Journal of Agricultural Science and Technology
Volume:22 Issue: 5, Sep 2020

Agriculture has always been a risky activity, and the first step in developing plans to face and overcome the risk is gleaning insight into the different types of risks and the risk factors. One of the risks faced in today’s agriculture sector is the production risk incurred by the inputs. The overarching goal of this research was to study the wheat production risk in Gorgan County, Iran, using the method proposed by using J-P (Just and Pope) approach. Data and information required for this research were obtained through stratified random sampling from 80 questionnaires completed in the 2015-2016 crop year. The estimation results suggested that with an increase in labor and farmers’ age, the production risk diminished, whereas the production risk escalated with an increase in the use of chemical fertilizers. Therefore, it is recommended to modify the usage pattern of this input to set the scene for the mitigation of the production risk of this crop in the region.

The development of economic valuation techniques and their potential applications to environmental assessment have important role in environmental economics. The objective of this study was to evaluate the conservation value of the Khabr National Park in Iran and peoplechr('39')s willingness to pay for preserving it. This park is one of the most important environmental resources of the country in terms of its flora and fauna in Iran. A contingent valuation method with a dichotomous choice questionnaire based on a logit model was applied to determine the conservation value and peoplechr('39')s willingness to pay for preserving the park. The required data was collected through completed questionnaires. Results indicated that the influence of the variables of bid, monthly income, gender, job and education level on households’ willingness to pay are statistically significant. Therefore, an increase in income, education level, and peoplechr('39')s expertise increases their willingness to pay, and an increase in bid decreases their willingness to pay. The Iranian householdschr('39') average monthly willingness to pay for this parkchr('39')s conservation value was estimated at 4,328.6 Rials. The results of the study indicated that the use of the public capacities to protect the natural resources and the environment is a step in financing and participation of people for better protection of the environment.

The present study aimed to analyze sugar beet farmers’ intention towards the acceptance of drip irrigation based on an extended version of Technology Acceptance Model (TAM). The main objectives of this study were introduction of the existing acceptance behavior models, comparison of these theories with a critical point of view, presentation of a theoretical framework based on TAM, and testing the possible relationships among variables. This descriptive-correlational research was conducted through a cross-sectional survey. The statistical population of the study was sugar beet growers of Miandoab District, Iran, of which 346 farmers were selected as the sample of the study using a multi-stage stratified random sampling method (N= 3326). The research instrument was a structured questionnaire, whose face, convergent, and discriminant validity were confirmed. Cronbachchr('39')s alpha and composite reliability coefficients were employed to examine the reliability of research tool (0.74< α< 0.93). The results revealed that the variables of attitude, perceived ease of use, and perceived usefulness have significant positive effects on behavioral intention towards accepting drip irrigation technology. Innovation features also have an indirect effect on behavioral intention. Furthermore, the results demonstrated that independent variables of extended version of TAM could account for 59.3% of variance of behavioral intention towards drip irrigation acceptance. The significant effect of attitude towards acceptance of drip irrigation in explaining farmerschr('39') intention towards acceptance of drip irrigation technologies implies that reinforcing farmerschr('39') attitudes will increase the likelihood of activating behavioral intention towards these new irrigation methods. In general, the results of this study contribute to the development of more integrated and comprehensive models in the field of farmerschr('39') acceptance behaviors. It also provides practitioners and policy makers of agriculture and water sectors with some useful insights regarding determinants and strategies of behavioral changes.

The lack of accountability of government organizations to address the needs of stakeholders and the private sector and the provision of low-quality services to clients has increased dissatisfaction with government services. Therefore, providing quality services is essential to increase satisfaction with government organizations. Extension services are one of the main components of sustainable agriculture development in Iran and are provided to farmers through the Agricultural Research, Education, and Extension Organization (AREEO). Considering the low level of farmerschr('39') satisfaction with extension services, development of a system for assessing farmerschr('39') satisfaction as a strategic project has been emphasized. This study was conducted to develop the components of farmerschr('39') satisfaction with extension services and determine the factors affecting their satisfaction, in 2019. In this study, the classic Delphi method was used during three rounds. The expert panel consisted of nine university faculty members, 14 faculty members of AREEO, and 19 headquarters extension experts (n= 42). Delphi results led to the selection of 37 components to assess the satisfaction of farmers with the extension services. These components were classified using the constant comparative method in four main factors. These factors include technical and professional features of the extension experts, service quality, perceived effectiveness, and policy, management, and planning.

