知识与财富的链接
穗下节间长决定着玉米的穗位高和株高, 而株高和穗位高与产量、抗倒伏性等重要农艺性状密切相关。玉米穗下第7、第8、第9节间长对穗位高具有决定作用, 与其他农艺性状相比, 对穗下节间长的遗传基础了解甚少。因此, 研究玉米穗下节间长的遗传基础, 对玉米育种有重要意义。本研究以lx9801为受体亲本, 昌7-2为供体亲本通过连续回交和自交所构建的一套包含260份染色体单片段代换系的群体为研究对象, 通过两年两环境的表型鉴定, 并结合基因型数据对第7、第8、第9节间长和穗位高的QTL进行定位。共检测到18个第7节间长QTL, 23个第8节间长QTL和17个第9节间长QTL, 其中8个QTL是为第7、第8、第9节间长所共有。穗位高定位到的20个QTL中, 有12个(60%)与第7、第8、第9节间长QTL共定位。说明第7、第8、第9节间长与穗位高有着共同的遗传基础, 节间长也是穗位高的重要构成因子, 决定着玉米的株高和穗位高。
The under-ear internode length determines maize plant height and ear height, which are two agronomic traits associated with yield and lodging resistance. The lengths of the 7th, 8th, and 9th internode play a decisive role in ear height. Compared with other agronomic traits, there is little knowledge for genetic basis of under-ear internode length. Thus, exploring the genetic basis of internode length plays an important role in maize breeding. In this study, a set of 260 chromosome segment substitution lines (CSSLs), using Chang 7-2 as the donor parent and lx9801 as recipient parent, was constructed and used to map QTLs for the 7th, 8th, and 9th internode length and ear height at two-environments in two years. In total, 18, 23, and 17 QTLs were detected for the 7th, 8th, and 9th internode length, respectively. Among them, eight QTLs were simultaneously detected for the 7th, 8th, and 9th internode length. For ear height, 20 QTLs were detected, 12 (60%) of these 20 QTLs were found to co-localize to the 7th, 8th, and 9th internode length. The results indicated that length of the 7th, 8th, and 9th internode and ear height have same genetic basis. Furthermore, length of the 7th, 8th, and 9th internode are important components of ear height and also determining the plant height and ear height in maize.
