六倍体燕麦抗麦二叉蚜种质创制与基因发掘

基于麦二叉蚜是一种可塑性强、易克服单基因抗性的多型害虫，利用具有丰富抗逆基因的六倍体野生燕麦创制抗蚜种质需在明确当地麦二叉蚜生物型的结构组成后才有实际意义。因此，本研究在现有工作基础上，首先用单基因鉴别寄主法进行甘肃南部湿润、中部干旱和西部高寒阴湿区麦二叉蚜的生物型鉴定研究；其次用盆栽网罩释放蚜虫法进行近免疫野生燕麦和高抗栽培品种对优势生物型麦二叉蚜的排趋性、抗生性和耐害性评价研究；再用近免疫野生燕麦和高抗栽培品种与高感品种"定莜4号"进行杂交和回交，F1、F2代群体抗性遗传分析和SSR标记的基因定位研究。旨在明确甘肃不同生态区麦二叉蚜的生物型结构组成，阐明六倍体野生燕麦与栽培品种抗蚜机制的差异性，发掘新的抗蚜种质和抗蚜基因。这项研究结果将为燕麦抗蚜种质创制指明方向，为野生燕麦成为种质资源、选育兼性抗蚜品系技术研究提供科学依据，解决单基因抗蚜品系应用使麦二叉蚜分化新生物型的科学问题。

It makes meaningful sense to create greenbug-resistant germplasm with hexaploid wild-oats with multi-resistant genes only when structural composition of local biotypes was identified on the bases that greenbug is a category of strongly plastic and polytypic pests which can overcome some varieties with single resistance gene. Therefore, we will firstly carry out biotypical identification in southern humid climates, central dry climates and western cold climates in Gansu, we will secondly carry out their antixenosis, antibiosis and tolerance tests against prevalent biotype in nearly immune wild-oats and highly resistant cultivated-varieties, we will thirdly carry out crossing and backcrossing nearly immune wild-oats and highly resistant cultivated-varieties with highly suceptible variety " Dingyou 4", identification of greenbug resistance in F1 and F2 progeny, analysis of genetic development, gene mapping by SSR molecular marker technique. The objectives aim at mastering biotypes in various ecotypes in Gansu, clarifying differences in greenbug resistance mechanism between wild oats and cultivated varieties, finding new greenbug-resistant germplasm and greenbug-resistant gene and positioning it in chromosome. These research results will not only define our research directions for creating greenbug-resistant germplasm in oats, but also provide a scientific basis that wild oats will become genetic resources, breed facultative varieties with resistance to greenbug, availably solve the problem that biotypical differentiations of greenbug was accounted for growing varieties with single resistance gene.