فهرست مطالب

Journal of Agricultural Science and Technology
Volume:20 Issue: 1, Jan 2018

  • تاریخ انتشار: 1396/11/10
  • تعداد عناوین: 17
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  • A. H. Chizari *, Z. Shokoohi, H. Salami Pages 1-12
    The purpose of this study was to investigate dairy processors market power in Iran. For this purpose, the dynamic imperfect competition model, in which processors are allowed to exert market power in both downstream (selling dairy products) and upstream (buying raw milk from dairy farmers) was applied. Market power parameters, dairy products demand, and raw milk supply elasticities were jointly estimated in a system of equations including market margin, dairy demand, and raw milk supply equations by none linear estimation technique. Data for the period 1992 to 2012 on the industry level were used for estimating an empirical version of the model. The result indicated that conjectural elasticities values were a departure from zero, which reflected non-competitive behavior in dairy market and in raw milk market specifically. Among three dairy products including pasteurized milk, yogurt, and cheese, the conjectural elasticity was the highest for the pasteurized market and the lowest for yogurt . The result suggests that dairy industries processors exercise marketing power in the downstream and upstream market in the dairy products supply chain. Therefore, policymakers must make appropriate policy for facilitating entrance conditions for new dairy processors and improve farmers’ marketing cooperative so as to have more competitive raw milk price.
    Keywords: Conjectural elasticity, Dairy products, Dynamic oligopoly, oligopsony, Dynamic imperfect competition model, market structure
  • M. C. B. De Siqueira, M. A. Ferreira, J. P. I. S. Monnerat, J. L. Silva *, C. T. F. Costa, M. G. ConceiC, Atildeo., A. A. Soares, I. B. De Andrade, J. C. C. Chagas Pages 13-22
    The effect of the inclusion of spineless cactus [0, 14.7, 29.4, 44.1, and 58.8% of Dry Matter (DM)] basis in replacement of Tifton hay on the intake and digestibility of nutrients, feeding behavior, and nitrogen compounds balance were evaluated. Five crossbred steers, rumen fistulated, with average body weight of 380±5.3 kg were assigned to a 5×5 Latin square design. The time spent with rumination activity linearly decreased (P 0.05) to Neutral Detergent Fiber corrected to ash and protein (apNDF), the total digestibility of DM linearly increased (P 0.05), there was a quadratic effect (P
    Keywords: Alternative feed, Drought, Fiber, Intake, Nopalea cochenillifera Salm, Dyck, Rumination time
  • S. Minaei, M. Jafari *, N. Safaie Pages 23-36
    Rose, as one of the oldest flowers in cultivation and the most popular of all cut flowers throughout the world, is susceptible to several diseases. Powdery mildew and gray mold are two of the most common diseases in the greenhouse cultivation of roses. Changes in plant leaf temperature mainly resulting from changes in transpiration in response to such stresses as pathogen infection, water stress, or physiological changes can be monitored instantly and remotely by thermographic imaging. In this research, a smart detection and spraying system was designed and developed to recognize rose powdery mildew and gray mold diseases using a combination of thermal and visible images. The system consists of a thermal camera and a visual camera both mounted on a C-shaped carriage. The carriage is capable of moving along plant rows and rotating around each rose shrub. In addition, a site-specific sprayer was designed that consisted of an electrically-actuated pneumatic directional valve, a pneumatically-actuated directional valve, a pressure regulator, a pressure tank, a compressor, a manual flow control valve, and a nozzle. Droplets volume median diameter, percent of coverage, and system performance in spraying the specified positions were evaluated. Analysis of the pre- and post-spray thermal images showed that such index as temperature median can be successfully exploited to determine spray coverage and uniformity.
