JOURNAL OF AGRICULTURAL SCIENCE AND TECHNOLOGY (JAST)
Year:2020 | Volume:22 | Issue:4|Papers Count:19

At the colleges of agriculture in Iran, lecture is used as a dominated teaching method. Team learning is one of the most commonly used educational methods in the present erea. The aim of this study was to compare the Team Member Teaching Design (TMTD) and the regular lecture method on the academic achievement and teamwork behavior of agricultural students. A within-subject design was followed for two courses in which students first attended a series of lectures and then participated in team teaching. Differences between lecture and team teaching methods were examined for their academic achievement and teamwork. The study samples were taken of Agricultural Extension and Education Department of the University of Tehran during the academic year of 2017-2018. The mean scores of academic achievement and the teamwork behavior of students were compared. In compared coursess, the effect of TMTD method on the academic achievement of students was shown. The results of means comparison tests indicated a significant difference between the two methods of teaching in the field of academic achievement and the strengthening of the teamwork behavior of students. The paper further discusses team method implementation and its implication for teaching and proffers the way forward for an effective use of teaching methods for better results in the classroom teaching and learning process.

The climate is changing and agriculture sector is heavily dependent on climatic changes. Considering the key role of perception and its impact on behavior and given the importance of climate changes in today’ s world, the present research was conducted with the aim of investigating the factors affecting perception and adaptation behavior of farmers in response to climatic changes in Hamedan, Iran. For this aim, first, the factors affecting the farmers’ perception and adaptation behavior were extracted from literature review. Then, a questionnaire was developed, and to determine its validity, the questionnaire was examined by a panel of experts. Further, to measure the reliability of the research instrument, a pilot test was conducted. The statistical population of the research consisted of 115, 160 farmers in Hamedan Province and the sample size based on Krejcie and Morgan table was determined as n= 384 farmers. Then, a stratified random sampling with proportional allocation was used. The findings indicated that among the studied variables, knowledge, perception, and belief with path coefficients of, respectively, 0. 53, 0. 32, and 0. 18 had the maximum impact on the adaptation behavior, while the maximum impact on perception belonged to belief and knowledge with path coefficients of, respectively, 0. 56 and 0. 35. According to the results, knowledge, which had the highest contribution in explaining behavior, was not seen in the Arbuckle et al. (2015) model. Therefore, to make it easier for the farmers to communicate and facilitate the transfer of information on climate change, establishment of community-based organizations is suggested. In addition, by enhancing the level of farmers awareness about climate-smart agriculture, it is possible to take major steps to improve their adaptation to climate changes.

Conservation of environment as one of the main pillars of human life requires the attention and effort of all people, especially women, and the prerequisite for that is the Environmental Literacy (EL). The purpose of this mixed-method research was to assess rural women's EL level, and identify appropriate methods of EL extension among them. Statistical population of the study consisted of 203, 504 rural women (15-64 ages), of whom 384 women were selected as sample using modified stratified random sampling technique. In order to gather the information, a questionnaire was developed including components of environmental attitudes, concerns, knowledge, skills, and behavior. Validity of questionnaire was confirmed by a panel of expert, and its reliability was confirmed by Cronbach’ s alpha (0. 86– 0. 93). In the qualitative section, the study population consisted of experts in agriculture extension, environment and natural resources, as well as rural women. Samples were selected using purposeful sampling and snowball technique. Results of quantitative section showed that the level of EL of rural women was moderate (M= 61. 427, SD= 8. 003) and means of environmental knowledge (M= 10. 292, SD= 3. 293) and concern (M= 11. 926, SD= 2. 328) were lower than other dimensions. MANOVA analysis also revealed that there were significant differences in level of EL of rural women among townships of Kermanshah Province with different degrees of agricultural development. Rural women in more developed regions had higher environmental knowledge and skills, but their environmental behavior was similar to underdeveloped and developing regions. The results of the qualitative section also indicated that EL extension methods of women in the villages of different regions were almost the same, but the women from the developed villages had higher tendency to participatory extension methods Results from this study could contribute to improvement of environmental program in order to promote EL across the society.

