JOURNAL OF AGRICULTURAL SCIENCE AND TECHNOLOGY (JAST)
Year:2014 | Volume:16 | Issue:1|Papers Count:20

This paper explores the distributive impacts of subsidy removal in agricultural sectors and related industry in Iran, using a social accounting matrix (SAM) -based price model.The structural path analysis approach is used to decompose the overall influences into direct, global, and total effects. The simulation results reveal that a shock therapy strategy, which involves the removal of all subsidies from all food producing sectors at once, amplifies the adverse effects of this policy option, especially on the low income households. Also, results indicate that removing subsidy from food producing sectors has distributional consequences for the Iranian households. The rural low income group is the most adversely affected group while the urban high income group is the least affected among the Iranian households. In addition, reducing subsidy in food industry sector has the largest impact on the households’ welfare. Based on the results of the path decomposition of the households’ expenditure, it is expected that less than 50 percent of the overall effects of subsidy removal appear almost immediately after implementing this policy.

The cotton bollworm, Helicoverpa armigera (Hubner), is one of the important polyphagous pests causing serious loss to many economically important crops in Iran. The goal of this experiment was to study the age-stage, two-sex life table of H. armigera on different bean cultivars including white kidney bean (cultivars Daneshkadeh, Pak, and Shokufa), red kidney bean (cultivars Akhtar, Naz, and Sayyad) and common bean (cultivar Talash) under laboratory conditions (25±1oC, 65±5% RH, a 16: 8 h light-dark photoperiod). The longest and shortest larval period and development time of total preadult H. armigera were 19.83±3.83 and 37.58±0.90 days on red kidney bean Akhtar, respectively, and 14.13±0.32 and 31.82±0.42 days on white kidney bean Pak, respectively.The lowest intrinsic rate of increase (r) was on red kidney bean Akhtar (0.115±0.009 day- 1) and the highest on white kidney bean Pak and common bean Talash (0.142±0.001 day- 1). The lowest and highest values of the net reproductive rate (R0) were on red kidney bean Akhtar (177.3±6.7 offspring) and white kidney bean Shokufa (270.1±6.7 offspring), respectively. The mean generation time (T) on different bean cultivars ranged from 37.03±0.05 to 44.64±0.07 days, which was shortest on white kidney bean Pak and longest on red kidney bean Akhtar. The results revealed that the cultivar Akhtar was the most unsuitable host for population growth of H. armigera.

In the present study, saffron was dried using a heat pump-assisted hybrid photovoltaicthermal solar dryer. The effect of different drying air temperatures at three levels (40, 50, and 60oC) and two different modes of the dryer (with and without heat pump system) were investigated on drying behaviour of saffron. After collecting the pertinent data, eleven drying models were used to describe drying characteristics of saffron. Quality characteristics of the dried products (including: colouring, aromatic strength and bitterness) were also evaluated. The results indicated that drying time decreased by 62% with increasing air temperature from 40 to 60oC. Moreover, applying heat pump with the dryer reduced RH of drying air and, consequently, enhanced drying rate and shortened drying period by 40%. A two-term drying model presented a relatively higher R2 and lower X2, MBE, and RMSE values at both modes of drying and, therefore, was selected to explain drying behaviour of saffron among the other models. The results of saffron quality evaluation showed that colouring characteristics of saffron improved with drying temperature and heat pump system. Meanwhile, aromatic strength of saffron increased with increasing air temperature. But, no significant change in bitterness was observed at different levels of temperature and heat pump system.