    Keywords: Image registration, Percent of coverage, Thermal histogram, Volume median diameter
  • N. Bakhshi, M. Sheikh-Zeinoddin, S. Soleimanian-Zad * Pages 37-49
    Given the growing interest in the production of new and low cost bioemulsifiers, the rice and wheat bran and straw were investigated in this study for the production of bioemulsifier by Lactobacillus plantarum subsp. plantarum PTCC 1896 (probiotic). The strain produced bioemulsifier only in the rice bran hydrolysate medium. The bioemulsifier amount reached around 0.7 g L-1 for 72 hours of fermentation. The new biomolecule was extracted, purified, and its structural and thermal properties were evaluated. The functional groups and the structure of the molecule were revealed by GPC, FT-IR, 1HNMR and 13CNMR techniques. The bioemulsifier was a water soluble extracellular high molecular weight (>107 Da) α-glucan (81.74%) bound with protein (18.18%). Thermal behavior was studied using DSC and TG analysis. Thermal analysis showed the bioemulsifier broke down above 211.74°C, and the melting point was 182.0°C with the enthalpy value of 101.7 J g-1. These results might provide incentives for the industrial production of the biodegradable and safe bioemulsifier introduced in this study, which seems to offer potential applications in the food and medical industries.
    Keywords: Probiotic, Rice bran hydrolysate, Structural properties, Thermal analysis
  • M. Faramarzi *, Z. Heidarizadi, A. Mohamadi, M. Heydari Pages 51-60
    This study aimed first to investigate the relationship between Normalized Difference Vegetation Index (NDVI) and vegetation attributes (vegetation cover, bare soil, litter frequency, and the amount of biomass) and, then, evaluating the vegetation changes using NDVI in semi-arid rangeland in western Iran. Ground data were collected to assess the accuracy of NDVI index. For this purpose, 14 sampling units were randomly selected for collection of vegetation attributes including biomass, vegetation cover, litter, and bare soil. Then, the correlation between digital pixel values and the sampling units were analyzed. The results showed that NDVI was highly correlated with all vegetation attributes. The maximum correlation was related to vegetation cover (0.84). So, to evaluate the vegetation changes, the NDVI maps were created in 1986, 2001, and 2013. The results showed that the amount of class 1 (very poor vegetation cover) increased from 0.27 km2 in 1986 to 12.89 km2 in 2013, and also class 4 and 5 (good and very good vegetation cover, respectively) decreased about 27.8 and 37.7%, respectively. The relationship between precipitation and temperature with NDVI was investigated to assess the sensitivity of NDVI to these parameters. The results showed that the amount of precipitation decreased during the studied time periods. This parameter seems to be one of the most important factors affecting the vegetation in our study area.
    Keywords: Precipitation, Satellite imagery, Temperature, Vegetation cover
  • M. K. Gullap, S. Erkovan, H. I. Erkovan *, A. Koc Pages 61-70
    The effect of fire on vegetation of semi-arid steppe has not been studied extensively. Wildfires are rare in some steppe rangelands because of high levels of large herbivore grazing. However, grazing is sometimes restricted or excluded in areas such as national parks or the areas where afforestation projects are conducted. Therefore, sometimes, wildfires occur during the dormant season when litter (the uppermost layer of organic debris on the soil surface; essentially the freshly fallen or slightly decomposed vegetal material) mass has resulted in peak levels. Our study assessed the effects of a single fire on litter mass, forage production, and forage crude protein, Neutral Detergent Fiber (NDF), and Acid Detergent Fiber (ADF) in high altitude rangelands of Eastern Anatolia. We found significant effects of treatment (fire and no fire), years, and sampling date on all variables. Following the prescribed fire in 2011, litter mass and forage production was less in treated plots compared to untreated control plots during both years. The effect of the fire on litter and forage production was more pronounced in 2012 compared to 2013. The effects of the fire on forage quality variables were also greater in 2012 than in 2013. Forage crude protein levels were consistently higher in treated plots during all 2012 sampling periods. Similarly, NDF and ADF tended to be lower in treated plots relative to the control plots during 2012. All effects we found were more pronounced in the first growing season following the fire compared to the second growing season, suggesting a relatively transient nature of fire effects in the steppe vegetation we studied.
