Abstract: Xiu-Shui 117, a japonica cultivar and IR58, an indica cultivar were discovered to show compatibility in indica/japonica crosses. The spikelet fertility of F₁, hybrids of 6 japonica/indica crosses, i.e. Xiu-Shui 117/IR58, Xiu-Shui 117/Er-Jiu-Feng, T8340/IR58, Shuang-Bai A/IR58, Nong-Liu 209A/IR58 and Liu-Qian-Xin A/IR58 was 85.9%, 88.4%, 81.1%, 76.5%, 74.5%and67.0%, respectively. The F₁ hybrid of Xiu-Shui 117/IR58. greatly exceeded the higher parents in several traits, such as plant height, panicle length, the number of'spikelets per panicle and the grain yield per plant, etc. The compatibility of this cross was also present in the F₂, and backcross generations. The results suggested that there may be some varieties which would show compatibility in indica/japonica crosses in both subspecies, but the extent of their compatibility might be different. Some problems were discussed about utilizing the heterosis of the F₁ hybrids between indica and japonica.

Key words: indica-japonica rice hybridization, Compatibility, Spikelet fertility, Heterosis

摘要： 发现粳稻品种秀水117和籼稻品种IR58分别表现亚种间杂交的亲和性。秀水117与IR58、二九丰的杂种一代结实率分别为85.9%和88.4%;IR58与T8340及粳型不育系双百A、农六209A和六千辛A的杂种一代结实率分别为81.1%、76.5%、74.5%和67.0%”秀水117/IR58”的F_1在株高、穗长、每穗粒数和单株稻谷产量等性状上均存在很强的正向超亲优势。该组合的亲和性在F_2及回交世代中仍可表现。试验结果表明,在籼、粳稻内各存在着亚种间杂交的亲和性材料,但其亲和性的表现范围可以不同。讨论了籼粳稻亚种间杂种优势利用的一些问题。

关键词: 籼粳稻杂交, 亲和性, 杂种结实率