Human well-being is one of the main goals of sustainable rural development. Indeed, human well-being demonstrates rural societies’ quality of life. This concept consists of objective and subjective well-being dimensions. Although it is assumed that objective well-being is rationally related to subjective well-being, this relationship has not been fully confirmed in past studies. Three main reasons including the geographical level of assessment, the type of data used, and different epistemological perspectives have separated objective well-being assessment from the subjective one. We used the same geographical level, type of data used, as well as epistemological perspective in order to evaluate the relationship between objective well-being and subjective well-being among rice farmers. Using a questionnaire, a survey was carried out among 384 rice farmers (Response rate= 92. 3%) in the main rice cultivation areas in Iran. The study sample was chosen by a two-stages cluster random sampling technique. Face to face personal interview was also used as the form of data collection. The results of structural equation modeling illustrated that farmers’ perception of economic, social, and environmental well-being as objective well-being domains significantly explained their subjective well-being constructs including happiness as well as life satisfaction. In fact, life satisfaction and happiness would be changed once farmers mentally perceive objective well-being domains. Therefore, objective well-being indicators can affect subjective well-being constructs, including life satisfaction and happiness, if they are assessed based on farmers’ self-evaluation.

The aim of this study was to determine the differences in digit sizes from both pelvic limbs of 169 dairy cows of different genetic groups (Holstein, Jersey, Brown Swiss, and Jersolando), in lactating and non-lactating conditions, and their relation with diseases. Images were taken from the plantar view of the lateral and medial digits, and the length and width of the sole and bulb were then measured. Variables were discarded and factors for analysis were defined. Data were defined according to the highest coefficients and used to discriminate genetic groups and their association with indexes of foot diseases and productive performance. The Chi-square test showed that higher involvement occurred in lactating cows and in the right pelvic limb. Differences among all genetic groups were observed regarding the variables body weight, productive longevity, incidence of foot diseases, and generated factors. The Jersey breed was isolated from the other genetic groups because it presented lower coefficients for all variables; Holstein and Brown Swiss presented the highest morphometric measures of the digits, a higher body weight, and productive longevity, and higher rates of foot diseases. The Jersolando presented intermediate values between those of the two breeds from which it originated. The susceptibility to foot diseases is associated with breed, lactational stage, body weight, and with the morphometric parameters of the digits.

The biological procedure used to determine the nitrogen-corrected True Metabolizable Energy (TMEn) value of feed ingredient is costly and time consuming. Therefore, it is necessary to find an alternative method to accurately estimate the TMEn content. In this study, 2 methods of Multiple Linear Regression (MLR) and Artificial Neural Network (ANN) were developed to describe the TMEn (Kcal kg-1 DM) value on a Dry Matter (DM) basis of Wheat Bran (WB) samples given their chemical composition of Ether Extract (EE), ash, Crude Protein (CP) and Crude Fiber (CF) contents (all used as % of DM). A data set containing 100 WB samples were used to determine chemical composition and TMEn. Accuracy and precision of the developed models were evaluated given their produced prediction values. The results revealed that the developed ANN model [R2= 0. 90; Root Mean Square Error (RMSE)= 64. 07 Kcal kg-1 DM for training set; and R2= 0. 89; RMSE= 82. 69 Kcal kg-1 DM for testing set] produced relatively better prediction values of TMEn in WB than those produced by conventional MLR [R2= 0. 81; RMSE= 86. 76 Kcal kg-1 DM for training set; and R2= 0. 84; RMSE= 86. 61 Kcal kg-1 DM for testing set]. The developed ANN model may be considered as a promising tool for modeling the relationship between chemical composition and energy of WB samples. To provide the users with an easy and rapid tool, an Excel® calculator, namely, ANN_WB_ME_Poultry, was created to predict the TMEn values in WB sample given its chemical composition and using the developed ANN model.

