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971.
近年来,饲用苎麻产业快速发展,收获难的问题成为制约其发展的瓶颈。在分析当前饲用苎麻机械化收获发展现状的基础上,指出了当前存在的主要问题,并提出了相应的对策措施。  相似文献   
972.
To provide genetic information and materials for breeding hybrid japonica rice with wide adaptability and strong competitive advantage of yield,elite alleles and their carrier varieties of growth duration (GD) and productive panicle number per plant (PN) were detected.A natural population composed of 94 japonica varieties was phenotyped for the GD,PN and plant height (PH) in two environments.The conditional phenotypic data were transferred by the linear model method in software QGAStation 1.0,and association mapping based on the unconditional and conditional phenotype values of GD and PN was analyzed by using general linear model in software TASSEL.A total of 34 simple sequence repeat (SSR) marker loci associated with GD and PN were detected in the two environments.Among them,15 were associated with GD,and 19 were associated with PN.Four elite alleles of RM8095-120bp,RM7102-176bp,RM72-170bp and RM72-178bp were associated with GD,and their carrier varieties were Hongmangshajing,Nipponbare,Hongmangshajing and Nannongjing 62401,respectively.These elite alleles from the carrier varieties can shorten GD by 2.03 9.93 d when they were introduced into improved materials.RM72-182bp associated with PN was an elite allele,and its carrier variety was Xiaoqingzhong.It can increase PN by three when introduced into improved materials.Moreover,these elite alleles can be used to improve target traits without influencing another two traits.  相似文献   
973.
Setosphaeria turcica, an essential phytopathogenic fungus, is the primary cause of serious yield losses in corn; however, its pathogenic mechanism is poorly understood. We cloned STK2, a newly discovered mitogen-activated protein kinase gene with a deduced amino acid sequence that is 96% identical to MAK2 from Phaeosphaeria nodorum, 56% identical to KSS1 and 57% identical to FUS3 from Saccharomyces cerevisiae. To deduce Stk2 function in S. turcica and to identify the genetic relationship between STK2 and KSS1/FUS3 from S. cerevisiae, a restructured vector containing the open reading frame of STK2 was transformed into a fus3/kss1 double deletion mutant of S. cerevisiae. The results show that the STK2 complementary strain clearly formed pseudohyphae and ascospores, and the strain grew on the surface of the medium after rinsing with sterile water and the characteristics of the complementary strain was the same as the wild-type strain. Moreover, STK2 complemented the function of KSS1 in filamentation and invasive growth, as well as the mating behavior of FUS3 in S. cerevisiae, however, its exact functions in S. turcica will be studied in the future research.  相似文献   
974.
为了获得纯化的SnRK1.1与FD蛋白,分析蛋白激酶SnRK1.1是否能够磷酸化开花调控途径中的转录因子FD,成功克隆了1 608 bp的SnRK1.1基因以及858 bp的FD与FD-T282A基因,分别与PGEX-4T-3载体连接,获得原核表达载体GST-SnRK1.1、GST-FD和GST-FD-T282A,并分别转化大肠杆菌BL21菌株;SDS-PAGE电泳和考马斯亮蓝染色(CBB)表明,0.5 mmol/L IPTG能够成功诱导出GST-SnRK1.1、GST-FD和GST-FD-T282A蛋白。利用GST纯化介质纯化获得了84 k Da的GST-SnRK1.1蛋白以及58 k Da的GST-FD与GST-FD-T282A融合蛋白;利用体外磷酸化体系证实SnRK1.1能够磷酸化FD,不能磷酸化突变的FD-T282A。研究结果为进一步解析SnRK1.1通过磷酸化转录因子FD参与开花途径调控的机制奠定了良好的基础。  相似文献   
975.
976.
977.
Acute mountain sickness (AMS) is the greatest challenge of military medicine and wilderness medicine, as the increasing populations of entering Tibet and others who rapidly ascend to high altitude. AMS is considered as a kind of vascular dysfunction and disequilibrium of body fluid diseases induced by environmental stress. Studies reveal that endogenous nitric oxide (NO), a predominant endogenous vessel dilator, plays a crucial role in the pathogenesis of AMS. The decreased production and blocked delivery of NO cause dysfunction of the vascular system in hypoxic situations. Subsequently, AMS develops under the facilitations of alterations in brain and pulmonary blood vessels. NO or L-arginine (the precursor of NO) can also be used to prevent and treat AMS. This review will summarize the progress on the roles of NO in the pathogenesis, pathophysiology, treatment and prophylaxis of AMS.  相似文献   
978.
海飞  琚园园 《北方园艺》2012,(5):148-150
调查了河南省多种经济作物根结线虫病的发生情况,对其采样进行了种类鉴定研究。针对烟草根结线虫分别进行盆栽试验、田间小区试验和田间示范应用,系统考察了一种由多种中草药材料混合而成的新型植物源线虫速杀剂对烟草根结线虫病的防治效果,为研发低毒性、低残留杀线剂、提高农产品的质量安全性提供科学依据。  相似文献   
979.
瘦素受体(leptin receptor,LEPR)在机体的体质量平衡、造血、生殖、血管生成和免疫过程中发挥着重要作用。为进一步了解LEPR基因在苏钟猪脂肪沉积调控中的作用机制,本研究利用Real-time PCR方法和Western-blot方法分析该基因在12头苏钟猪中5个脂肪易沉积组织(心脏、肝脏、肾脏、背膘和眼肌)RNA和蛋白水平的表达谱信息。结果表明:LEPR的mRNA在这5种组织中均有表达,其在各组织中的mRNA表达丰度表现为:背膘〉眼肌〉心脏〉肝脏〉肾脏,其中在背膘的表达量极显著高于其他几种组织(P〈0.01);LEPR蛋白在这5种组织中也均有表达,其中在心脏中的表达量最高,显著高于其他组织(P〈0.01),且在公猪组织的表达量显著高于母猪组织(P〈0.05);另外,LEPR第18外显子在苏钟猪群中检测到3个高突变率的SNPs。LEPR对苏钟猪的背膘、肌肉、心脏、肾脏、肝脏等组织的脂肪沉积有重要影响,是苏钟猪肉质改良育种中潜在的重要候选基因。  相似文献   
980.
Mulching is considered a desirable management technology for improving and stabilizing agricultural crop production. The aim of the present study was to evaluate the effect of different mulching practices on hot pepper (Capsicum annuum L.) performance in terms of leaf photosynthetic capacity, photosynthetic light response (PLR) curves, and growth parameters, under greenhouse conditions. Consequently, field experiments were conducted during the 2011 and 2012 growing seasons in Northwest China using four types of mulching practices (without mulch; wheat straw mulch; plastic film mulch; and combined mulch with plastic film and wheat straw). The results showed that mulching increased the leaf net photosynthesis rate, stomatal conductance to water vapor, intercellular CO2 concentration, water-use efficiency, and transpiration rate. Mulching significantly affected the PLR curves, and important parameters (such as the apparent quantum yield, maximum net photosynthetic rate, light compensation point, and light saturation point) were all improved under combined mulching conditions when compared with other mulching practices. Therefore, it is inferred that hot pepper leaf photosynthetic capacity and light-use efficiency were significantly improved under combined mulching, and thereby the combined mulching is recommended for hot pepper cultivation in greenhouses due to working well to facilitate soil condition (moisture and temperature), plant growth, and marketable photosynthetic characteristics.  相似文献   
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