小麦中国春-Synthetic 6x代换系穗花分化与耐旱基因的染色体定位

Chromosomal Localization of Genes Associated with Spikelet Differentiation and Drought Tolerance in Chinese Spring (recipient)/Synthetic 6x (donor)

【目的】通过对不同水分处理条件下小麦代换系的穗花发育进程和产量性状研究,确定控制小麦穗花发育的主效应染色体,并对耐旱基因进行染色体定位。【方法】以小麦CS-Synthetic6x整套染色体代换系及其亲本为材料进行干旱胁迫处理,对穗花分化过程进行观察,并对其产量性状分析研究。【结果】各代换系的穗花发育过程与亲本较为一致,都能正常通过穗原基和花原基分化两个阶段。在正常灌水条件下,2B代换系与父本Synthetic6x发育同步,分化最慢,7D次之,其它代换系发育较快,与母本中国春基本同步;在干旱胁迫条件下,2D代换系穗花分化较为缓慢,远远落后于中国春和其它代换系。且2D代换系每穗粒数、单穗粒重、千粒重等产量性状的抗旱系数均显著或极显著高于中国春。【结论】延缓穗花分化进程的主效基因可能位于2B和7D染色体上;耐旱相关基因可能位于2D染色体上。

[Objective] Chromosome substitution lines between Chinese Spring and Synthetic 6x under different water treatments were used to locate the gene controlling spikelet progress and drought tolerance. [Method] A series of spikelet differentiation progress were observed and several yield components were studied. [Result] The results indicated that spikelet progress of various substitution lines and that of parents, including spike and flower primordium differentiation periods, were alike. Under normal irrigation, 2B substitution line is the latest in the progress of spikelet differentiation, 7D substitution line is the second, while Chinese Spring and other substitution lines are the earliest. Under drought condition, the spikelet differentiation progress of 2D substitution line is much slower than Chinese Spring and other substitution lines. The drought resistance coefficient （DRC） of the grain weight per spike, kernel number per spike and 1000-grain weight of 2D substitution line are significantly different from Chinese Spring. [Conclusion] It is concluded that the genes inhibiting spikelet differentiation may be located on 2B and 7D chromosomes, and that the gene of drought tolerance may be located on 2D chromosome.