Undoubtedly, investigation and recognition of individuals’ environmental behaviors are key prerequisites to resolve environmental problems, but empirical theory-based research on this topic is limited, particularly in developing countries. Accordingly, a mixed model based on the Theory of Planned Behavior (TPB), and the Norm Activation Model (NAM) was proposed by integrating rational and normative variables to explain Iranian villagers’ engagement in Pro-Environmental Behaviors (PEBs). A structured questionnaire was the main research instrument developed based on the combined TPB-NAM. The face validity of the questionnaire was determined by expert review. Additionally, the construct validity (including convergent and divergent validity) and the composite reliability were achieved by Confirmatory Factor Analysis (CFA). Data from a survey of 362 rural household heads of Tabriz County selected through a multistage probability sampling with three stages were used to assess empirically the research model and hypothetical relationships. The results of the Structural Equation Modeling (SEM) revealed that the accuracy and explanatory power of the combined TPB-NAM were superior to those of TPB and NAM. Additionally, Personal Norm (PN) was found to be the most salient predictor of villagers’ engagement in PEBs. Overall, the findings of this study contribute to theory building and development of a more comprehensive model in the field of PEB, and yield more insight into socio-psychological factors influencing villagers’ engagement in PEBs.

Persian Kurdish Horse constitutes a group of horses traditionally bred and used by Kurdish People who have lived and occupied todaychr('39')s western provinces of Iran for several millennia. Although very well-known for their unique characteristics, standards of this so-called breed of Iranian native horses have never been established. This study was designed to document and validate anecdotal information that has been passed along generations of Kurdish Horse breeders about unique physical characteristics and performances of this native horse breed of Iran. The first author traveled to provinces with larger numbers of Kurdish Horses in Iran and conducted personal interviews with 114 of well-known Kurdish Horse breeders. Questioners were completed. Then, the degree of concordance on various physical and performance characteristics of Kurdish Horses that were anecdotally considered as more important traits to identify and define Kurdish Horses was established. Based on such validated data, characteristics with a higher degree of agreement were formatted into a proposed “Breed Type and Standards” for Iranian Kurdish Horses.

This study evaluated the effect of pawpaw, black cumin, and mustard seed meals (PSM, BSM, and MSM, respectively) supplementation on broiler chickens’ performance, gut microflora, and gut morphology. Two basal diets were formulated for the starter and grower phases and divided into five portions. Portion one (Diet 1), the negative control, contained no supplementation, portion two (Diet 2), was supplemented with 0.11 g kg-1 oxytetracycline. The third (Diet 3), the forth (Diet 4) and the fifth portions (Diet 5) were supplemented with 15 g kg-1 PSM, MSM and BSM, respectively. Three-hundred 1-day old Arbor Acres broiler chicks were randomly distributed into five treatments (10 chicks/replicate; 60 chicks/treatment) in a completely randomized design. The performance characteristics of the birds were determined on 7 days interval. On day 42, three birds per replicate were sacrificed for the determination of the carcass traits and relative internal organs weights. At the grower phase and overall, the Body Weight Gain (BWG) of broiler chickens fed Diet 3 was similar (P> 0.05) to those fed Diet 4, but significantly (P< 0.05) higher than the broiler chickens fed the rest of the diets. The liver, pancreas and gizzard relative weights were affected (P< 0.05) by the treatment. On day 42, higher (P< 0.05) Lactic Acid-producing Bacteria (LAB) count was recorded in birds fed Diet 2. In the jejunum, the villi heights and crypt depths were higher (P<0.05) in bird fed Diets 1, 2, and 3. Supplementation of the broiler diets with 15 g kg-1 of PSM, BSM and MSM enhanced the body weight of broiler chicken.

