Journal of Agricultural Science and Technology
Volume:23 Issue: 5, Sep 2021

In recent years, the use of photoselective shading nets to mitigate the harmful high radiation caused by the increase in temperatures is growing. The objective of this work was to study the positive effects - in terms of yield and profitability of photoselective shade nets in two types of pepper: Lamuyo (cultivars Alcudia and Pompeo) and California (cultivars Bendigo and Cayetano). The weekly yields, classified into different calibre, were analysed over two years, and for the analysis of economic profitability, the Equivalent Annual Value (EAV) was used with an analysis of sensitivity. The yields obtained with the pearl-colored net giving 30% shading were superior to open cultivation (no netting), in all the studied cultivars; in particular, Cayetano and Pompeo had 136 and 86% greater yields, respectively. This same trend was observed for the red-colored net giving 30% shading, with 88 and 74% increase in yield in Cayetano and Pompeo, respectively. In economic terms, the EAV was superior with the use of the pearl net, especially for the cultivars Alcudia and Cayetano - being €14,864 and €13,326 ha-1 yr-1, respectively. The yield and profitability were better for the crops grown under the pearl-colored photoselective net, especially for cultivars Alcudia and Cayetano. The sensitivity analysis showed that the probability of obtaining negative returns was higher in the absence of netting, while under the shade nets it was below 10%.

Peoplechr(chr('39')39chr('39'))s participation is an important strategy for successful watershed management. This study aimed to identify and prioritize the factors prevent people from participation based on local peoplechr(chr('39')39chr('39'))s and expertchr(chr('39')39chr('39'))s viewpoints in Vers watershed. These factors were identified and categorized using literature reviews and interviews with experts and local residents. The validity and reliability of the questionnaires were checked by experts and Cronbachchr(chr('39')39chr('39'))s alpha test respectively. The sample size was also calculated by the Cochran formula. Finally, the indicators and sub-indicators which preventing peoplechr(chr('39')39chr('39'))s participation were prioritized using the Fuzzy Analytical Hierarchy Process (FAHP) and Friedman test. The results indicated that the views of experts and local residents about the preventing factors are in some cases consistent and in others inconsistent. In general, managerial and economic indicators have a greater role in preventing people from participating than social and educational ones. Experts believe that the factors X13 (lack of timely and complete project budget allocation) and X2 (local disputes) have respectively the most and the least degree of importance. But local residents ranked X7 (lack of multipurpose projects) and X6 (weakness in teamwork) respectively as the most and the least important factors. These differences imply that in addition to the viewpoints of experts, policy-makers must also consider the views of stakeholders on the factors preventing their participation. These findings can be appropriate and practical for executive officials since, removing these participation barriers especially the high-priority ones will increase the stakeholders’ participation level.

The present study tested the Protection Motivation Theory (PMT) in explaining farmers’ response to renewable energy in Zanjan County, Iran. The study further investigated the direct and indirect influence of knowledge on motivation to use Renewable Energies (REs) through PMT variables. The target population of this study comprised farmers in Zanjan County. Multistage sampling method was employed for sampling procedures and sample size was determined using G*Power software (n= 287). To test the study hypothesis, a multivariate technique of structural equation modeling was applied. The results indicated that the PMT threat appraisal variables comprising perceived vulnerability, severity, and intrinsic reward had statistically positive relationships with the farmers’ motivation to use renewable energies. Also, the results revealed that all PMT coping appraisal variables had a statistically significant relationship with the farmers’ motivation to use renewable energies. In addition, the results of full structural model specified that farmers’ knowledge directly and indirectly (through PMT variables) had a statistically significant effect on the farmers’ motivation to use renewable energies. The model, including knowledge and protection motivation theory variables, explained about 71% of the farmers’ motivation to use renewable energies. Therefore, the results revealed the applicability of the PMT in explaining farmers’ response to renewable energy in Iran. Thus, it is suggested that the future studies could use the extended model of PMT by considering the pre-influence of knowledge of renewable energies.

