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hrpZ_(Psta)在转基因大豆中定量表达与疫霉根腐病和灰斑病抗性相关研究 总被引:1,自引:0,他引:1
以T5转hrpZPsta基因大豆JN29-705-15和JL30-187为材料,利用实时荧光定量PCR技术(Quantitative Real Time PCR,qRT-PCR)检测了目标基因在转基因大豆不同组织中的表达量,分别利用下胚轴侵染法和叶面喷施法鉴定疫霉根腐病抗性和灰斑病抗性,并分析目的基因表达量与疫霉根腐病和灰斑病抗性的相关性。结果表明:hrpZPsta基因在大豆的叶、茎、根、籽粒中均有表达,二个株系平均相对表达量分别为8.2/6.1、0.9/0.7、6.5/4.6和0.8/0.7;T5转hrpZPsta基因大豆抗疫霉根腐病和灰斑病能力与野生型相比均有所提高,JN29-705-15对疫霉根腐病抗性从感病提高到中抗,而JL30-187从中抗提高到抗病;hrpZPsta基因在叶中的表达量也与抗灰斑病能力呈正相关,与病情级别呈极显著负相关。试验结果初步证明了外源基因hrp ZPsta在大豆植株中的表达量与受体植株对疫霉根腐病和灰斑病抗性存在一定的相关性。 相似文献
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The cowpea aphid (Aphis craccivora) is one of the most important sucking insect pests attacking certain legumes in Egypt particularly faba bean, cowpea and pea. In this study we monitored the resistance level of three field populations of A. craccivora to seven insecticides belonging to three different chemical classes (organophosphates, carbamates and neonicotinoids). The three populations were collected from three governorates in Egypt namely Dakahlia, Qalyobia and Beni Suef. Diagnostic concentrations (LC90 values for susceptible strain) for each insecticide were established using a leaf dipping technique. Resistance monitoring showed that the field population from Dakahlia was highly resistant to all the tested insecticides. In a similar manner, the population from Qalyobia was also resistant to all insecticides except for fenitrothion to which only moderate resistance was observed. The field population from Beni Suef exhibited a lower level of resistance to all the seven tested insecticides.Biochemical assay showed that esterase activity in these three field populations was generally higher as the enzyme activity ratio ranged from 4.3 to 7.8 fold more than that for the susceptible strain. The activity of the other measured detoxifying enzymes (glutathione -S- transferase and mixed function oxidases) was moderate in the populations from Qalyobia and Dakahlia. Nevertheless, the enzyme activity in A. craccivora collected from Beni Suef was variable and differed slightly from the activity measured in the susceptible strain. Monitoring insecticide resistance among the three aphid populations was a proactive approach to detect any shift in insecticide efficiency. The possible occurrence of resistance in the cowpea aphid to the tested insecticides may be due to the higher activity of carboxylesterases. Further studies on the resistance mechanism to these insecticides are needed to provide insights in how to manage and delay the onset of the resistance and thus prolong the performance of insecticides against A. craccivora. 相似文献
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Rats are known to be the most important reservoirs of Leptospira spp. However, the leptospiral dose and age at which rats become resistant to Leptospira infection are not yet well elucidated. Aimed to characterize leptospirosis in rat pups, we found that suckling pups (4-, 7-, and 14-day old) are susceptible to leptospires and resistance starts from the weaning age (23-day old). Susceptibility of rat pups was also affected by the infecting dose of the organisms. Jaundice, decrease in body weight, and neurological symptoms prior to moribundity was evident in infected suckling pups. However, 23-day-old infected pups did not manifest any pathological changes and were able to survive the infection similar to adult rats. Based on these results, we propose the suckling rat pup as a novel animal model of human leptospirosis to investigate pathogenesis, development of host resistance, and the mechanisms involved in rats becoming maintenance hosts for leptospires. 相似文献
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The ascomycete fungus Sclerotinia sclerotiorum is a devastating necrotrophic plant pathogen with an unusually broad host range and worldwide distribution. The benzimidazole fungicide carbendazim has been widely used to control S. sclerotiorum in China for more than three decades and high levels of carbendazim resistance have been reported in eastern China. In this study, carbendazim sensitivity was assessed in a total of 5042 field isolates of S. sclerotiorum collected from different geographical regions of China from 2008 to 2013. Results showed that no carbendazim resistant isolates could be detected in northwestern and northeastern China. In 2013, 0.77% and 0.72% of the field isolates assayed were highly resistant to carbendazim in Hunan and Hubei provinces of central China, respectively. In Anhui province of eastern China, the frequencies of carbendazim resistance were 18.18%, 7.05% and 7.25% in 2008, 2011 and 2012, respectively. The decrease in frequency of carbendazim resistance in Anhui province from 2008 to 2012 was statistically significant (P = 0.001). Nevertheless, no significant differences (P ≥ 0.16) were found in fitness parameters such as mycelial growth on PDA media, virulence to oilseed rape plants and oxalic acid production between carbendazim resistant and sensitive isolates. A negative cross resistance pattern was detected between carbendazim and diethofencarb. Mixture of carbendazim and diethofencarb (4:1) applied at 200 μg/mL provided 100% and 91.5% preventive efficacy against carbendazim resistant and sensitive isolates, respectively, and 87.1% and 81.7% curative efficacy against resistant and sensitive isolates, respectively. 相似文献
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福建省甘薯种质资源鉴定与评价 总被引:2,自引:0,他引:2
征集甄别保存甘薯种质资源606份,编写出品种目录,拍摄了彩色图谱册;摸索出适合福建省气候特点的田间种植、薯块贮藏、老蔓越冬和茎尖脱毒试管苗4种方法相结合的安全保存方法;首次在相同条件下同时完成了对保存的品种资源抗蔓割病、薯瘟病的鉴定,8种主要营养成份的分析及鲜薯与薯干产量的测定,筛选出抗蔓割病资源212份、抗薯瘟病资源109份、高干率资源14份、高淀粉资源12份、高水溶性糖资源13份、高粗蛋白资源13份、高粗脂肪资源12份、低粗纤维资源12份、高维生素C资源12份、高胡萝卜素资源12份,初步摸清了这些品种的分布情况;应用Borlanddel-phi7.0为设计集成环境和通用SQL方式查询程序模块创建了资源数据库;建立了107份骨干资源圃。 相似文献
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通过动力特性分析,解决了拖拉机动力输出轴转速高,输出扭矩较小,不能克服土壤对旋耕机的阻力矩,无法正常作业的问题. 相似文献
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