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51.
Javad Rezaei Mohammad Bannayan Ahmad Nezami Mohsen Mehrvar Bagher Mahmoodi 《Journal of Crop Science and Biotechnology》2014,17(2):59-69
Viral disease of rhizomania is one of the most important diseases of sugar beet all over the world. The disease significantly has reduced the yield and quality of sugar beet, and has imposed high economic loss to farmers. Long-term breeding programs to introduce tolerant cultivars are the only chance of avoiding further yield losses. This study tried to measure and analyze the growth of shoots and roots of rhizomania-tolerant and -susceptible sugar beet with the aim of providing information for modeling of the rhizomania effects on the growth of sugar beet. Growth indices were used for analyzing, quantification, and time-course of sugar beet growth under infested and non-infested soils conditions. A 2-year experiment was conducted using four sugar beet cultivars in 2010 and 2011 in Mashhad, Iran. The results of this study showed that under infested soils, root dry matter and leaf area index of the susceptible cultivars in comparison to tolerant cultivars were lower by 57 and 24%, respectively. In addition, crop growth rate and net assimilation rate of susceptible cultivars were affected by rhizomania and were lower than in tolerant cultivars. On non-infested soil, the difference between dry matter and growth indices of susceptible and tolerant sugar beet cultivars was not significant. Rhizomania decreased green area and photosynthesis capacity and led to lower growth rate and dry matter production. Our study quantified the growth of rhizomania-infested sugar beet plants in comparison with non-infested plants and provided information to be used for modeling of the rhizomania effects on the growth of sugar beet. 相似文献
52.
Hamzeh Amiri Ahmad Ismaili Saeed Reza Hosseinzadeh 《Compost science & utilization》2017,25(3):152-165
One goal in the face of deficit water conditions is to increase growth and yield. Agro-industrial production frequently causes environmental pollution by using chemical fertilizers. In recent decades, bio-fertilizers such as vermicompost have been used as a safe alternative to chemical fertilizer. The present study considered the response of the chickpea to different combinations of vermicompost and water deficit stress in a greenhouse environment. Plant response was determined by measuring a range of morpho-physiologic parameters. The treatments were addition of 0%, 10%, 20%, and 30% of vermicompost to soil, and water deficit stress at the following levels: non-stress (100% of field capacity), moderate water stress (75% of field capacity), and severe water stress (25% of field capacity). The results showed that vermicompost had a significant effect on all traits under stress and non-stress conditions. The vermicompost treatments under non-stress conditions significantly increased plant height, number of pods, leaf area, stem and leaf dry weight, pod dry weight, chlorophyll a, carotenoid, total chlorophyll content, CO2 assimilation rate, internal CO2 concentration, and water-use efficiency over that of the control condition. The addition of 30% vermicompost under moderate and severe water stress conditions significantly increased plant height, number of pods, leaf area, leaf dry weight, carotenoids, and water-use efficiency over that of the control level. This study confirmed that vermicompost improved the morphological features, soil biological activity, and quality of the chickpea, but did not positively influence the physiological features under moderate and severe water deficit stress. 相似文献
53.
Mehraneh Sepasi Behnam Amiri Besheli 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2019,69(2):114-120
Purpose: Citrus white snail, Helicella candeharica Pfeiffer (Panpulmonata: Helicidae) is one of the most important orchard pests. In this study, the effectiveness of mineral oil was compared with molluscicide baits such as metaldehyde, ferricole (iron phosphate) and a snail-repellent paint in a commercial citrus orchard in northern Iran to reduce access of citrus white snails to citrus trees.
Materials and methods: The number of snails on citrus trees was monitored and counted 10 days after the application of the treatments, and at an interval of 6–8 days up to harvest time.
Results: In the first study, the mineral oil and repellent paint treatments reduced a number of snails best. In the second study, using metaldehyde and mineral oil barrier, again the mineral oil barrier reduced snails best. The cost of each treatment during one season per hectare was calculated at 55, 153, 124 and 120?$/ha for mineral oil, iron phosphate, snail-repellent paint and metaldehyde, respectively.
Conclusions: Mineral oil is an effective alternative for chemical compounds for reducing access by H. candeharica to citrus trees. 相似文献
54.
