Climate change impacts modeling on winter wheat yield under full and deficit irrigation in Myandoab-Iran

In this research, impact of climate change on wheat yield was simulated using SWAP in Myandoab, Iran. Field data of wheat in 2004–2005 and 2005–2006 periods were used for calibration and validation of the SWAP, respectively. The HadCM3 outputs, for A1B, A2 and B1 scenarios and 2046–2065 periods, were used in SWAP and wheat yield in mentioned period was compared with base period. Three irrigation levels, based on meeting 100, 70 and 50% of the crop ET demand, were used to study the climate change effects on wheat yield in full and deficit irrigation conditions. The results showed that temperature and reference evapotranspiration will increase in 2055s. Temperature increase cause to decrease crop growing period and crop evapotranspiration. The results showed that the negative impact of temperature increase has dominated to the positive impact of CO₂ concentration and the yield is reduced. For full irrigation situation, the reduction will be 24.1, 22.4 and 20.8% in A1B, A2 and B1, respectively. Reduction in yield can be related to the shorter maturity period of the crop. The results showed that under deficit irrigation, the yield is also decreased but this decrease rate of yield is higher in full irrigation.     

Incidence,distribution and limited genetic variability among Turkish isolates of Grapevine Pinot gris virus from different grapevine cultivars

Journal of Plant Diseases and Protection - Grapevine Pinot gris virus (GPGV) was firstly identified in northern Italy by deep sequencing from grapevine cv. Pinot gris, exhibiting mottling and...     

Interaction of foramsulfuron or nicosulfuron with 2,4-D + MCPA on important broadleaf weeds in corn (Zea mays L.)

Interaction of binary mixture of the two sulfonylurea herbicides: foramsulfuron or nicosulfuron with 2,4-D + MCPA, was evaluated in greenhouse experiments during 2010 and 2011 applying the additive dose model. Plants of redroot pigweed, common lambsquarters, common purslane and black nightshade were sprayed with seven doses of herbicides alone and in binary fixed-ratio mixtures. In total, 35 binary mixtures were studied in 7 separate experiments at ED₉₀ response level. Results indicated that mixture of foramsulfuron + 2,4-D + MCPA was synergistic on redroot pigweed compared to additive interaction between nicosulfuron and 2,4-D + MCPA. Mixture of foramsulfuron + 2,4-D + MCPA was slightly antagonistic on common lambsquarters and an additive interaction was observed with both foramsulfuron and nicosulfuron + 2,4-D + MCPA on common purslane. Finally, the mixture of foramsulfuron or nicosulfuron + 2,4-D + MCPA on black nightshade was antagonistic especially in mixtures where the ratio of sulfonylurea herbicides was more than 2,4-D + MCPA. Totally, 2,4-D + MCPA in mixture with sulfonylurea herbicides especially foramsulfuron provided better control of redroot pigweed in comparison with herbicides applied alone and other herbicide mixtures on weeds.

Abbreviations: 2,4-D + MCPA: ((2,4-Dichlorophenoxy) acetic acid plus (4-chloro-2-methylphenoxy) acetic acid); ADM: additive dose model; a.i.: active ingredient; ALS: acetolactate synthase; DAT: days after treatment; ED: effective dose; Foramsulfuron: (2-(N-((4,6-dimethoxypyrimidin-2-yl)carbamoyl)sulfamoyl)-4-formamido-N,N-dimethylbenzamide); Nicosulfuron: (2-[(4,6-dimethoxypyrimidin-2-yl)carbamoylsulfamoyl]-N,N-dimethylpyridine-3-carboxamide).     

