陆地棉分子标记辅助轮回选择聚合育种研究 Ⅳ．纤维比强度选择效果及对其他品质性状的影响

为了改良现有陆地棉栽培品种的纤维品质，通过MAS M2、M1，表型选择P2、P1，分子标记结合表型选择MP1、MP2群体和基础群体C0，经两年的研究比较发现，第二轮标记选择群体M2的比强度均高于其他群体，选择响应值达正值。在两轮选择中，均是标记选择高于表型选择。利用本实验室筛选的2个与纤维比强度主效QTL位点连锁的分子标记对

Pyramid Breeding by Markerassisted Recurrent Selection in Upland Cotton Ⅳ.MAS Efficiency for Fiber Strength and Effects on Other Fiber Qualities

To improve the fiber quality of upland cotton cultivars, seven selection populations were developed, namely C_0, P_1, M_1, MP_1, P_2, M_2, MP_2. Compared to the results of two years, some conclusions were acquired as follows: the M_2 population produced significantly greater fiber strength than all other populations and obtained positive selection response. Within the populations of two cycles selection, all marker-assisted selection's fiber strength was greater than that of phenotypic selection. The efficiency of marker-assisted selection was studied through two markers associated with the major QTL for fiber strength.The present results revealed that the two markers selection gained a significant difference and fiber strength was increased greatly. The fiber strength means of populations with and without SSR1521 marker were 32.03 cN/tex and 30.82 cN/tex, the fiber strength means of populations with and without RAPD ubc301 were 31.19 cN/tex and 29.83 cN/tex, as the two markers were used simultaneously, the means were 31.66 cN/tex and 30.80 cN/tex, respectively. All the differences of them were significant. As fiber strength was increased by marker-assisted than phenotypic selection, there were significant increases in elongation and micronaire, but no significant changes in length and uniformity among all populations.