Present study examines whether there is any beneficial effect of magnetized water application on seedling emergence of maize seeds. Water from various sources like tap water, saline water (1, 500 ppm), canal water, and sewerage water was treated magnetically by passing it through 235 mT magnetic fields at 3 lpm flow rate. Seeds were soaked in water for 24 hours and planted in sand culture. Number of seedling emerged were counted on daily basis while growth data was measured 15 days after planting.Emergence indicators like Emergence Index (EI), Emergence Rate Index (ERI) and Mean Emergence Time (MET) were used to evaluate the germination of maize seed. Results of the present study revealed that application of magnetized water promoted the germination of maize seeds. Emergence index and emergence rate index values increased from 5.50 to 8.92 and 10.06 to 12.84 and the mean emergence time was reduced 17.90% for magnetized sewerage water in contrast to non-magnetized. Magnetized water treatment showed faster and heavier growth in all water types. Overall, the maximum increase in length and weight of emerged seedlings was noted with magnetized sewerage water. Since the results are based on limited laboratory scale study, further testing of magnetized water application in irrigated environment is suggested before making any concrete recommendations.

The objectives of this study were to identify a suitable mathematical model for describing the growth curve of Baluchi sheep based on monthly records of live weight from birth to yearling; and to evaluate the efficacies of nonlinear mixed effect model (NLMM) and the nonlinear fixed effect model (NLM) methodologies. Growth models were fitted to a total of 16, 650 weight–age data belonging to 2071 lambs. Five nonlinear growth functions of von Bertalanffy, Gompertz, Brody, Logistic, and Richards and two linear polynomial functions were applied. The growth models were compared by using the Akaike’s information criterion (AIC) and residual mean square (MSE). Among all nonlinear fixed effect models, the Brody function had the smallest AIC and MSE values, indicating the best fit for both sexes. The Brody fixed effect model compared with NLMM including one random effect of asymptotic mature weight. The model evaluation criteria indicated that the Brody mixed effect model fitted the data better than the corresponding fixed effect model. It can be concluded that, among the linear models, the polynomial of the third order and, among nonlinear models, Brody mixed model were found to best fit the Baluchi sheep growth data.

Calving records from April 1998 to September 2006 comprising 104, 572 calving events from 16 dairy herds of Iran were used to analyze the potential effect of dystocia on calf stillbirth and productive traits in Iranian Holsteins. Statistical analyses of production traits were performed using a linear mixed model procedure. Also, a logistic regression model was constructed to analyze the effect of dystocia on calf stillbirth. The odds of stillbirth was greater after severe dystocia [P<0.001; Odds Ratio (OR) =29.66]. Also, the odds of stillbirth were the highest for primiparous cows which calved with severe dystocia (caesarian). Cows that experienced caesarian at calving had the lower 305-day milk yield than other classes of dystocia (P<0.05). Cows that experienced caesarian at calving had the lower unadjusted, 305-day and mature equivalent fat yields than other classes of dystocia (P<0.05). The results of this study indicated the scope of economic and animal welfare opportunities associated with the reduction of dystocia by management and breeding in dairy herds.

The aim of this study was to analyze the polymorphisms existing in the 5’ flanking region, exonic, and some parts of the intronic regions as well as methylation analysis of the EDNRB gene in cattle and goat. These regions were sequenced in three different breeds of cattle including Sistani, Golpayegani, and Holstein and were compared with that of Marghoz goat. The results identified that this gene encodes 441 amino acid residues in cattle and goat with highly conserved domains between them. A total of 55 transition and 43 transversion mutations were observed in the 5’ and 3’ flanking and exonic regions. Among the six coding mutations in goat EDNRB gene, a missense mutation of C236>T resulted in substitution of Alanine-79 to Valine. The frequency of the T allele in the goat population was 0.77. In addition, an insertion of TG (29) repeat was identified at the -773 upstream of the gene in goat samples. The promoter region of the gene harbors two GC rich conserved motifs and transcription factor binding sites for GATA and SP1 in both species, which may modulate the expression of the gene. The methylation analysis of a 182 bp fragment of the 5’ region of the EDNRB gene, located at the fringe of the CpG island, was found to be completely methylated in both cattle and goat. Evolutionary analysis revealed that the cattle and goat EDNRB proteins were sisters in their own clade and dN / dS ratio demonstrated that the EDNRB gene underwent purifying selection during evolution.