In this study,  the antimicrobial effect of  Coriandrum sativum L. leaves against 30 different foodborne microorganisms, including 20  bacteria, 7 fungi and, 3 yeast species, and some microbiological properties of yoghurt produced with  lyophilised Coriandrum sativum L. at three different level (0.1%, 0.2% and 0.3%) and sotored at 4°C for 21 days were examined. Ethanol extract of the fresh plant extracts showed antimicrobial activity against only 9 bacteria and 1 yeast with different zone changing from 8 to 12 mm, but had no effect on fungi used in the study. On the other hand, the addition of Coriandrum sativum L. inhibited the yeast and mould growt in yoğurt samples throught the 21 days of storage. Generally, the ratio of Coriandrum sativum L. increased the number of Lactobacillus bulgaricus, but decreased the number of Streptococcus thermophilus. However it was not important statistically (p<0.05). The results indicated that Coriandrum sativum L. can be used as a good source of preventing the growt of yeast and mould which effects the storage life of yoghurt.

Milk fat, one of the expensive fatty matters, might be sometimes adulterated with other edible fats, particularly palm oil or its fractions, which can be a major problem for the dairy industry, especially in Iran. The aim of this study was to investigate the adulteration of milk fat based on some minor components present in unsaponifiable matters, namely, sterols and squalene. Different concentrations of palm oil and its fractions (0, 1, 2, 5, 10, 20, 50, and 100%) were added to pure milk fat. Sterol and squalene contents were determined by the application of GC and HPLC, respectively. The experimental data showed that β-sitosterol was the main phytosterol in palm oils and it could be a good indicator for detection of adulteration by palm oil as low as 5%. The result also indicated that squalene was not identified in milk fat, so, it can be considered as a good indicator to show the presence of palm oil as low as 1%. According to the results, it might be concluded that sterols and squalene could be used as important indicators to find the presence of palm oil and its fractions in milk fat.

Neonicotinoid pesticides such as imidacloprid and thiacloprid are agonists of nicotinic Acetylcholine Receptors (nAChRs). This chemical group is commonly used in controlling sucking pests such as cotton whitefly, B. tabaci, one of the most serious and destructive pests of agricultural crops worldwide. Bioassays were performed using a leaf dip method and Ahvaz population with the lowest LC50 value (24.40 mg ai L-1) was considered as the susceptible population. LC50 values of Karaj, Isfahan, Kashan, Gorgan and Minab populations were estimated as 189.81, 136.91, 106.95, 141.09, and 68.31 mg ai L-1, respectively. Low Resistance Ratios (RR) to imidacloprid were observed in the tested populations (RR values< 10). The piperonylbutoxide (PBO) and TriPhenyl Phosphate (TPP) showed the highest synergistic ratios of 1.99 and 2.42 in the population of Kashan, respectively, but DiEthyl Maleate (DEM) did not show a high synergistic ratio. The activity of cytochrome P450-dependent monooxygenase (P450s), CarboxylEsterase (CarEs) and Dlutathione S-Transferases (GST) were measured. There was an increase in the activity of P450s up to 3-fold in the Gorgan population and CarE activity in Kashan population up to 2-fold in comparison to the susceptible population. Based on the results, P450s and CarEs are possibly the enzyme systems responsible for imidacloprid resistance in the tested populations of B. tabaci.

The importance of the diamondback moth, Plutella xylostella (L.), has dramatically risen mainly due to the overuse of broad-spectrum insecticides, which has resulted in increased selection for pesticide resistance, destruction of natural enemies, and pest resurgence. These issues accompanied by increasing insecticide residue on crops have created an urgent need for more sustainable strategies for P. xylostella management. The present study examined the efficacy of extracts from different parts of the jimsonweed, Datura stramonium L., as larvicide and oviposition deterrent on P. xylostella larvae and adults, respectively. Bioassays revealed higher toxicity (LC50 and LC90) of flower (82.3 and 1,475.4 mg L-1), seed (146.8 and 4,828.7 mg L-1) and root (165.3 and 3,493.8 mg L-1) extracts of D. stramonium compared with leaf (526.6 and 29,352.1 mg L-1) and stem (841.4 and 136,248.1 mg L-1) extracts. In addition, flower extract showed the greatest toxicity between the extracts based on LC50 dose ratio (0.561, 0.498, 0.156 and 0.098) and LC90 dose ratio (0.306, 0.422, 0.050 and 0.011) when compared with seed, root, leaf and stem extract, respectively. Furthermore, oviposition deterrence tests using sublethal doses exhibited that the highest oviposition inhibition was provoked by flower extract of D. stramonium (63.0%) compared with root (46.0%), seed (43.8%), stem (33.7%), and leaf (28.3%) extracts. Results indicated that jimsonweed extracts could be used as an effective pesticide and oviposition deterrent against P. xylostella. Possibilities for application of D. stramonium extracts in pest management and for developing a botanical insecticide or an oviposition deterrent in context of sustainable pest management are discussed.