In this simulation study, Mate Allocation (MA) strategy using combined genomicpedigree information was compared with Random Mating (RM) aiming at controlling the level of inbreeding (Δ F) with minimum impacts on the amounts of Genetic Gain (Δ G) in poultry breeding programs. Five equally-sized subpopulations of chickens (P1 to P5) were simulated. A genome encompassing five chromosomes involving 15, 000 bi-allelic markers was defined for each bird. Potentially, 500 QTL impacted a trait, which had a heritability of 0. 1. Only pedigree information was assumed to be available in P1 while the percent of genotyped birds were 10% in P2, 20% in P3, and 50% in P4 and P5. Estimated Breeding Values (EBVs) were computed using the traditional approach (PBLUP) and the Single-Step method (SSGBLUP). In P5, early predictions were applied to estimate GEBVs. Comparisons were made based on the reductions in Δ F and changes in Δ G between two mating scenarios and two evaluation methods within and across subpopulations, respectively. After seven generations, MA resulted in 20 to 30% less Δ F within subpopulations compared with RM with negligible impacts on Δ G. Furthermore, in both mating scenarios, SSGBLUP brought about 11 to 61% less Δ F compared to PBLUP across subpopulations. Results indicated that the benefits of using combined genomicpedigree relationships could be more than improving the accuracy of EBVs through the SSGBLUP as they can also be used in mating designs to restrict Δ F with a minimum impact on Δ G. Also, this study verified that SSGBLUP could bring about lower Δ F compared with PBLUP.

The common cutworm, Agrotis segetum, is a serious soil pest of many vegetable and field crops all over the world. Morphological identification of Agrotis species is predominantly performed on adults due to the deficiency of adequate identification keys for immature stages. In international trade, the immature life stages are frequently being intercepted at point of inspection, challenging the possibilities of morphological identification. To realize a rapid and reliable identification for all stages of A. segetum, a TaqMan real-time Polymerase Chain Reaction (PCR) was developed based on the mitochondrial Cytochrome Oxidase I (COI) gene. All specimens of A. segetum (including various life stages) were detected and no cross-reactivity was observed with 5 non-target Agrotis species in the specificity tests. The tests showed to be repeatable, reproducible, and robust. The assay performed equally well with crushed insects and purified DNA, so, the efficiency was added by removing DNA extraction step. The method has proven to be suitable tools for routine identification of all life stages of A. segetum considering the speed, specificity, as well as sensitivity of the assay.

Cold plasma is a novel non-thermal technology for the food and packaging industry. In this study, the effects of argon glow discharge plasma on the mechanical properties, surface topography, chemical composition, film hydrophilicity, film solubility, and barrier properties of the starch films were examined. Plasma treatment improved Tensile Strength (TS) of the starch film. In contrast to TS, elongation at the break of the plasmatreated films remained unchanged. The surface roughness of starch film increased after plasma treatment. An apparent increase in the surface hydrophilicity was observed due to formation of oxygen-containing polar groups. FTIR analysis confirmed the increase in the oxygen containing groups in plasma-treated starch film. However, film surface hydrophilicity caused no significant change in the solubility of films. No significant difference was found in the barrier properties of the starch films. The evaluation of films modifications by glow discharge plasma will contribute to in-package decontamination studies of food products by plasma.

This study was conducted to investigate the response of four barley cultivars (Reyhan03, Yousef, Afzal, and Khatam) to salinity stress at 0 (control), 100, 200 and 300 mM levels as a factorial experiment, within the randomized complete block design in three replications in a greenhouse, using the Hoagland solution. The physiological and biochemical properties including dry weight and RWC, photosynthesis pigments, K+/Na+, osmotic adjustments (soluble sugars, glycine betaine, proline), hydrogen peroxide and antioxidants enzymes (catalase and peroxidase) in root and shoot of barley cultivars were evaluated in saline and non-saline conditions. To determine the relationship between growth performance and the physiological and biochemical properties, the correlation between the properties and causality analysis was examined. Results obtained from comparing the mean among the treatment combinations showed that the salinity stress reduced the dry weight, photosynthesis pigments, and K+/Na+, while it increased the soluble sugars, glycine betaine, proline, H2O2, catalase and peroxidase in the root and shoot of barley cultivars. Correlation analysis indicated that potassium in the shoot had the most positive and significant correlation coefficient (r= 0. 86) with the dry matter of shoot. The stepwise regression analysis showed that the root dry weight, catalase of root and shoot, H2O2 of shoot and K+/Na+ of shoot contributed to the performance. Causality analysis revealed that the root dry weight, K+/Na+ of shoot, and catalase of shoot were highly important as they had a direct positive and significant impacts on the performance of shoot dry matter.

