SSR标记遗传距离与水稻籼粳衍生系杂种优势的相关性分析

摘要

[Objective] The study was used to analyze on correlation between heterosis and genetic distance based on Simple Sequence Repeat Markers.[Method] Genetic diversity among 20 derived lines of indica-japonica hybrid rice was studied using the simple sequence repeat (SSR) markers,and relationship between genetic distance based on SSR markers and yield heterosis was analyzed using the materials consisted of 20 parents and 96 F1 hybrids with a 12 * 8 diallel crossing design.[Result] (i)The plant height,panicle length and 1000-grain weight showed positive heterosis with less variation range;The grain number per panicle and the seed setting rate showed positive heterosis with relatively larger variation range,and the unbalance existed in the Indica-japonica cross derived lines;The effective panicle number showed negative mid-parent heterosis.(ii) The parental of 96 F1 hybrid at the genetic distance for 0.2547-0.5660,the correlation between heterosis of F1 seed setting rate,1000-grain weight and GD has negligible effect,the correlation between heterosis of effective panicles and GD has no significant correlation;However,the correlation between heterosis of plant height,heterosis of panicle length,heterosis of total spikelets per panicle,heterosis of spikelets per panicle,yield per plant of spikelets per panicle and GD appeared to be significant at P ＜ 0.01.[Conclusion] At the parental genetic distance for certain range,heterosis and genetic distance has significant correlation.%[目的]探讨分子标记遗传距离与杂种优势的相关性.[方法]利用SSR标记分析8个水稻不育系和12个籼粳亚种间杂交衍生系的遗传多样性,按照不完全双列杂交(NCII)获得96个杂交组合,分析亲本间遗传距离与其主要产量性状杂种优势表现.[结果]①籼粳衍生系杂种后代株高、穗长和千粒重表现为正向优势,变异幅度较小;每穗实粒数和结实率虽表现相对不平衡,但均为较强正向优势;有效穗数表现较弱,为负向中亲优势.②籼粳衍生系杂种F1在SSR标记遗传距离0.2547～0.5660,穗长、株高、每穗实粒数、每穗总粒数、单株产量超亲优势与遗传距离极显著相关,与F1结实率、千粒重、有效穗数的杂种优势相关不显著.[结论]在一定遗传距离范围内,SSR标记亲本遗传距离与杂种优势之间有一定的相关性.