分子标记法和形态学特征对杏仁栽培种及野生种基因型的遗传关系构建的辨别

应用23个形态学特征,19个扩增片段长度多态性(AFLP)引物组合,80个随机扩增多态DNA(RAPD)引物和32个简单序列重复(SSR)引物对,比较三种分子标记法在29个杏仁栽培种和3个野生种遗传关系构建中的信息景和效率.根据预期杂合度的评价,与AFLPs和RAPDs相比,SSRs具有较高水平的多态性和较大的信息量.AFLPs预期朵合度值最低,但其辨别效率值最高,因为AFLPs能揭示每个反应中的大量条带,导致各种类型的多样性指数均较高.三种分子标记法对杏仁基因型的辨别效率均较高,只是SSRs无法辨别‘Monagha'和‘Sefied'杏仁基因型.三种分子标记法基因型相似性相关系数统计上显著,但SSR数据要低于RAPDs和AFLPs的值.尽管三种分子标记法树形图拓扑结构存在一些差异,但相似性水平均较高.SSRs、RAPDs和AFLPs的系统树图及其综合数据都能依据地理散布反映大多数栽培种的关系.AMOVA检测到每个地理组中栽培种和野生种的变异.辅助程序分析表明,实验所应用的标记物数量足以保证基因相似性估计的可靠性和标记法间的比较是有意义的.     

Administration of hot‐water extract of Padina boergesenii via immersion route to enhance haemolymph‐immune responses of Fenneropenaeus indicus (Edwards)

Various polysaccharides extract from marine algae to increase the non‐specific immune system in crustacean. In this study, effects of hot‐water extract on total haemocyte count, total plasma protein, Phagocytic activity, bacterial clearance efficiency and bactericidal activity while the shrimp Fenneropenaeus indicus (10.12±2.18 g) were immersed in seawater (40 g L^?1 and 25±0.8 °C) containing hot‐water extract of brown algae Padina boergesenii at 100, 300 and 500 mg L^?1 for 1–4 h, were investigated. These parameters increased significantly (P<0.05) when the shrimp were immersed in seawater containing hot‐water extract at 100 mg L^?1 after 3 h and 300 and 500 mg L^?1 after 2 h. Fenneropenaeus indicus that were immersed in hot‐water extract at 300 and 500 mg L^?1 had significantly increased phagocytic activity and increased clearance efficiency to Vibrio harveyi after 2 h. But bactericidal activity increased after 1 h immersed in 500 mg L^?1 concentration.     

Screening of sugar beet tissue culture clones for resistance to rhizomania disease

In this study, sugar beet tissue culture clones were used to screen rhizomania resistant genotypes. At first, explants derived from shoot tips of sugar beet seedlings were transferred to shoot tip elongation media after surface sterilization. Then, the grown shoots were transferred to media containing various hormonal combinations NAA, BA, IBA and GA3 for multiplication, growth and rooting. Later, the clones were transferred to soil-peatmoss mixture were adapted to greenhouse conditions. For screening clones against rhizomania, the genotypes of adapted clones were selected and inoculated to rhizomania-infested soil. This experiment was in a randomized complete block design with three replicates (three inoculation times) in greenhouse. Adapted plants were transferred to the soil containing rhizomania virus. All infested soils were diluted 3 to 7 with sand. After two months, infested plants were examined by DAS-ELISA test also optical densities of the samples were analyzed by SAS program. Significant differences among genotypes and blocks were observed. Genotypes were classified to few groups (ranked from completely susceptible to completely resistant). The difference between blocks was because of difference of inoculation time temperature. Use of clones of each genotype caused an increase in selection accuracy of resistant genotypes. By use of this method, chance of escaping from inoculation factor decrease and researchers can determine to be resistance of plants with high level of confidence and apply in breeding programs.     

Short‐term Effects of Genistein on the Reproductive Characteristics of Male Gibel Carp,Carassius auratus gibelio

The objective of this study was to determine the effects of genistein or 17β‐estradiol (E2) on the reproductive physiology in male gibel carp, Carassius auratus gibelio. Maturing male gibel carp received intraperitoneal injections of E2 (10 µg/g body weight), one of two genistein doses (5 µg/g body weight, G5, or 50 µg/g body weight, G50), or the injection vehicle every other day for 10 d. Disruptions in reproductive capacity were determined by measuring indices of sperm quality, plasma metabolites and sex steroids, histological analyses of testes, fertilization rate, and offspring viability. E2 and genistein treatment reduced gonadosomatic index and milt volume, while reduction in spermatozoa concentration and spermatocrit occurred only in E2 and G50‐treated males. Histological examination of the testes indicates that E2 and genistein inhibited reproductive capacity through disruption of the spermatogenesis in males. Genistein reduced fertilization rate and offspring viability at 6 d after hatch (d.a.h.). Plasma testosterone and E2 decreased and increased, respectively, with E2 and G50 treatment. E2 and G50 treatment altered plasma metabolite phosphorus, calcium, cholesterol, and triglyceride. These findings indicate that genistein can negatively affect reproductive capacity in male gibel carp, suggesting that high dietary genistein may impair gonad development.     