    Keywords: ADF, Litter mass, NDF, Organic debris, Semi, arid rangelands
  • T. O. Genc*, F. Yilmaz Pages 71-82
    The concentration of heavy metals (Hg, Cd, As, Cu, Pb, Cr, and Zn) in the water, sediment and fish (Mugil cephalus) were investigated from different sites on Köyceğiz Lagoon System. Potential ecological risk analysis of heavy metal concentrations in sediments underlined considerable ecological risk for two sites of the lagoon during winter and spring. The ratio of transfer factors of Hg, Cr, Cu, Zn, and As in fish from water was higher than 1, which means that fish undergo bioaccumulation of these elements from lagoon water. The determination of individual Target Hazard Quotients (THQs) in fish tissue indicated safe levels for the local people, but there is a possible risk in terms of total THQ because the highest THQ value of As suggests that they may experience a certain degree of adverse health effect.
    Keywords: Bioaccumulation, Ecological risk, Health risk, Köyceğiz, Target hazard quotients
  • Y. Fathipour *, E. Chegeni, S. Moharramipour Pages 83-94
    In this study, the nutritional indices of the larval stages of Helicoverpa armigera (Hübner) were determined on 10 canola (Brassica napus L.) genotypes (Talaye, Opera, Licord, Modena, SLM046, Hayula420, Zarfam, Okapi, RGS003 and Sarigol) at 25±1˚C, 60±5% RH and a photoperiod of 16: 8 (L: D) hours. The third instar larvae reared on Talaye showed the highest value of Efficiency of Conversion of Ingested food ECI and Efficiency of Conversion of Digested food ECD (7.005±0.632 and 8.972±1.862, respectively). However, the lowest value of ECI and ECD was on Licord (0.503±0.017 and 2.507±0.449, respectively). The highest (0.778±0.091) and lowest (0.594±0.059) Relative Growth Rate (RGR) of the fourth instar larvae were obtained on SLM046 and Sarigol, respectively. Results indicated that the highest values of ECI and ECD for fourth instar larvae were on Talaye (6.300±0.585 and 8.880±1.954, respectively). The lowest value of the Relative Consumption Rate (RCR) and Approximate Digestibility (AD) of the fifth instar was recorded on Modena (5.193±0.629 and 38.625±11.340, respectively). The ECI and ECD values of the fifth larval instar were the highest on Talaye (9.893±0.889 and 19.655±0.966, respectively). The highest value of RCR and AD of the sixth instar was on Okapi (7.781±0.665 and 82.223±1.922, respectively). Among different genotypes tested, the highest ECI and ECD of the whole larval instars (12.323±0.310 and 32.357±5.508, respectively) were observed on Talaye and the lowest ones (5.947±0.257 and 6.922±0.320, respectively) were on Okapi. Together, Talaye and Okapi were the most suitable and unsuitable genotypes, respectively, for H. armigera larvae.
    Keywords: Approximate digestibility, Brassica napus, Digested food, Ingested food, Relative growth rate
  • K. Wang, G. M. Liu, C. M. Song, S. Su, M. H. Chen* Pages 95-107
    Mitochondrial DNA (mtDNA) is an important genetic marker in population and evolutionary biology. To test the feasibility of two mitochondrial gene markers (COI and Cytb) for Rhopalosiphum padi, we collected 275 individuals of the insect species from 15 locations, which cover most of the species’ distribution range in China, and analyzed the diversity of the two genes. Seven COI haplotypes and 15 Cytb haplotypes were identified by 13 and 36 polymorphic sites, respectively. Across the entire samples, the average haplotype diversities (Hd) of COI and Cytb were 0.491 and 0.607, and the nucleotide diversities (π) of COI and Cytb were 0.147% and 0.160%, respectively. Relatively low levels of genetic diversity and genetic differentiation were observed among all R. padi populations based on the two genes. Moreover, parsimony networks of the COI and Cytb haplotypes of R. padi all supported a single clade. Although the nucleotide variation of mitochondrial genes has been used in other insect species, reviewing the recent literatures on mitochondrial diversity in aphid species, we found that the population and evolutionary biology of aphids including R. padi, could not be elucidated by analyzing mtDNA alone, mostly because of the low genetic variation of mitochondrial genetic markers among populations. We suggest the combined use of mtDNA and other genetic markers, such as microsatellites, to overcome the low genetic information provided by mtDNA in evolutionary studies on aphid populations.