To identify the important features of triticale that contribute to improving grain and biomass Water Use Efficiency (WUEg and WUEb, respectively), grain yield, and Nitrogen (N) remobilization, a 2-year side-by-side experiment was carried out on triticale with different nitrogen sources and water regimes, in a typical Mediterranean environment of Iran. There were two levels of water regimes: Normal Irrigation (IRN) and irrigation cut off after anthesis stage (IRMD). Rain-fed treatment (IR0) was included in the second year. Four N sources including Azospirillum brasilense (Bio), Azospirillum brasilense+75 kg N ha-1 as urea (Bio+N75), 150 kg N ha-1 as urea (N150), and control unfertilized (N0) plots were used. This study showed that the highest grain yield (6,258 kg ha-1) was achieved by chemical N fertilizer application (N150) under IRN. In contrast, the application of Bio+N75 resulted in the highest grain yield as compared with the other N sources under IRMD (4,409 kg ha-1) and IR0 (2,960 kg ha-1) conditions. Water stress significantly increased WUEb at all N sources. However, WUEg slightly increased by IRMD and then sharply decreased by IR0 in all N sources, except N150 plots, where WUEg drastically decreased by water stress imposed by IRMD and IR0. The Bio+N75 treatment had the highest N remobilization. Although N remobilization was not affected by IRMD in dryer year, it increased by IRMD (8.4%) in the relatively wet year. Totally, for a more sustainable farming system in arid Mediterranean conditions, integration of biofertilizer and chemical N fertilizer could be successfully used for increasing grain yield, WUE, and N remobilization of triticale, especially under deficit irrigation regimes.

This research studied changes in antioxidant enzymes activity, Total Soluble Proteins (TSPs), Malondialdehyde (MDA), and proline content in the leaves of three olive (Olea europaea L.) cultivars (Amphisis, Gorgan, and Manzanilla) at five different dates, and investigated their relationship with cold tolerance. The results revealed that cold-acclimation dramatically increased cold tolerance. Furthermore, antioxidant enzymes activity, MDA, TSP, and proline content increased throughout the acclimation stage, whereas they declined in the de-acclimation stage. The ascorbate peroxidase, catalase, peroxidase, and superoxide dismutase activities in the leaves tissues correlated with the alterations in cold tolerance. Higher TSP, greater antioxidant enzyme activities, and more proline content together with lower MDA content in Amphisis cultivar led to relative improvement in cold tolerance capacity of this cultivar. Our results showed antioxidant enzymes activities, TSP and proline content could be useful indices to screen cold tolerance in olive cultivars.

The genus Nepeta is one of the largest genera in the Lamiaceae family, and Iran is one of the main centers of origin of this genus. The genetic diversity estimation of the genus Nepeta germplasm provides a basis for future biodiversity conservation efforts and also for the selection of high-productive genotype(s) for the field production improvement. In this work, eleven RAPD primers with suitable banding pattern and prominent polymorphism were used for the estimation of infraspecific genetic diversity of N. kotschyi based on 21 populations. The study included 19 and 2 populations belonging to var. persica and var. kotschyi, respectively. Eleven primers amplified totally 225 scorable RAPD loci, 204 of which were polymorphic. The average number of bands per primer was 20.5, 18.5 of which were polymorphic. Primers OPF 05, OPB 15, OPT 14, OPO 07, and OPF 14 were the most powerful for the detection of the genetic diversity across the samples. Cluster analysis showed six genotypic groups. N. kotschyi var. kotschyi populations were placed in a group separated from the samples belonging to N. kotschyi var. persica. The same analysis showed that the genetic diversity pattern corresponds to the geographical distribution of the populations. Of the total variation in the studied germplasm, 32% was related to inter-populations and 68% to intra-populations variation. The results indicated the high potential of RAPD markers to resolve the status of the studied genotypes in regard to inter- and intra-populations diversity and to diversify N. kotschyi varieties previously resolved by morphometric methods.

