水稻远缘外源DNA导入创制新资源研究进展

通过远缘杂交的方法,将异源植物的优良基因转移到水稻中,打破不良性状连锁,实现优良性状结合。研究结果表明,转基因后代的性状变异深刻,类型丰富多样,其中农艺性状上的优良变异较多,因而在多抗、高产、优质育种上取得了较显著的进展。就国内水稻远缘杂交研究的供体、杂交方法、后代表现以及在育种上应用情况作了全面阐述。对外源基因导入的过程以及创制新资源和选育新品种研究进展情况进行了详细介绍。认为远缘杂交技术对引进外源基因,丰富水稻基因库,创造新资源行之有效,且方法简便易行。在转基因方法上,认为复态导入法可以更好地保持供体DNA的完整性,更有利于多基因的转入。     

Experimental Study on Mechanical Behavior of Y-Shaped Transfer Joint Used in Obliquely Crossing Lattice

In order to study the mechanical behavior of the Y-shaped joints in oblique crossing lattice, two 1:3 scale models of the Y-shaped joints which are respectively applied symmetrical and asymmetrical axial force in experiment processes are tested, and the corresponding numerical simulations are carried out by using ABAQUS software. The stress state and deformation behavior of concrete-filled square tube column and steel beam rigid joint with internal diaphragms for high-rise structure are analyzed. The results of the test and the numerical simulation consistently show that in the loading process, the deflection of the joint core is insignificant and a good connection, the joint core is able to deliver the internal force effectively before the damage of the oblique column and meet the requirement of “strong joint and weak column”.     

利用SNP标记进行水稻品种籼粳鉴定

亚洲栽培稻(Oryza sativa L.)分为籼、粳2个亚种,随着杂交水稻的发展、种间杂种优势的利用,籼粳之间的界限变得越来越模糊。本研究利用3000份水稻种质资源信息,通过计算约2000万个单核苷酸多态性(single nucleotide polymorphism, SNP)位点的SNP-index值,进行籼粳特异SNP位点筛选,最终得到4084个籼粳特异SNP位点(4k-SNP);同时确定以籼粳指数作为水稻品种籼粳鉴定的指标。研究进一步采用大规模简单随机取样等统计分析方法对籼粳特异位点进行数据降维处理,将4k-SNP精简至40个SNP位点(40-SNP),用于水稻籼粳鉴定。为了验证40-SNP的籼粳鉴定效果,本研究一方面利用水稻生产上推广的82份选育品种,对40-SNP籼粳鉴定结果与4k-SNP鉴定结果进行比较,结果发现40-SNP与4k-SNP得出的粳型指数非常接近,相关系数为0.99;另一方面利用全球6类型(indica、aus、rayada、aromatic、tropicaljaponica、temperatejaponica)水稻品种共49份材料,对40-SNP籼粳鉴定...