    Keywords: COI, Cytb, Gene markers, mtDNA, Population biology
  • J. Koodziejek * Pages 109-120
    In some European countries, Adonis flammea is very rare and endangered primarily due to increasing fertilizer and herbicide use, more efficient seed cleaning, and strong soil acidification. The aims of this study were to determine the requirements for embryo growth, dormancy break, and seed germination to characterize the type of seed dormancy (via effects of GA3) and to evaluate the effects of light on germination ability. Germination responses of A. flammea were tested in light and dark conditions at three alternating temperatures (15/5°C, 20/10°C, 25/15°C) after stratification. Embryo growth was determined by measuring its lengths. Fresh seeds did not germinate during one month of incubation in either light or darkness over a range of temperatures. Seeds of A. flammea had underdeveloped embryos that must grow from about 0.2 to 1.5 mm in length before radicle emergence (germination); thus they had Morphological Dormancy (MD). In addition to MD, the seeds also had Physiological Dormancy (PD) at maturity in mid-July; moreover, the embryos grew during warm stratification, and the seeds needed a subsequent period of cold stratification to germinate. Thus, MD had been broken, but PD prevented germination. Therefore, the seeds have morpho-physiological dormancy. Germination was promoted by 12 weeks of warm stratification followed by 12 weeks of cold stratification. In conclusion, good conservation management in arable land for A. flammea involves annual cultivation, ideally in mid-summer (warm stratification) without subsequent disturbance until the following summer.
    Keywords: Embryo length, Gibberellic acid, Morpho, physiological seed dormancy
  • J. Dyko *, S. Kaniszewski Pages 121-128
    Fertilization of plants in greenhouse soilless cultivation is used in a closed system with recirculating nutrient solution or in an open system where the excess of nutrient solution is discharged into the soil or sewage. In Poland, most of basic greenhouse vegetables are grown in the open soilless system. The excess of highly concentrated nutrient solution leaking from growing slabs causes contamination of soil and shallow groundwater. The aim of the study was to monitor component changes in nutrient solution and nitrate nitrogen in the plant root zone, drainage water, as well as in shallow groundwater present in arable lands in the immediate vicinity of the soilless tomato culture. The study was conducted in 2013 - 2015 and compared tomato cultivated in Rockwool versus biodegradable organic substrate. Changes of nutrient content including N-NO3 in the root zone and drainage water depended on the type of the substrate in which tomato plant was cultivated as well as on the plant growth stage. Higher content of nitrate nitrogen in the root zone and drainage water was found in tomatoes grown in Rockwool compared to the organic substrate. The peak content of N–NO3 (117 mg dm-3) was detected in the groundwater present directly under the soilless tomato culture and it decreased proportionally to the distance from the greenhouse.
    Keywords: Drainage water, Nitrate nitrogen, Nutrient solution, Organic substrate
  • M. J. Ahmadi Lahijani, M. Kafi *, A. Nezami, J. Nabati, J. Erwin Pages 129-139
    Possibility of improving physiological traits and minituber yield of potato cultivars (cvs. Agria and Fontane) was investigated by application of plant growth regulators (BAP, ABA and BAP) at tuber initiation stage. Regardless of the cultivars, Net photosynthesis rate (Np), actual quantum yield (Φ), stomatal conductance (gs) and Transpiration rate (Tr) of BAP-treated leaves were superior to those of the control. For Agria, the greatest Chlorophyll content (Chl) was observed in BAP-treated plants, while the highest Chl for Fontane was observed in ABA-treated plants. Increasing Np and Chl content were associated with higher Soluble Carbohydrate content (SC). BAP application increased SC of leaflets in both cultivars compared with the control. Tuber Yield per Plant (Y/P), Mean Tuber Weight (MTW), and Tuber Number (TN) were stimulated by foliar treatment of plants with PGRs compared with the untreated ones, but there were significant interactions between cultivar and hormone type. Positive correlation between SC and Y/P (r= 0.97*) and MTW (r= 0.97*) were observed in Agria. Leaf area as well as dry and fresh weight of aerial parts of the BAPtreated plants were more than the untreated plants and other PGR treatments. These results indicate that either of BAP, ABA, or their combination could be effectively used to improve physiological traits and tuber yield of these cultivars, although, Agria responded more prominently to PGRs than Fontane.