The effects of abiotic stresses on medicinal plants metabolism are well known, but how plants respond to the interaction of these stressors is little understood. Therefore, the current experiment was aimed to investigate changes in growth and concentration of various primary and secondary metabolites of A. vera grown under water deficit and different light intensity conditions. A split-plot in time research was laid out in a randomized complete block design with four replications in a research greenhouse. The factorial combination of four irrigation regimes (irrigation after depleting 20%, 40%, 60%, and 80% of soil water content) and three light intensities (50%, 75%, and 100% of sunlight) were considered as the main factors. Sampling time was considered as sub factor. The results showed that the highest leaf, gel, and peel fresh weights were observed when the plants were subjected to low light intensity and irrigation was done after depleting 20% soil water moisture. Plants developed under full sunlight produced more pups (4.30, 3, and 3.75 per plant, 90, 180, and 270 days, respectively) and leaves (14.25, 18, and 21.25 per plant, 90, 180 and 270 days, respectively) and showed the higher fresh (165.75 g per plant) and dry root (37.60 g per plant) weight. These traits decreased with increasing water deficit severity during all the sampling times. Glucose (79.30 mg g DW− 1, 270 days), fructose (233.50 mg g DW− 1, 270 days), aloin (27.68%, 90 days), proline (2.07 mg [g FW]-1, 90 days) and phosphoenolpyruvate carboxylase (PEP-Case) (0.463 mmol NADH/g prot*min, 90 days) increased with increasing light intensity and water deficit severity during all the sampling times. Although high light intensity and water deficit led to yield and growth reduction, concentration of various primary and secondary metabolites increased. The results suggest that reduction in light intensity mitigates adverse effects of water deficit by inducing primary and secondary metabolites changes. It can be considered as an acclimation mechanism under water deficit conditions to avoid yield loss in A. vera production.

There are contrasting reports on the relationship between production and drought tolerance of crops with root structure. The presented research aimed to evaluate grain yield and root-related traits (in two depths) under optimal and drought stress conditions and assess the effect of root-related traits on grain yield and drought tolerance in cultivated barley (Hordeum vulgare ssp. vulgare) and wild barley (H. vulgare ssp. spontaneum). In this experiment, 30 barley genotypes were evaluated in pot culture experiment for root traits and in the field for grain yield and drought tolerance for two consecutive years. The results indicated that the genotypes with high root dry weight, area, volume and length and root to shoot ratio in depth 0-30 cm have also high value of these root traits under the depth of 30-60 cm. In this study, the root system size increased when the plants imposed to drought stress, and the level of increase was higher in the deeper soil layer. The wild barley genotypes Hsp06, Hsp74 and Hsp79 had high averages of the root dry weight, area, volume and length under both water environments. The results of farm experiment indicated that the genotypes from cultivated barley mostly have higher yield potential; however, the wild barley genotypes mainly have more yield stability under drought stress environment. The wild barley Hsp71 was identified with both high yield potential and stability under drought stress. Root dry weight and root to shoot ratio were negatively correlated with grain yield under control conditions. Under stress condition, root area, length and volume were positively correlated with yield stability index. Results indicated that the vigorous root system is not necessarily related to higher grain yield in barley; however, higher yield stability under stress environment is highly related.