The objective of this study was to investigate the physiological responses and biological yield of black cumin (Nigella sativa L. ) to nitroxin biofertilizer and chemical nitrogen fertilizer in the form of urea under different irrigation regimes. A split plot experiment was conducted on the basis of randomized complete block design with three replications. The main factor included four irrigation regimes (i. e., weekly from emergence to harvest and withholding from blooming to maturity, flowering to maturity, and the start of seed formation to maturity) and sub-factor included five levels (i. e., no application of fertilizers, 80 kg N ha-1, 40 kg N ha-1, combination of 40 kg N ha-1+nitroxin biofertilizers, and nitroxin biofertilizer). Application of 80 kg N ha-1 under full irrigation and the combined application of 40 kg N ha-1 and nitroxin under all withholding irrigations produced the highest glycinebetaine, polyphenol oxidase and catalase enzyme, total chlorophyll, and biological yield. Withholding irrigation from the blooming stage and also the application of 80 kg N ha-1 resulted in the highest concentration of malondialdehyde. In combined application of 40 kg N ha-1 and nitroxin, polyphenol oxidase, proline, and soluble protein were at the highest levels. Generally, the combined application of 40 kg N ha-1 and nitroxin increased the activity of the antioxidant enzymes and the compatible osmolites accumulation under all withholding irrigation treatments and thus decreased the negative effects of drought stress on black cumin, resulting in increased biological yield.

The aim of the present study was to determine the effects of seed priming with 24-Epibrassinolide (EBR) (10-8 M) on growth, biochemical, and molecular characteristics of Linum usitatissimum L. seedlings under Polyethylene Glycol (PEG) induced drought stress conditions. Imposition of flax seedlings to 6, 12, and 18% PEG declined germination rate, shoot length, root length, fresh and dry weights, and significantly increased phenolic content and PAL (Phenylalanine Ammonia Lyase) enzymatic activity while lowering flavonoid content. Application of EBR significantly increased the germination rate, shoot and root lengths, dry weight, fresh weight, and anthocyanin content whereas reduced phenolic content. At the molecular level, CHS (Chalcone Synthase) and PAL (Phenylalanine Ammonia Lyase) transcripts were upregulated under drought stress and even more expressed by application of EBR. In conclusion, EBR presowing seed priming considerably alleviated damages caused by drought stress and improved growth parameters in Linum usitatissimum L. seedlings.

Aril Browning (AB) is a physiological disorder in pomegranate fruit that critically decreases fruit quality and market acceptability. This experiment was carried out in order to explore the effective pomegranate fruit quality traits associated with the AB disorder and select the suitable resistant cultivar and genotypes. Pomegranate physicochemical fruit quality attributes were assessed on 238 mature pomegranate genotypes and their correlations with the AB disorder were monitored. About 14. 7% of the studied genotypes showed resistance to the AB disorder, but 68. 14% showed moderate to severely susceptibility to the incidence. The intensity of the AB disorder symptoms in pomegranate genotypes was strongly correlated with physico-chemical fruit attributes. There was a negative significant correlation between the intensity of AB disorder and fruit size, fruit volume, fruit acidity, and total soluble solids (TSS) to titratable acidity (TA) content. . Among the studied fruit traits, stepwise regression analysis showed that fruit acidity (pH), aril color, fruit volume, and TA content were efficient traits for screening of pomegranate genotypes in relation to the AB disorder.