    Keywords: Net photosynthesis rate, Photosynthetic pigments, Plant growth regulators, Soluble carbohydrate, Tuberization
  • P. Neha*, S. S. Solankey, K. Barman, S. Akhtar, M. Kumari Pages 141-152
    In this study, fifteen commercial varieties, nine exotic genotypes, and three wild species of tomato grown in Eastern India were analyzed for variations in different phytochemicals viz. ascorbic acid, lycopene, total carotenoids, total phenolics content and total antioxidant capacity. Selected genotypes showed significant differences with respect to phytochemical composition. Among antioxidant property parameter, ascorbic acid content ranged between 12.62 to 76.15 mg 100 g-1 of Fresh Weight (FW), whereas, the total phenolic content and total antioxidant capacity varied from 41.10 to 139.59 mg GAE 100 g-1 of FW and 1.16 to 4.52 µmol Trolex Equivalent (TE) g-1 of FW, respectively. Among carotenoid parameters, lycopene and total carotenoids content in whole tomato fruit ranged between 0.47 to 5.48 and 1.14 to 5.79 mg 100 g-1 of FW, respectively. Interestingly, it was found that, among the evaluated genotypes, Exotic Collection (EC lines) showed significant enriched amount of these phytochemicals. Results indicated that the maximum ascorbic acid (76.15 mg 100 g-1 FW), total phenolics content (139.59 mg GAE 100 g-1 of FW), and total antioxidant capacity (4.52 µmol TE g-1 of FW) was highest in exotic collection EC 528372, while, lycopene (5.48 mg 100 g-1 of FW) and total carotenoids content (5.79 mg 100 g-1 of FW) were recorded highest in cultivar Rio Grande. Thus, this group of screened genotypes consisting of phytochemical rich wild species and exotic collection can be further used for improvement of functional quality of tomato in future breeding programs of India and the Indo Gangetic region.
    Keywords: Antioxidant, Ascorbic acid, Carotenoid parameters, Lycopene
  • S. Tekdal, E. Kendal * Pages 153-166
    The goal of this research was to assess the stability and yield performance of 150 durum wheat genotypes in multi-environment trials in two locations (Diyarbakir and Kiziltepe), in 2011-2012, and 2012-2013 growing seasons. The trials were designed by Lattice Experimental Design with two replications (incomplete block design). The AMMI (Additive Main Effects and Multiplicative Interaction) and GEI (Genotype×Environment Interaction) analysis were used in the study to estimate GEI effects on grain yield, because of plant breeders’ great interest in these models for breeding programs. AMMI evaluation indicated that genotypes made the most important contributions to treatments Sum of Squares (59.8%), environments (3.5%), and GEI (36.7%), respectively, suggesting that grain yield had been affected by environment. IPCA 1 and IPCA 2 axes (Principal Component) were significant as P
    Keywords: AMMI, GGE biplot, Rain fed wheat, Stability
  • M. J. Hong, Y. H. Yoon, D. S. Kim, S. H. Kim, S. Y. Kang, D. Y. Kim, Y. W. Seo, J. B. Kim* Pages 167-178
    The objectives of this study were to determine the effects of chronic gamma irradiation on growth and biochemical characteristics of wheat. Wheat plants were exposed to a 60Co gamma rays at doses ranging from 10 to 150 Gy for 3 weeks. Our results indicate that irradiation at 10–15 Gy enhanced plant growth as compared to non-irradiated wheat, while at high doses (>20 Gy) a significant decrease in wheat height was recorded. APX and CAT transcript levels were higher in plant irradiated at 12.5 Gy than in the controls. Also, the enzyme activities of APX and CAT and POD were increased by 12.5 Gy gamma irradiation. Chronic irradiation caused an increase in the total anthocyanin content. To assess whether anthocyanin biosynthesis-related genes were involved in the response to chronic gamma irradiation in wheat plants, we examined their expression under different doses of gamma rays. Levels of F3H, DFR, ANS transcripts increased due to chronic gamma irradiation, whereas CHS and CHI expression decreased. Total anthocyanin contents significantly increased after chronic irradiation. Furthermore, Ultra Performance Liquid Chromatography (UPLC) revealed that cyanidin 3-glucoside, one of the anthocyanin compounds, rapidly increased in wheat plants after chronic gamma irradiation. This study demonstrated that the growth of wheat plants and markers of biochemical activity were negatively influenced by chronic gamma irradiation in a dosedependent manner, although low-dose radiation showed stimulatory effects. Results from this study are very useful for future chronic gamma irradiation studies for the improvement of wheat varieties.
