative humidity of 90±5% for 40 days. Changes in weight loss, respiration rate, fruit firmness, soluble solid content, titrable acidity, pH, ascorbic acid as well as decay rate were periodically recorded. The results indicated that Chitosan coating was effective in reducing weight loss, respiration rate as well as decay rate. A parallel trend in weight loss and decay rate was observed for both cultivars. Comparing the two cultivars, ‘Giant’ exhibited higher weight loss and respiration rate. Weight loss was mitigated through Chitosan application due to its positive effect in reducing respiration. In addition, Chitosan coating resulted in the retainment of a higher content of titrable acid, pH as well as firmness in either cultivar. However, total soluble solids and ascorbic acid contents were not significantly affected by the coating. The results finally indicated that Chitosan treatment is an effective strategy for maintaining organoleptic characteristics and as well for the prolonging of postharvest life in plums.

Advection-diffusion equation and its related analytical solutions have gained wide applications in different areas. Compared with numerical solutions, the analytical solutions benefit from some advantages. As such, many analytical solutions have been presented for the advection-diffusion equation. The difference between these solutions is mainly in the type of boundary conditions, e.g. time patterns of the sources. Almost all the existing analytical solutions to this equation involve simple boundary conditions. Most practical problems, however, involve complex boundary conditions where it is very difficult and sometimes impossible to find the corresponding analytical solutions. In this research, first, an analytical solution of advection-diffusion equation was initially derived for a point source with a linear pulse time pattern involving constant-parameters condition (constant velocity and diffusion coefficient). Hence, using the superposition principle, the derived solution can be extended for an arbitrary time pattern involving several point sources. The given analytical solution was verified using four hypothetical test problems for a stream. Three of these test problems have analytical solutions given by previous researchers while the last one involves a complicated case of several point sources, which can only be numerically solved. The results show that the proposed analytical solution can provide an accurate estimation of the concentration; hence it is suitable for other such applications, as verifying the transport codes. Moreover, it can be applied in applications that involve optimization process where estimation of the solution in a finite number of points (e.g. as an objective function) is required. The limitations of the proposed solution are that it is valid only for constant-parameters condition, and is not computationally efficient for problems involving either a high temporal or a high spatial resolution.

Continuing agricultural expansion and urban development in Saudi Arabia, (located in an arid climate), together with an increased demands for more water supplies, calls for more efficient irrigation practices, and an increase in Crop Water Productivity (CWP). Throughout the present study, a deficit irrigation system was investigated for its impact on soil salinity, crop response factor (Ky), CWP, and a crop, namely cucumber’s (Cucumis sativus L.) yield. Cucumber seeds were planted in a greenhouse equipped with drip irrigation system. The crop evapotranspiration (ETc) was assessed through Pan Evaporation method (PE) and estimation based upon Penman-Monteith equation (PM). The results revealed good agreement between PE and PM ETc. The irrigation treatments consisted of four levels of ETc (40, 60, 80, and 100% of ETc) in addition to the traditional one as practiced by local farmers. At the 60 and 80% ETc treatments, the deficit irrigation was tested at different growth stages (Initial, developmental, middle, and late stages of crop growth). Each of the treatments was carried out in three replicates. The results showed that soil salinity in general increased with decreasing level of applied water. The crop cucumber could tolerate shortage of water during the middle season growth stage, when the Ky values ranged between 0.57 and 0.76. The level of water used up in 100% ETc treatment was much lower than that in the traditional drip irrigation as practiced by farmers. In other words, the CWP values increased with water consumption being decreased. The results also indicated that the highest values for CWP were found for the most stressed treatment of 40% ETc, while on the other hand the overall crop productivity had decreased.

A Fully Fuzzy Linear Programming (FFLP) formulation for the reservoir operation of a multipurpose reservoir in presented in the ongoing paper. In the real world, water resources systems usually have complexities among social, economic, natural resources and environmental aspects, which lead to multi-objective problems of significant uncertainties in system parameters, objectives and in their interactions. These uncertainties in FFLP reservoir operation model are considered by being treated as fuzzy sets. In the present study, an FFLP reservoir operation model is developed where all parameters and decision variables are fuzzy numbers. The developed model is demonstrated through a case study of Jayakwadi reservoir stage-II, Maharashtra, India with the objectives of maximization of annual releases for irrigation and hydropower generation. The FFLP reservoir operation model is solved to obtain a compromised solution by simultaneously optimizing the fuzzified objectives and the corresponding degree of truthfulness, using linear membership function. The degree of correspondence (Correspondence) obtained is equal to 0.78 and the corresponding annual releases for irrigation amount of 367 Mm3 and while annual releases for hydropower generation being 216 Mm3. the present study clearly demonstrates that, use of FFLP in multipurpose reservoir system optimization presents a potential alternative to attain an optimal operating policy.