The aim of this study was to evaluate the effects of feed supplemented with different levels of Selenium Nanoparticles (SeN) on growth, survival, and biochemical indices of Acanthopagrus latus. Yellow-tail seabream fish with a mean weight of 52±3 gwasfed with four experimental diets containing 0, 0.5, 1, and 2 mg kg-1 SeN for 8 weeks. At the end of the experiment, the fish fed 0.5 mg kg-1 SeN showed a significant improvement of weight gain compared to the control (P< 0.05). Specific growth rate, feed conversion ratio, and survival were not significantly different between treatments (P> 0.05). The lowest activity of alkaline phosphatase, alanine amino transferase, creatinine phosphokinase and cholesterol were observed in 0.5 mg kg-1 SeN treatment, which was significantly lower than the control (P< 0.05). Although aspartate amino transferase, lactate dehydrogenase, triglyceride and creatinine were not significantly different among experimental treatments (P> 0.05), total protein and albumin levels were significantly increased in the 1 and 2 mg kg-1 SeN treatments compared to the control group. The highest level of globulin was observed in the 2 mg kg-1 SeN treatment. According to the results, the addition of 0.5 mg kg-1 SeN to fish feed could improve growth and biochemical parameters.

The efficiency of Carboxymethyl Cellulose (CMC) based Chickpea Hull Polysaccharides (CHPS) edible coating with regards to shelf life and physicochemical properties of cherry tomatoes were determined. Cherry tomatoes were coated with various CHPS concentrations (0.25, 0.50, 0.75 and 1.00%) to preserve cherry tomatoes during storage at 20◦C. The CMC-incorporated CHPS coatings were found effective to reduce the respiration rate, weight loss, firmness, lycopene content, total soluble solid, vitamin C, total polyphenols, and to improve the overall likeness of fruit compared with the control. All these effects were noted to be dose-dependent. Taken together, using CMC-incorporated CHPS coatings could prolong the shelf life of cherry tomatoes.

Nowadays, various forms of medicinal plants are used for different purposes such as improving the qualitative attributes, partial replacement of nitrite, and increasing the overall acceptance and shelf-life of meat products. In this research, 10, 20, and 30 mg/kg of Carum copticum extract, 40, 50, and 60 mg/kg of Salvia officinalis extract, and a combination extract (15:30) were used as partial replacements of nitrite in the sausage formulation. Then, the physicochemical, microbial  and sensory tests were performed on all treatments and control sample over 45 days. The results showed that treatment with 60 mg/kg S. officinalis extract had the lowest pH value. The lowest peroxide value was related to treatment with 40 mg/kg S. officinalis extract, which showed a significant difference with the control sample. In contrast, the lowest cooking loss was reported for treatment with 30 mg/kg C. copticum extract. The control sample showed the highest microbial count. Treatment with 60 mg/kg S. officinalis extract had the least total count of bacteria and C. perfringens. In contrast, the least count of coliform, mold, and yeast was found for treatment with 40 mg/kg S. officinalis extract. In terms of sensory attributes, treatment with 30 mg/kg C. copticum extract had the highest color and flavor scores, while the highest consistency and overall acceptance scores of all treatments were related to 20 and 10 mg/kg C. copticum extract, respectively. As a conclusion, treatment with various concentrations of S. officinalis extract had better acceptability and more effects on the sausage quality.

Doogh, a favorite acidic dairy drink, usually sufferd from low stability and swelling due to microbial activation, protein aggregation and consequently phase separation which happens at low pH. In this study optimization of doogh powder production stabilized by pectin and tragacanth was performed using response surface methodology for selection of appropriate hydrocolloid and processing condition. The results showed that the quality of doogh powder strongly depends upon the spray drying temperature and type of hydrocolloid addition. Optimum operating conditions were found to be an inlet air temperature of 122 ºC and stabilization using tragacanth, under which moisture content, bulk density, solubility, Carr index, serum separation, color (L factor), pH, Hausner ratio, and porosity were 5%, 0.31%, 88%, 37, 65%, 89, 4.33, 1.59% and 73.5%, respectively.  Evaluation of sensory attributes (color, odor, flavor, consistency, and total acceptance) confirmed that there was no significant difference (p>0.05) between dried doogh powder produced in optimized conditions and freshly prepared sample.

