杂交粳稻与纯系粳稻收获指数比较研究

Comparative studies on harvest index between hybrids and pure lines in japonica rice (Oryza sativa L.)

在南京和洪泽两地研究了５个杂交粳稻及其亲本和３个纯系粳稻的生物量、稻谷产量和收获指数。结果表明，当杂交粳稻的亲本包括在纯系粳稻内，杂交粳稻的生物量、稻谷产量极显著地大于纯系粳稻，而收获指数相反；当亲本不包括在内，杂交中熟中粳的生物量虽极显著地大于生产上栽培的纯系粳稻，但因收获指数相反，两者平衡后，稻谷产量无显著差异。生产上栽培的纯系粳稻生物量、稻谷产量和收获指数均极显著地大于杂交粳稻亲本。纯系矮秆粳稻的收获指数极显著地大于中秆粳稻，生物量极显著地小于中秆粳稻，稻谷产量无显著差异。粳稻保持系的生物量、稻谷产量极显著地大于粳稻恢复系，收获指数相反。

Biomass, grain yield (unhulled) and harvest index of 5 japonica hybrids, their parents and 3 japonica pure lines were studied in Nanjing and Hongze. As shown by the results, the biomass and grain yield of hybrids were significantly (α=0.01, the same hereafter) greater than those of pure lines when parents of hybrids were included in the pure lines, but reversed in harvest index. However, when parents of hybrids were not included, there was no significant difference in grain yield between middle mid hybrids and pure varieties cultivated, although biomass of the former was greater significantly. The biomass, grain yield and harvest index of pure lines cultivated were greater than those of parents of hybrids significantly. The harvest index of dwarf pure lines was significantly greater than that of middle height pure lines, but reversed in biomass, as a result there was no significant difference in grain yield between them. The biomass and grain yields of maintainers were significantly greater than those of restorers, but reversed in harvest index.