Shirin Pournourmohammadi Seyed Nasser Ostad Mohammad Hossein Ghahremani Bagher Minaie Mohammad Abdollahi 《Pesticide biochemistry and physiology》2007,88(3):346-352
Hyperglycemia is observed with exposure to organophosphorus (OP) pesticides. The aim of this study was to investigate the effects of malathion on secretion of insulin from rat pancreatic islets in vitro and in vivo. Malathion was administered through food for 4 weeks at concentrations of 100, 200, and 400 ppm. For in vivo experiment, at the end of treatment, blood sample was obtained and plasma was separated. For in vitro experiment, the treated rats were anesthetized and underwent a laparatomy. The common bile duct was cannulated and the pancreas distended by injecting of cold collagenase V using peristaltic infusion pump. Islets were then hand picked under a stereomicroscope and cultured in the presence of various doses of glucose and KCl. Malathion at doses of 200 and 400 ppm increased plasma glucose and insulin concentrations and lowered activity of erythrocyte acetylcholinesterase. The isolated islets from pretreated animals with malathion 200 and 400 ppm showed lower glucose-stimulated insulin secretion while no change was observed in the presence of KCl. Light microscopic examination revealed that malathion causes patchy degenerative changes in pancreatic islets. Combination of in vivo and in vitro findings suggests that malathion induces a kind of insulin resistance that cannot overwhelm hyperglycemia. This action of malathion is mediated through disruption of islets mitochondrial function. 相似文献
55.
Measurement of Ovine Pregnancy-Associated Glycoprotein (PAG) During Early Pregnancy in Lacaune Sheep
B El Amiri A Karen J Sulon N Melo de Sousa AV Alvarez-Oxiley Y Cognié O Szenci JF Beckers 《Reproduction in domestic animals》2007,42(3):257-262
This study describes ovine pregnancy‐associated glycoprotein (ovPAG) concentrations in 20 Lacaune sheep during early pregnancy. Measurements were performed by using semi‐purified ovPAG as standard, tracer and immunogens for antibody production in rabbits. Antisera R780 (against ovPAG57+59kDa) and R805 (against ovPAG558+61kDa) were used respectively in RIA‐780 and RIA‐805. Blood samples were collected at days 0, 18, 20, 22 and 25 after artificial insemination. From day 18 after breeding onward, the mean ovPAG concentration was significantly higher (p < 0.001) in plasma samples from pregnant ewes (n = 17) than in non‐pregnant ones (n = 3). The specific activity of the tracer was 11 760 Ci/mmol in RIA‐780 and 14 900 Ci/mmol in RIA‐805. The minimal detection limits for RIA‐780 and RIA‐805 were 0.2 ng/ml and 0.3 ng/ml, respectively. The intra‐assay CV of samples with low (1.0 ng/ml), medium (2.5 ng/ml) and high (4.0 ng/ml) PAG concentrations were 3%, 6% and 9% for RIA‐780 and 8%, 9% and 5% for RIA‐805. The inter‐assay CV in the same samples were 13%, 12% and 7% for RIA‐780 and 13%, 11% and 5% for RIA‐805. The recovery was higher than 95% in both assays. No cross‐reaction was observed with members of aspartic proteinase family as well as with other tested proteins. In both RIA‐780 and RIA‐805, inhibition of the binding of the tracer by antisera was parallel between standard curve and serial dilutions of pregnant ewe samples. In conclusion, the two homologous RIA systems are suitable for early quantification of ovPAG concentrations in ewe plasma samples from day 18 after breeding. 相似文献
56.
Saeed Hajirezaee Bagher Mojazi Amiri Mehdi Mehrpoosh Samane Nazeri Hamid Niksirat 《Aquaculture Research》2011,42(12):1789-1795
To determine the effect of gonadotropin releasing hormone‐analogue (GnRHa) treatment on the milt quality of endangered Caspian brown trout, Salmo trutta caspius, the sperm motility (percentage and duration of motility), sperm production (sperm density, spermatocrit and milt volume) and milt pH were measured for GnRHa‐treated (the treatment group) and untreated groups (the control group) during the spawning season. For untreated brooders, the values of the motility per cent, sperm density and spermatocrit decreased continuously during the spawning season while the milt volume, duration of motility and milt pH showed only a significant decrease at the end of the season. For GnRHa‐treated males, these parameters increased 14 days after GnRHa treatment (first milt collection) and then decreased continuously towards the end of the season. In addition, the values of milt and sperm density yielded per treated male were higher than that in the untreated group, although these were not statistically different. In any case, the total sum of yielded milt from the treatment group over the spawning season was higher than that in the untreated group. In this experiment, significant positive correlations were found between milt parameters as follows: sperm motility vs. milt pH; sperm density vs. spermatocrit; milt volume vs. spermatocrit; and milt volume vs. sperm density. The results show that the treatment of Caspian brown trout by GnRHa can improve the milt quality in terms of sperm motility and sperm production during a spawning season. 相似文献
57.