English grain aphid, Sitobion avenae (Fabricius), is an important worldwide phloem-feeding pest of wheat due to direct sucking damage and transmission of viruses. Here, we tested the effects of six treatments on the fitness traits of S. avenae including: (1) Wheat with a 6-days aphid infestation, (2) Wheat sprayed with Biomin zinc, (3) Wheat seed treated with Bacillus subtilis, and (4 and 5) Combined treatments of Biomin zinc+pre-infestation and B. subtilis+pre-infestation as well as (6) A control treatment. Results revealed that there were significant differences among treatments concerning some allelochemical contents and aphid fitness traits. Treated with B. subtilis+pre-infestation and B. subtilis increased the total contents of phenol in the wheat leaves versus Biomin zinc+pre-infestation (183.63 mg g-1 FW). The net Reproductive rate (R0) of S. avenae was significantly reduced by B. subtilis+pre-infestation (1.533 offspring per adult) compared to the control (6.887 offspring per adult). Treated with B. subtilis+pre-infestation (0.022 d-1) significantly reduced the intrinsic rate of increase (r) of S. avenae compared with the control (0.105 d-1). The lowest (0.024) and highest (0.058) Nymph Growth Index (NGI) of aphid were found on B. subtilis+ pre-infestation and the control, respectively. Hence, it was concluded that B. subtilis+pre-infestation in wheat plants can induce systemic resistance to S. avenae, which can be used in the IPM of this aphid.

The present paper contains a review of the tribe Eryciini (Tachinidae: Exoristinae) that occur in Iran. Twenty-six species belonging to 15 genera are reviewed. The collected data on 20 species are provided. Of these, seven genera and 16 species are newly recorded. Distribution and host information are briefly summarized. The diagnostic characters of the new records species are given. The key to the species found in Iran is also provided.

This investigation was conducted to determine the effects of salinity stress on some physiological and biochemical parameters of common bean (Phaseolus vulgaris L.). Three levels of NaCl (0, 100, and 200 mM) were applied to four common bean genotypes. In the subsequent steps, chlorophyll content, relative water content (RWC), electrolyte leakage index (ELI), Na+ and K+ concentrations, the K/Na ratio, malondialdehyde (MDA) content, total protein content, and proline concentration were determined and compared. Moreover, the activity of antioxidant enzymes catalase (CAT), ascorbate peroxidase (APX), polyphenol oxidase (PPO), and guaiacol peroxidase (GPX) were analyzed. Content of Chl a, Chl b and carotenoid decreased by increasing the intensity of salinity stress along with the SPAD value. RWC dropped and ELI incremented by augmenting salinity together with the K/Na ratio. The results revealed that MDA and proline concentrations significantly increased under the mentioned conditions. Activities of antioxidant defense enzymes were altered notably. Total protein content mitigated under salt stress. Jules and 201 were detected as tolerant genotypes during this experiment.

Water deficit is a major factor limiting plant productivity of fruit quantity and quality, particularly in arid and semi-arid regions of the world. The total yield, fruit physical characteristics and nutritional value of four drought tolerant tomato genotypes (KSU-TOM-102, KSU-TOM-106, KSU-TOM-107 and TL–01860) were evaluated in response to deficit irrigation (DI) under field conditions. Three levels of crop evapo-transpiration (ETc; 50%, 75% and 100%) were applied at three different growth stages (vegetative, flowering and fruiting stage) to the four tomato genotypes. Tomato genotypes differed in their responses to water deficit. Among different genotypes, KSU-TOM-102 recorded the highest average total yield (89.54 t.ha-1) under irrigation treatment with 100% of ETc during all stages as well as 75% of ETc during the fruiting stage. But, in general, total yield decreased under water deficit. Significant (P≤0.05) differences in fruits quality characteristics exerted by irrigation water treatments, tomato genotypes and their interactions. Irrigation with water at 50% ETc at all growth stages significantly (P≤0.05)  increased vitamin C, titratable acidity, total soluble solids and total sugar contents for tomato ‘KSU-TOM-107’ followed by ‘KSU-TOM-102’. But, this increase in nutritional value was accompanied with decrease in total yields by nearly 40-50%.   KSU-TOM-102 irrigated with water at 75% ETc at fruiting stage or vegetative stage recorded 0% and 12% reduction of the total yield, respectively, while maintaining good nutritional value as compared with 100% of ETc during all stages. Therefore, these treatments can be recommended as irrigation management strategy for tomato ‘KSU-TOM-102’ production under field conditions.