The main objective of this study was assessment of hormonal treatments effects on sperm quality improvement in Barbus sharpeyi. Results showed differences in effects of treatments with LHRHa2, LHRHa2 combined with a dopamine antagonist (MET), and CPE (Carp Pituitary Extract) on parameters of sperm volume, motility, spermatocrit, biochemical indices of seminal plasma and sperm efficiency on artificial propagation, incubation survival, and deformities. Biochemical analysis of seminal plasma showed that the majority of parameters were affected by different hormonal treatments. In conclusion, the highest sperm quality of Benni fish could be achieved by application of LHRHA2 (10 mg kg-1+MET), LHRHA2 (5 mg kg-1+MET) and LHRHA2 (5 mg kg-1) at 8, 12, and 16 hours PHS, respectively.

Recently, some natural products have been used in the fields as alternative to synthetic compounds, to minimize the negative impacts to the environment. This study aimed to verify the effects of Neem-based bio-pesticide in causing acute toxicity for a fish and chronic toxicity for a microcrustacean. To this end, Danio rerio and Daphnia magna were exposed to various concentrations of a Neem-based oil formulation. In the first experiment, adults of D. rerio were exposed for 96 hours to different concentrations to determine the median lethal concentration (LC50-96h). For D. magna, first an acute toxicity test was performed to determine the median effective concentration (EC50-48h). Based on the EC50 established in the acute test, the concentrations for the 21-day chronic toxicity test were determined. Endpoints evaluated were reproduction (number of neonates produced) and size of D. magna. The median lethal concentration for the fish was 0.22 mL L-1, and the median effective concentration (EC50-48h) for D. magna was 0.17 mL L-1. In the chronic test, all concentrations affected reproduction and size of D. magna. The formulation tested may be hazardous to aquatic organisms.

In this study, the effect of addition of three different levels of microbial lipase (0, 4, and 8.0 g lipase in 100 kg milk) was investigated on the physiochemical properties, free fatty acids, textural properties, and microstructure of Lighvan cheese during ripening. The addition of lipase did not significantly affect pH, acidity, moisture, and salt content of Lighvan cheese, but increased its free fatty acid content considerably. It also increased hardness and decreased the brittleness of Lighvan cheese in all stages of ripening. The number and the mean diameter of fat globules, which were entrapped in casein network, were affected by all levels of the added lipase. Following the addition of lipase to Lighvan cheese and after 90 days of ripening, individual fat globules or their aggregates totally disappeared and some fingerprints of fat were observed. Disappearance of fat globules along with increase in protein matrix junctions leads to uniform structure of casein consisting voids which are produced from fermentation.

In this research, seeds of Iranian carob trees grown wild in Kazeroon city (Fars Province) were used to extract Iranian locust bean gum as a seed galactomannan.Chemical composition, solubility, and rheological properties of crude and purified gums were investigated and compared with a commercial (Sigma) locust bean gum (LBG) sample. Chemical composition of the purified Iranian LBG was similar to the commercial LBG, however, the protein content of Iranian crude LBG was higher. Solubility data showed that the Iranian crude LBG was partially cold-water soluble (~55% at 25oC) and needed heating to reach a higher solubility value (~71% at 80oC). Rheological properties of the solutions of the three LBG samples were investigated as a function of concentration and temperature (5-60oC) at shear rate range of 0.5-200 s-1. All three samples showed shear thinning behavior and Power law model was used to fit the experimental data. The Iranian LBG (crude and pure) was able to thicken aqueous solutions; however, its viscosity level was lower than that of the commercial LBG. Study of rheological properties of the three LBG samples at different pH levels (2.5-10) showed that they were significantly affected by pH. The intrinsic viscosities of the Iranian crude and purified LBG and commercial LBG were 3.95, 9.05, and 9.48 dL g-1, respectively.