Amiri F 《Pakistan journal of biological sciences: PJBS》2008,11(8):1132-1136
The objective of this study closely focuses on the settlement of the effect of marginal land use on plant diversity. The location of this study was Sar Firouze Abad region with rainfall of over 350 mm and slope of over 12%. Five treatments in terms of land use (exclusion area, grazed range, fallow, annual medic cultivation, wheat cultivation) done with the repetition of five times. The factors, such as the number of species, the number of plant bases in each species, the percentage of plant cover and biomass in each sampling were measured. The method used here is based upon complete randomized design applying Duncan test and Raunkiaer method for classification of plant species and also Shannon's diversity index of diversity and homogeny utilized. The results show that there are 76 species belonging to 60 genus and 19 families spreading in the region under study. The most dominant families are Fabaceae with 15 species covering 20% and Poaceae with 13 species covering 17%, respectively. According to Raunkiaer method the life form of the region species can be classified as Therophytes 66%, Geophytes 3%, Hemicryptophytes 26% and Chamaephytes 5%. The results also illustrate that the treatment of exclusion area has the most plant diversity, the percentage of plant cover and biomass in comparison with the rest of treatment cultivation and range grazed. 相似文献
58.
The Effects of Brackish Water on Growth Hormone/Insulin‐like Growth Factor‐1 Gene Expression of the Caspian Trout,Salmo trutta caspius (Kessler, 1877), During the Early Stage of Smoltification 
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Mohammad E. Amiri Esmaeil Fallahi Masumeh Safi-Songhorabad 《Journal of plant nutrition》2014,37(1):16-29
Influence of four rootstocks (M.9, MM.106, MM.111, and local seedling) on the scion leaf and fruit mineral concentrations, tree growth, yield and fruit quality attributes of ‘Golden Delicious’ and ‘Royal Gala’ apples during four seasons (2008–2011) were significant. The mechanisms behind the influence of rootstock on scion vigor and yield was that the rootstock brought about its effects upon the scion by influencing the amounts of minerals taken up and translocated to the scion. ‘Royal Gala’ and ‘Golden Delicious’ trees on seedling had the highest efficiency in calcium (Ca) and potassium (K) uptake. Whereas, trees of these cultivars on M.9 were more efficient in nitrogen (N), manganese (Mn) and iron (Fe) uptake. MM.106 had the highest efficiency in phosphorous (P) uptake, and M.9 had the lowest K and Ca uptake. The highest N- fruit concentration and the lowest Ca-fruit concentration were observed in cultivars on M.9. 相似文献
60.
This study evaluated CERES-Rice, AquaCrop, and ORYZA2000 models performance in simulation of biological and grain yield of rice in response to different irrigation intervals and nitrogen levels. These models were calibrated and validated by using three years (2005 to 2007) field experiments. Three levels of irrigation interval included pond treatment, five days interval, and eight days interval, and consisted of four levels of nitrogen. The study results showed that there were significant differences among study crop models in simulation of grain and biological yield in response to different irrigation intervals. As results showed, study models performed more accurate in estimation of rice yield under irrigation intervals than nitrogen levels. All models illustrated high performance in estimation of rice yield under different irrigation intervals. CERES-Rice and AquaCrop models showed highest accuracy in simulation of grain and biological yield of rice under different levels of nitrogen, respectively. In addition, CERES-Rice model indicated highest performance in simulation of grain yield (rRMSE = 16). However, AquaCrop model estimated biological yield more accurate compared to other models (rRMSE = 15). ORYZA2000 showed less accurate in simulating grain (rRMSE = 23) and biological (rRMSE = 21) yield of rice in comparison with other models. 相似文献