Gerbera is one of the significant cut flower crops worldwide suffering from loss of flower quality induced mainly by Calcium (Ca) deficiency. In this research, the influence of Humic Acid (HA) and Ca in nutrient solution was studied on the growth parameters of gerbera. A completely randomized hydroponic experiment was designed by adding HA (0, 100, 500, and 1,000 mg L-1) and Ca (3.5 and 7 meq L-1 nutrient solution) to the nutrient solution of gerbera, with three replications. The effects of the treatments were evaluated on the growth, protein content, proline content, transpiration, CO2 assimilation, photosynthesis, SPAD value, number of harvested flower, and antioxidant activity in gerbera cv. Malibu. Results showed that decreasing Ca level to 3.5 meq L-1 decreased Superoxide Dismutase (SOD), Peroxidase (POD), and CO2 assimilation. However, this treatment caused an increase in Malondialdehyde (MDA), protein content, proline content, chlorophyll, and photosynthesis. Transpiration and number of harvested flowers were not affected by Ca concentration significantly. The highest level of HA (1,000 mg L-1) increased POD and transpiration (30 and 11%, respectively). However, SOD and protein content increased at 500 and 1,000 mg L-1 HA levels. When HA was accompanied with Ca, SPAD value, transpiration, and CO2 assimilation were improved, especially at high levels of HA (500 and 1,000 mg L-1) and higher level of Ca (7 meq L-1 Ca). The results suggested that HA could increase the number of harvested flowers and improve plant health by enhancing the plant enzymatic antioxidant defense system.

The quantification of Soil Organic Carbon (SOC) pools and carbon farming potential of any land use and cropping systems are important indicators of productivity, profitability, and sustainability of that system. The objective of our present study was to evaluate the spatial and depth-wise distribution of SOC pools (active-C and passive-C) and carbon farming potential of major cropping and land use systems in Alfisols under southern agro climatic zone of Andhra Pradesh, India. We quantified active-C, passive-C pools, and SOC status in 19 different land use and cropping systems. The results indicated that SOC status and carbon farming potential were highest (P< 0.001) under forest land use (13.96 g kg-1 and 62.19 Mg ha-1) followed by mango orchards (> 15 years age) relatively less than 23.6%, and on par with sugarcane-vegetables 25.2%, and paddy-tomato 23.1 %. The lowest (P< 0.001) was recorded under rainfed groundnut 77.5%, followed by sugarcane-sugarcane 73.3%. The active-C pool was significantly (P< 0.001) higher in forest land use (8.79 g kg-1) followed by sugarcane-vegetables (8.3 g kg-1). The passive-C pool was higher (P< 0.001) under forest land use (7.98 g kg-1), on par with mango orchards> 15 years age (7.49 g kg-1) and followed by paddy-tomato (5.69 g kg-1) and sugarcane-paddy (5.12 g kg-1). The lowest (P<0.001) active and passive-C pools belonged to rainfed groundnut, current fallow lands, and sugarcane-sugarcane cropping systems. Of all the studied land use and cropping systems, carbon farming potential was higher under forest land use followed by mango orchards > 15 years age, sugarcane-vegetables and paddy-tomato cropping systems. The potential was medium under paddy-groundnut, groundnut-tomato/vegetables, tomato-vegetables, perennial fodder plantations, casuarina and eucalyptus plantations and sugarcane-paddy cropping systems, while it was low under paddy-paddy, groundnut-groundnut, flower crops and cultivable wastes and very low under rainfed groundnut, current fallow lands, and sugarcane-sugarcane cropping systems. Thus, the present study emphasizes on the carbon farming potential, which could act as an indicator for sustainability of the different land use and cropping systems under southern agro-climatic zone.