    Keywords: Anthocyanin, Antioxidant, Biochemical activity, Reactive oxygen species, Cyanidin 3, glucoside
  • A. Zeynadini-Riseh, E. Mahdikhani-Moghadam*, H. Rouhani, M. Moradi, R. Sabeririseh, A. Mohammadi Pages 179-191
    Root-knot nematodes are the most economically important plant pathogens in pistachio. The ability of Pseudomonas fluorescens strains VUPF5, VUPF52, Bacillus cereus strain PRC95 and Bacillus subtilis strain PRC96 were tested as biocontrol agents for Meloidogyne incognita on the pistachio cultivars Sarakhs and Badami. The effect of these bacterial strains on defenserelated enzymes activity in pistachio was also investigated. Pistachio seedlings of both cultivars were treated with bacterial strains and then were inoculated with 2000 second-stage juveniles of nematode after two days. Evaluations were made for changes of Peroxidase (POX), PolyPhenolOxidase (PPO), Phenylalanine Ammonia lyase (PAL) and Total Phenolic Content (TPC) determined at 2, 4, 7, and 10 Days After nematode Inoculation (DAI). Results showed improved activity of POX, PAL and PPO in both cultivars. The most significant result for POX activity in the treated seedlings belonged to Pseudomonas strain VUPF5 at 7 DAI for Sarakhs and 10 DAI for Badami. However, this strain displayed an increase in PAL activity at 2 and 4 DAI in Badami and Sarakhs, respectively. Seedlings treated by the Pseudomonas strain VUPF52 at 10 DAI had the highest PPO activity among cultivars. TPC concentration was slightly higher, by 8.4% at 4 DAI, in Sarakhs seedlings treated with VUPF5, but no significant increase could be seen in the Badami cultivar compared with the control. In another experiment, 4 months after nematode inoculation in seedlings of both cultivars treated by bacterial strains, numbers of galls, egg masses, and second juveniles decreased compared with the non-treated seedlings.
    Keywords: Bacillus subtilis, Pistachia vera cvs. Badami, Sarakhs, Root knot nematode
  • S. Pirayesh *, H. Zamanizadeh, B. Morid Pages 193-202
    Recently, vascular wilt disease has caused considerable damages in tomato greenhouses. Fusarium oxysporum is a common pathogen of tomato and produces a variety of toxins, pigments, and phytohormones. It has caused huge crop damage in south of Iran. Damage increases in relatively warm climate. Fusarium oxysporum were identified from contaminated tissues. Thirty five of 50 isolates from samples collected from tomato greenhouses in southeast of Iran were identified as F. oxysporom. Then, F. oxysporum f. sp. lycopersici (Fol) and F. oxysporum f. sp. radicis lycopersici (Forl) were differentiated from each other by host range and molecular methods. Fol is only pathogenic on tomato and Forl is pathogenic on other hosts from Cucurbitaceae family in addition to tomato. Molecular identification of isolates was obtained by Hirano methods. DNAs of each isolates were reproduced by using uni, sp13 and sp23 specific primers. Based on this study, 4 isolates were identified as race1, 4 isolates as race 2, 13 isolates as race 3, and 14 isolates as Forl. This is the first report of formae specialis and physiological races of this pathogen in this region. Race 3 is reported for the first time in Iran.
    Keywords: Formae speciales, PCR, Physiological races, Specific primer