Fennel (Foeniculum vulgare Mill.) benefits from a lot of useful medicinal properties. Iran is known as one of the main producers of fennel. In spite of high medicinal values, fennel’s cultivation is not economically feasible, mainly due to its low yield. It grows wild in different areas in Iran from where diverse ecotypes have evolved. Genetic variance and heritability estimates of traits in a plant’s primary germplasms are needed before planning of a new breeding program. In the present study the genetic diversity and broad sense heritability for 50 fennel ecotypes were assessed under field conditions for a duration of two years. Seed yield, essential oil content and some morphological traits were recorded during a two experimental years. Through stepwise regression, the yield affecting traits and essential oil content were determined. During the first and second experimental years the most effective traits affecting essential oil content were found to be the number of leaves per plant and days to 50% flowering, respectively. The weight of dry biomass affected seed yield the highest during any of the two years and for each separate year. The broad sense heritability during the two experimental years, for essential oil content and seed yield, were 0.46 and 0.63, respectively. However, some such traits as, days to 50% flowering and length of middle internodes showed higher comparative heritability (0.90 and 0.79, respectively). The high heritability of the studied traits in this germplasm indicates the germplasm’s high genetic potential to be made use of in breeding programs.

Cry genes encoding Cry proteins toxic to Lepidoptera, Coleoptera and Diptera species were studied in thirty seven B. thuringiensis strains isolated from twelve naturally infested Heliothis armigera larvae. To further confirm the isolates, two groups of species-indicative biochemical tests were applied while discriminative biochemical tests being employed to figure out the repetitive strains. A PCR experiment was performed using five sets of universal primers for cry1, cry2, cry3, cry4, cry7.8 genes. All strains reacted appropriately, for B. thuringiensis, to the biochemical tests and while the reactions to the discriminative tests being varied. Based upon the results of the discriminative tests, twenty four non-repetitive strains were selected and employed in the PCR assay. Each of the selected strains presented one cry gene, at least; cry1 being the most frequently detected one (91.7%), followed by cry2 (87.6%), cry3 (50%) and cry4 (42%) but no isolate harbored a coleopteran-active cry7.8 gene. All the strains presented combinations of two or more cry genes: 20% presenting cry1+cry2, 12.5% cry1+cry3, 4% cry2+cry4, 20% cry1+cry2+cry3, 20% cry1+cry2+cry4, 4% cry1+cry3+cry4 and 12.5% carrying all the four cry genes studied and only one strain bearing a single cry gene. The cry1-cry2 combination was common in many strains (72.5%). Genetic characterization of this collection provides an opportunity for selection of strains with improved and multiple insecticidal toxicity.

Degraded soils in Northwest China are mostly nonproductive due to imbalanced nutrient and inadequate water supply. The effects of manure application at three different rates (7.5, 15.0, and 22.5 t ha–1) combined with chemical fertilizers on soil water and Water-Use Efficiency in maize [compared with chemical fertilizers (control)], under semi-arid conditions in dark Loessial soil and over a period of four years were studied to provide scientific support for water management. High manure application significantly reduced soil water evaporation throughout the fallow period as compared with control. It significantly increased soil water storage capacity at the big trumpet growth stage of the crop, and with the fertilization application years continued (P<0.05). Manure application improved soil water holding capacity at the tasseling and grain filling stages. It decreased evapotranspiration at the jointing–big trumpet and tasseling–grain filling stages. It as well improved Water-Use Efficiency by 16.67 to 295.42% at the jointing-big trumpet stage vs. 9.38-68.96% at the tasseling-grain filling stage and 8.51 to 36.58% for the whole growth period of the crop maize. With a continuation of the fertilizer application years, water-use efficiency at the tasseling-grain filling stage was significantly improved with increasing manure application rates (P0.05). Medium and High Manure application rates significantly increased water-use efficiency at the big trumpet–tasseling and grain filling-maturity stages as compared with control (P<0.05). With manure application years continued, soil nutrient was no longer the major factor limiting the crop’s water-use efficiency. The most promising manure application rate adopted to improve water-use efficiency was recorded as 15.0 t ha-1.