Influence of temperature on growth and survival of juvenile winter flounder,Pseudopleuronectes americanus (Walbaum) reared under continuous light

Winter flounder, Pseudopleuronectes americanus, has emerged as a promising candidate flatfish for cold‐water aquaculture and restocking. Here, juveniles were reared for 8 weeks at three temperatures: 10, 15, and 20°C under 24‐hr light. All fish were imaged at stocking and at 2‐week intervals, where growth was measured as changes in standard length (S_L) and body area (B_A). By week 2, fish reared at 15 and 20°C were larger than those grown at 10°C. At weeks 4 to 6, fish at 15°C were larger than fish at 20°C. Linear regressions were used to model growth dynamics over time at each temperature. Highly significant linear growth trajectories were detected over time for S_L and B_A. S_L and B_A regressions also showed a significant difference among the slopes across temperatures, where comparing slopes showed the best temperature to rear the flounder was 15°C. Weights of fish held at 15°C and 20°C were greater than at 10°C at the termination of the experiment. Within each temperature, the growth rate of malpigmented fish was not different from that of the normally pigmented fish. Overall, growth of winter flounder was comparable to that of other commercially produced flatfish species, providing strong evidence for this flatfish species as a potential species for aquaculture.     

Seroprevalence of bovine leukemia virus (BLV) infection in dairy cattle in Isfahan Province, Iran

Bovine leukemia virus (BLV), the causative agent of enzootic bovine leukosis (EBL) is an exogenous C-type oncovirus in the Retroviridae family. It causes significant economic losses associated with the costs of control and eradication programs due to carcass condemnation at slaughter and restrictions of export of cattle and semen to importing countries. The main objective of this research was to determine the seroprevalence of BLV infection in cattle herds in central region of Iran (Isfahan province) using a commercial enzyme-linked immunosorbent assay (ELISA) to detect serum antibodies against BLV. Samples of blood serum were collected from 403 female dairy cattle (Holstein-Friesian) from 21 livestock farms and 303 animals (81.9%) were BLV seropositive. A significant association was found between age as a potential risk factor and BVL seroprevalence with animals ≥ 4 years (86.6%) having a significantly (χ(2) = 35.6, p < 0.001) higher seroprevalence compared to those < 4 years (54.2%). We found no significant statistical association between seroprevalence and pregnancy, lactation status and farming systems as potential risk factors in this study (p > 0.1). It is concluded that BLV infection is a very common problem in the study area. Hence, control measures should be instituted to combat the disease and further studies are required to investigate the impact of this disease on dairy production in the country.     

Three geomorphological rainfall–runoff models based on the linear reservoir concept

Three geomorphological models, based on linear reservoirs cascade, are developed; two of the models are unit hydrograph (UH) models and one contains a non-linear routing approach. In the first UH model, each sub-basin is represented as a cascade of equal linear reservoirs (Nash's model) which directly discharges to the watershed outlet through a linear channel. In the second UH model each sub-basin is represented as a linear reservoir arranged in a sequence based on the drainage network. For both unit hydrograph models, parameters are explicitly derived, which make the models simple and applicable for real world problems. In the third model, output hydrographs of the sub-basins are calculated by the Nash model but with consideration of geomorphological properties of the sub-basins. Then, the obtained hydrographs are routed through the main channel using a non-linear kinematic wave model. Combination of the kinematic wave routing model (a non-linear routing model) and the Nash model (a linear lumped model) makes this third model more appropriate for runoff modeling.Two important properties of these three models are that they consider the effect of watershed geomorphology and include only one parameter which can be estimated using observed rainfall–runoff data. GIS tools are used for determining the watershed geomorphological parameters. The results of these models are compared with the Nash's black box and the geomorphological SCS models for the Amameh watershed, Iran. Although the results show that the proposed models yield good efficiency in rainfall–runoff modeling, the semi-distributed routing ability in the second and third models produces better results.