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In thirty-three wild cherry (Prunus avium L.) accessions from Central Serbia, tree, leaf, fruit, and stone morphological characters were evaluated during three consecutive years.The goal was to detect relationships between the genotypes and to identify the most useful traits for discrimination among them. The study revealed a high variability in the set of the evaluated wild cherry accessions and considerable differences were found among them in all studied attributes. The majority of important correlations were determined among variables representing fruit and leaf size, and variables related to color. Cluster analysis distinguished wild cherry accessions into two distinct groups. In PCA, fruit and leaf traits such as leaf length and width, and fruit height, width, and weight, and skin flesh and juice color were predominant in the first two components, indicating that they were useful for the assessment of wild cherry germplasm characterization. These results indicate that these accessions must be conserved as valuable genetic resources to enrich the cherry gene pool and can be used for improving breeding efficiency of important horticultural traits worldwide.

The pomegranate fruits of cvs. Malas Yazdi and Malas Ashkezar were immersed in SA (1 and 2 mM from source of acytyl salicylic acid) for five minutes, in JA (0.3 and 0.4 mM from source of n-propyl dihydrojasmonate) for fifteen minutes, in CaCl2 (1 and 2%) for five minutes, and in distilled water for five minutes as control. Then, the fruits were stored in cold storage at 1.5±0.5oC and 85±5% relative humidity for 2 months. Every 21 days, samples were taken out of the cold storage and were kept at 20oC for 3 days before analysis. The analysis results revealed that treatments with SA, JA, and CaCl2 significantly reduced the chilling injury of pomegranate fruits. The lowest chilling injury index was observed in 0.4 mM of JA-treated fruits and the highest was for untreated fruits. Electrolyte leakage of fruits increased upon treatments of fruits with 0.3 mM JA and 2 mM SA, but it was not significantly affected by other treatments. Treatments of fruits with SA, JA, and CaCl2 had no significant effect on phenolic compounds, but the total soluble solids of fruit juices was increased. Our findings indicated that total antioxidant activity decreased in treatments with 1, 2 mM SA and 0.3 mM JA, but it was not significantly affected by other treatments.

A stable Agrobacterium-mediated transformation system was established using bialaphos as the selective agent in soybeans [Glycine max (L.) Merr.]. The cotyledonary node explants of the soybean cultivar ‘NY-1001’ were inoculated with the Agrobacterium tumefaciens strain EHA105, harboring the vector pCAMBIA3301 containing the gus gene as the reporter gene and the bar gene conferring bialaphos resistance. The highest frequency of GUS transient expression (92%) was obtained after inoculation and 4-day co-cultivation with A. tumefaciens strain EHA105. Efficient GUS expression was observed in regenerated shoots from explants after 4-day co-cultivation combined with culturing on shoot induction medium (SIM) without bialaphos for 7 days followed by 4 mg.L-1 bialaphos for 2 weeks. Bialaphos (4 mg.L-1 in SIM; 2 mg.L-1 in shoot elongation medium (SEM)) effectively selected the transformants. The putative transformants and escapes could be exactly distinguished by using a half-leaf GUS assay method to detect GUS expression in the elongated resistant shoots, which resulted in the shortening of culture period for the early detection of transformed shoots. The transformation efficiency of this system was 1.06%. The transgenic plants were verified by polymerase chain reaction (PCR), Southern blotting, and herbicide-resistant responses. All four T0 transgenic plants were fertile and transmitted the phenotypes of both gus and bar in a 3: 1 ratio to their progeny. These results indicate that the established system is suitable for further breeding of herbicide-resistant transgenic cultivars, as well as for functional genomics studies of soybeans.