To investigate the response of soil microbial populations to different doses of glyphosate and sulfosulfuron, a factorial experiment based on a complete block design was conducted at Shiraz University, Iran. The factors included different herbicides and dose rates (glyphosate at 0, 540, 1,080, and 4,320 g ae ha-1 and sulfosulfuron at 0, 12.5, 25, and 50 g ai ha-1), and time of measurements (4, 15, 45, and 65 days after herbicides spray). Microbial respiration, microbial biomass carbon, metabolic quotient, dehydrogenase activity, and aerobic heterotrophic bacteria were measured in soil samples. The results showed that microbial respiration, microbial biomass carbon and metabolic quotient were highest for glyphosate 1,080 g ae ha-1 at 4 days after herbicide application. Dehydrogenase activity had a decreasing trend in all herbicide treatments in comparison with the control treatment in all measuring times, except 4 days after spraying. There was no significant difference in dehydrogenase activity between herbicide treatments. The effect of sulfosulfuron on microbial respiration and metabolic quotient was not significant, whereas time and its interaction with herbicide dose rate affected these two variables significantly. Generally, all the measured indices for sulfosulfuron and glyphosate treatments decreased with time after herbicide application. Sulfosulfuron at 50 g ha-1 and glyphosate at 4,320 g ha-1 had the lowest amounts of aerobic heterotrophic bacteria after 65 days, decreased by 23.7 and 50%, respectively compared with the control. Our results demonstrate that the effects of herbicides on soil microbial communities are strongly related to the herbicide dose and the time after herbicide spray. In conclusions, the herbicides at doses more than the recommended doses showed inhibitory effects on soil microbial communities in the alkaline soil, where the inhibitory effect was more at 4,320 g ae ha-1 glyphosate.

Optimum cropping pattern increases productivity where input resources are limited. An optimized cropping pattern was developed for a region in Moghan Plain, located in the northwestern Iran, to help water supplier in pre-season decision making on water and land allocation. AquaCrop simulation model was calibrated and executed for yield predictions for 11 different crops and 13 diverse soil types. Evaluation of AquaCrop model showed great robustness for a broad range of crops, even for the crops like canola and alfalfa that were undefined for the model. The precise generated crop water functions revealed the ideal conditions for water allocation by considering the impact of the existing limitation in monthly water availability on optimum cropping pattern without imposing any manipulation. Optimum cropping pattern based on water productivity (OCPWP) was identified by LINGO software. Integrating AquaCrop model and LINGO optimization problem solver created a Decision Support System (DSS) for technical analysis at the regional level. The created DSS is able to support the OCPWP in terms of the complex regional crop-mixture acreage. The ecological considerations introduced diverse winter crops to benefit from autumn precipitations. This strategy decreases irrigation requirement and saves some water for spring/summer high water-demanding crops like alfalfa and cotton, which generally enhances the system resiliency. The generated DSS revealed that 8,762 m3 water ha-1 was required for optimum cropping pattern, which is 8% lower than the maximum and 3% more than the average available water.

Climate change and low water use efficiency are the main reasons for reducing the water entering the Urmia Lake. Therefore, water use management via irrigation scheduling can be an effective strategy to restore this lake. This research was conducted to investigate the effect of climatic variables on water requirements, identify water-sensitive growth stages, and prepare irrigation scheduling guidelines for wheat, which is one of the main crops in the studied region. For this purpose, crop Evapotranspiration (ETc) and Net Irrigation Requirement (NIR) of wheat growth stages were estimated by computing the daily soil water balance of the root zone for a period of 32 years (1985-1986 to 2016-2017). Dividing wheat growth period into nine phenological stages was performed using Growing Degree Days (GDDs) and Zadoks scale. These stages included intervals of [Sowing-Emergence (StE)], [Emergence-Trifoliate (EtT)], [Trifoliate-Double ridge (TtD)], [Double ridge-Jointing (DtJ)], [Jointing-Booting (JtB)], [Booting-Heading (BtH)], [Heading-Anthesis (HtA)], [Anthesis-Maturity (AtM)] and [Maturity-Harvesting (MtHa)], whose mean ETc was estimated to be 2.30, 1.33, 1.03, 3.63, 4.69, 5.13, 6.53, 7.09 and 1.35 mm d-1, respectively. The mean ETc, Effective Precipitation (Eff. P) and NIR of wheat during its growth period were estimated to be 774, 349, and 425 mm, respectively. Results showed that wheat sensitivity to water stress is high from booting to maturity, is low from sowing to double ridge and from maturity to harvesting, and is moderate in other stages. Therefore, increasing the irrigation interval in the first three stages of growth and eliminating the end-stage irrigation are recommended for water saving.