Investigation for developing natural plant protection products as an alternative to synthetic fungicides has become important regarding the environmental impact. In this study, the chemical composition and the antifungal activity of five Moroccan aromatic plants, namely, oregano (Origanum compactum), thyme (Thymus vulgaris), Eucalyptus (Eucalyptus camaldulensis), mint (Mentha pulegium L) and myrtle (Myrtus communis) was explored for controlling Ascochyta rabiei, in vitro. The pathogen is a seed-borne causal agent of Ascochyta blight and it is considered the most economically damaging disease of chickpea. The radial growth of A. rabiei was completely inhibited by oregano, mint, thyme and myrtle at low concentrations (0.15-5 µL mL-1). The most important effect was obtained with oregano (Minimum Inhibitory Concentration, MIC- 0.15 µL mL-1), followed by Thyme (MIC- 0.5 µL mL-1). The phytotoxicity test of these essential oils on chickpea germination showed that oregano and Thyme oils do not have phytotoxic effects at MIC concentrations, whereas mint and myrtle oils can have an effect on reducing germination percentage of chickpea seeds. The chemical composition of tested essential oils was analyzed using Gas Chromatography-Mass Spectrometry (GC-MS analysis). The analysis revealed the dominance of two compounds (Thymol and Carvacrol) in the most effective oils and can represent the principal active ingredient in the pathogen control. Therefore, the essential oils of oregano and Thyme or their major compounds could be investigated for seed or foliar treatment of chickpea against Ascochyta blight infection.

Two endophytic fungi, namely, Curvularia lunata and Nigrospora sphaerica, were isolated from Melia azedarach, an exotic tree introduced in Egypt from Asia. The fungal endophytes were identified by microscopic examination and molecular identification of nucleotide sequence by DNA sequencing of the purified PCR product. Their antagonistic activities against phytopathogenic fungi and their ability to produce important growth hormone and providing some necessary nutrients for plant growth were also evaluated. Both endophytes exhibited antagonistic activities: C. lunata caused 56% and 50% growth inhibition of Alternaria solani and Fusarium oxysporum, while N. sphaerica suppressed both pathogenic fungi by 63.4% and 56.6%, respectively. N. sphaerica was able to dissolve insoluble phosphorus, produce ammonia, and secrete 40 µg mL-1 of IAA. In contrast, C. lunata failed to dissolve phosphorus, secreted less amount of IAA (3 µg mL-1), but produced ammonia. A greenhouse pot experiment was conducted using phosphorus deficient soil to find out the ability of both endophytes to improve growth of tomato plants. N. sphaerica significantly increased shoot fresh weight by 13% and 22% over C. lunata and the control, respectively. Concerning the nutritional status of tomato plants, both endophytes led to significant increase in nitrogen concentration in shoots when applying 50% of the recommended mineral fertilizer. N. sphaerica enhanced phosphorus concentration in shoots by 13% over the control. Finally, the antifungal activities of both endophytes against F. oxysporum in tomato plants were tested under glasshouse conditions. N. sphaerica was more potent than C. lunata in suppressing 40% of F. oxysporum infection and had positive impact on tomato plant growth. Our study results highlight the potential use of N. sphaerica endophytic fungi as plant biofertilizers and bio-control agent under glasshouse conditions.

In this study, to determine the optimum crop pattern of Kermanshah plain, Iran, a dynamic model was developed in Vensim PRO x32 software to simulate the actual situation in the region. Stochastic simulation of time series method was used to predict the values of climate parameters in the future. After ensuring the performance of the dynamic model as well as time series model, optimization process of crop pattern was performed using the existing optimization tool in Vensim PRO x32 software in addition to multi objective mathematical programming approach by Powell method in three different scenarios. The objective functions included maximizing the economic benefit for farmers and minimizing the extracted water from aquifer. The results showed that ratio of the gained benefit to the amount of water extracted from the wells in optimized conditions was always higher than the current conditions. The value of this ratio for the three scenarios was 1.23, 0.89, and 0.94, respectively, which in all three scenarios are higher than the current value (0.68). The results showed that according to a case in which variations in the crop coefficients of all crops are possible, in order to optimize the crop pattern,  the area allocated to wheat, barley, grain and forage maize, tomato, clover, and onion must be decreased in the current crop pattern. Furthermore, the results of optimization indicated an increase in the area under the cultivation of saffron, rose, greenhouse, medicinal plants, and olive, compared to the current conditions.