Artemisia annua is still the only commercial source of Artemisinin. To date, a number of biochemical and molecular studies about Artemisinin’s biosynthetic pathway have been carried out. In metabolic engineering approach, isolation and characterization of promoters leads to an understanding of which cis-acting elements are responsible for the regulation of gene expression. DBR2 is a key enzyme in Artemisinin biosynthetic pathway.In order to allow chromosome walking beyond the 5’ -flanking region of DBR2, two specific primers were used in combination with 6 arbitrary primers in TAIL-PCR method. A 696bp upstream of DBR2 start codon was isolated and cloned. The subsequent sequence analysis using bioinformatics softwares revealed that there were several cisacting elements such as TATA-box, CAAT-box, and MeJA-responsive element, and several W-box and light-responsive elements inside the DBR2 promoter. These results can be helpful in understanding of artemisinin biosynthesis regulation and will facilitate metabolic engineering of the compound.

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The alternative use of non-selective herbicides in different years will reduce the possibility of weeds resistance to herbicide by avoiding the crops constant exposure to herbicide selection pressure. The photoperiod-sensitive genic male sterile (PGMS) rice with herbicide resistance will be convenient to the mechanization of hybrid seed production and weed control. In order to develop double herbicide tolerant transgenic PGMS rice, the optimized Epsps gene and the Bar gene were jointly introduced into 7001S, a japonica PGMS rice, by Agrobacterium-mediated transformation. The coding sequence of Epsps gene was optimized based on the codon usage of rice genes and the function of optimized Epsps gene was validated by real-time PCR analysis, enzyme-linked immunosorbent assay of EPSPS protein, and herbicide resistant assay in the obtained independent transformants. The highest relative expression level of EPSPS protein in leaf reached 9.02% of the total soluble proteins. The transformants of T2 generation withstood at least 3.332 g glyphosate /m2 at seedling stage, which was 2.7 times higher than that reported by Monsanto Company. The transformants harboring the optimized Epsps gene and Bar gene were also resistant to glyphosate and glufosinate simultaneously at seedling stage; the resistant dosages were 0.375 g glufosinate m-2 and 0.833 g glyphosate m-2.

Seed bank is a central topic for plant community restoration. We determined the potential and regeneration capacity of soil seed banks of woody plant patches in conservation of the vegetation in an alpine habitat, since vegetation has completely disappeared in some sites by intensive grazing in the habitat. The study was done in mountainous area of Alborz in Iran. A total of 20 individual shrubby patches were selected and two quadrats were established in and out of each patch. Soil samples were then collected from each quadrat in spring, 2011. Above-ground vegetation was estimated in each quadrat in the growing season. The soil seed bank was determined by Seedling Emergence method in the greenhouse. The results showed that the soil seed bank density inside the shrub patches was much higher than outside the patches. This differentiation was more pronounced for forbs. However, seed density of the between-patches was strongly correlated to seed density of the within-patches, indicating the so-called patch effect. Similarity between the soil seed bank and aboveground vegetation was lower inside the patches than outside. This study revealed that the limited woody patches that have remained in the study area could play an important role in conservation of herbaceous and palatable species by their positive effects on the aboveground vegetation and the soil seed bank.

The effects of banana continuous cropping on soil quality and chemical properties and crop yield were investigated under continuous cropping for 1, 3, 5, 7, 10, and 15 years in Hainan province, China. The results indicated that the contents of total N, total K, available K, NH4-N, exchangeable Ca, and available Cu tended to increase, while total organic C (TOC), available S, and available Zn tended to decrease with the increase of continuous cropping years at the four sampling stages. The contents of exchangeable Mg and available Fe and Mn were higher in the 3, 5, 7, and 10 years than in the 1 and 15 years at the four sampling stages. The values of pH, the contents of total P and available P decreased from 1 to 5 years and increased from 7 to 15 years at most of the sampling stages. Overall, average banana yield increased from 1 to 3 years and decreased afterwards. In conclusion, banana continuous cropping deteriorated soil quality as evidenced by increase of soil acidity, decrease of total organic C, accumulation of N, P, K, Ca and Cu, deficiency of Mg, S, Fe, Mn, and Zn and accompanying decline in banana yield. In order to improve the soil environment and sustain higher productivity under continuous-banana cropping system, application of balanced rate of fertilizers is of considerable importance.