To extend the genetic base of Iranian tomato germplasm, 93 landraces were collected from the northwest of Iran and East Anatolian of Turkey, along with three commercial cultivars, and their genetic structure were studied using 39 SSR primers. Thirty-five polymorphic SSR loci generated a total of 118 alleles in the studied germplasm. Number of alleles per locus and effective number of alleles averaged 3. 37 and 2. 47, respectively. Expected heterozygosity of SSRs varied from 0. 227 (TMS24) to 0. 773 (LEta016), averaged 0. 558. The mean number of alleles per genomic-SSRs (3. 61) was more than that of ESTSSRs (2. 66). Cluster analysis using Neighbour Joining (NJ) method placed 96 tomato genotypes in eight groups. Little congruence was found between NJ dendrogram and geographical distances. Genetic structure analysis of the germplasm using Bayesian method revealed two sub-populations and separated cherry tomatoes from the other landraces and commercial cultivars. Out of the 21 morphological characters, significant (P≤ 0. 05) marker-trait associations were found for 18 characters. Each of SSR loci TC11, TC948, and Tom236-237 was associated with three characters. The genetic variability, structure, and markers associated with the studied traits in the current study can be used for planning tomato breeding programs and future studies.

The objective of the present study was to evaluate antifungal activities of 18 native Bacillus strains against Phytophthora drechsleri Tucker in saline and normal conditions. Besides, the effect of exogenously provided bacterial osmoprotectants (ectoines) on biocontrol activity of three selected Bacillus strains with the highest biocontrol activity and three antagonistic bacteria from two different genera (Pseudomonas fluorescens, Streptomyces rimosus and Streptomyces monomycini) was studied in normal and saline conditions. To reveal the effects of ectoines on the mode of action of antagonism, amylase, protease, lipase, cellulase, chitinase and Hydrogen Cyanide (HCN) activity, biofilm formation and intracellular ectoines of the selected strain (Bacillus amyloliquefaciens UTB96) were investigated in normal and saline conditions. Phylogenetic tree based on the 16S rRNA gene sequences divided Bacillus strains into two groups: one clade included strains that were tolerant up to 5% and the second 13% NaCl. Salt (0. 3M NaCl) reduced the antagonistic activity of selected Bacillus strains (10. 39-38. 34%) and P. fluorescens (25. 77%) compared to the control. Exogenously provided ectoines adjusted the biocontrol drop caused by NaCl in Bacillus and Pseudomonas strains and increased biocontrol activity of S. monomycini. Salinity (0. 3M NaCl) reduced amylase activity of UTB96 up to 17% and ectoines prevented the reduction. Salt also decreased biofilm formation to about 3-fold and ectoines significantly ameliorated the reduction. The HPLC assay indicated that UTB96 accumulated ectoine and hydroxyectoine 0. 16 and 0. 10 μ g/mg cell dry weight, respectively. Exogenously added ectoine and hydroxyectoine led to a significant increase in UTB96 intracellular ectoines concentrations.

The root-knot nematode, Meloidogyne incognita, is parasitic to the plants and greatly damages the root of many vegetables. The current in-Planta study was designed to explore the nematicidal properties of several botanicals (neem oil, garlic oil, castor oil, extracts of Tagetes patula and Datura inoxia at a standard dose of 2. 0%) at District Peshawar, Pakistan. Tomato (cv. Riogrande) was grown in earthen pots for the growing seasons of 2014 to 2016. Pure culture of the root-knot nematodes were grown in laboratory and were applied at the rate of 50 infective juvenile and 200 eggs per root system through soil drench method. Neem oil and Datura inoxia gave the best results by having lower number (2. 8 and 5. 8, respectively) of galls. Adult females and egg masses were also reduced to 0. 9 and 4. 8, respectively, per root system. All the treatments differences were statistically significant (P≤ 0. 05). Plant growth parameters were also upraised with application of medicinal herbs. This study highlights the nematicidal properties of botanicals for the safe and cheap management of the prevalent root knot nematode. Hence, it is recommended to the farmers for the use of these naturally occurring organic nematicides instead of commercial petro-chemicals that have ill effect on our environment.

