水稻籼粳中间型RIL系主要农艺性状杂种优势分析

分析了遗传背景相同的籼粳中间型重组自交系（RIL）9个品系与5个籼、偏籼型光温敏核不育系杂交的F1主要农艺性状的杂种优势．结果表明：9个农艺性状均表现为正向超亲优势，以单株产量、穗实粒数、株高和穗总粒数表现的优势较强，有效穗数、结实率和千粒重表现的优势较弱；F1单株产量仅与父本穗长呈显著负相关，而与杂种有效穗数、穗实粒数、结实率和千粒重呈极显著和显著正相关；F1单株产量的超亲优势与父本单株产量、有效穗数、结实率均呈极显著负相关，与父本抽穗天数和千粒重却呈显著负相关，而与杂种的抽穗天数、有效穗数、穗实粒数、结实率和千粒重优势呈极显著正相关．亚种间杂交稻超高产的获得关键在于要协调好产量目标、亲本产量构成因素和其杂种优势三者的关系．

Analysis on Heterosis of Main Agronomic Traits of Inter Indica-japonica Type RILs in Rice

The heterosis of the main agronomic traits were investigated to the Inter indica-japonica F1, which derived from five PGMS lines crossed with nine recombinant inbred lines （RILs） of the same one cross. The results showed that all the nine agronomic traits have positive heterosis, of which, grain yield per plant, filled grains per panicle, plant height and spikelets per panicle are strongly, while panicles per plant, seed setting rate and 1000- grain weight are weakly. Grain yield per plant of F1 exhibits significant negative correlation with panicle length of male, and significant or highly significant positive correlation with panicles per plant, filled grains per panicle, seed setting rate and 1000-grain weight of F1. However, the over-parent heterosis of grain yield per plant is highly significant or significant negative correlation to grain yield per plant, panicles per plant, seed setting rate, days to heading and 1000-grain weight of mail, while highly significant positive correlation with the heterosis of days to heading, panicles per plant, filled grains per panicle, seed setting rate and 1000-grain weight of F1. The key way for breeding a super-hlgh yield hybrid of subspecies is the optimal relationship among the objective yield, the yield components of parents and the heterosis.