In order to investigate the possible presence and molecular features of Peach Latent Mosaic Viroid (PLMVd) in west Iran (Kurdistan Province), a total of 132 leaf samples from almond, apricot, nectarine, peach, plum, sour cherry, and sweet cherry were collected from orchards during the summer of 2016 and 2017. Reverse transcriptionpolymerase chain reaction amplified an expected ~350 base pair DNA fragment from 34 samples. The complete genome sequencing of 17 cloned isolates was determined. Sequence alignment of the new sequences showed 94. 3-100% nucleotide identity, and 79. 2-100% nucleotide identity with other previously reported PLMVd isolates. In phylogenetic analysis, isolated viroid variants from this study and 32 previously reported isolates were placed in two groups (I and II). All the isolated viroid variants in the present study were placed in group II-A (mosaic-inducing isolates), together with other isolates from Australia, China, India, Iran, Spain, Tunisia, and Turkey. The secondary structure of the Iranian variants revealed their unique structures as compared with previously reported isolates of the viroid. To our knowledge, this is the first report of PLMVd infection on apricot, sweet cherry, sour cherry, and nectarine in Iran.

A microtube emitter is a simple, low-cost emitter in which the length can be adjusted according to the distribution of pressures along an irrigation lateral line to deliver uniform discharge. To accurately design micro-irrigation systems using microtubes, it is necessary to use an equation that correlates hydraulic parameters, microtube characteristics, and fluid properties. Therefore, the objectives of this research were: (a) To develop an equation for design purposes using dimensional analysis by Buckingham’ s Pi theorem to represent the hydraulic processes in a microtube emitter operating in the laminar flow regime and (b) To compare the accuracy of the developed model against models that are currently used for microtube sizing. The data required to develop and validate the model was obtained experimentally in the laboratory by evaluating three types of microtubes with nominal diameters of 0. 7, 0. 8 and 1. 0 mm. A model using pressure head, microtube length, flow rate, internal diameter, gravitational acceleration, and water properties was proposed and validated. The model for estimating hydraulic parameters in microtube emitters also presented better performance than other models available in the literature. Finally, an application example was presented and an irrigation lateral line using microtubes as emitters was designed using the proposed model.

The changes in Root Length Density (RLD) of rainfed fig trees due to supplemental irrigation were studied during two growing seasons in Estahban, southern Iran, with objective of finding out the optimum position, time, and amount of supplemental irrigation. Irrigation position treatments were: (1) In a micro-catchment close to tree trunks; (2) Inside the tree canopies (1-1. 1 m from tree trunks); and (3) Outside the tree canopies (2. 1-2. 2 m from tree trunks). Irrigation time treatments included: (a) In early spring and (b) In mid-summer; and the treatments of irrigation amount were: (i) No supplemental irrigation (control), (ii) 1, 000, and (iii) 2, 000 L per tree. Results showed that the highest RLD in different irrigation amounts occurred at 15-45 cm depth during late winter and late spring. However, during summers, the high RLD occurred 15 cm lower at 30-60 cm depth. Irrigation water treatments of 1, 000 and 2, 000 L per tree increased RLD values by 11. 3 and 19. 3%, respectively, in late spring and 10. 5% and 14. 7%, respectively, in late summer, compared with the rainfed treatment. Whereas this increase generally occurred in the wetted area; supplemental irrigation out of tree canopy could develop the root horizontal extension to a greater distance. Lower temporal variation in RLD profile was obtained for depths deeper than 75 cm, which was in agreement with soil water content variations. Supplemental irrigation applied out of tree canopy with 2, 000 L per tree (200 m3 ha-1) during early spring is recommended to improve root development of fig trees in drought prone rainfed areas.