Abstract: Comparison of seed setting rate, plant height and Cheng's morphological traits were made between the F₂ progeny of indica japonica hybrids 02428/Pei'ai 64 and Taichung 65/Teqing. Results showed that there existed resemblance normal distribution in plant height and the distribution was not related with the seed setting rate and plant height in F₁ progeny, suggesting that there was no gametic selection for the plant height in the F₂ progeny of indica japonica hybrids. Average seed setting rates of the F₂ and F₁ populations were equal in the rcombination of 02428/Pei'ai 64 with excellent compatibility, but the remarkable increase of seed setting rate from F₁ to F₂ in Taichung 65/Teqing, indicating that gametic selection only took place in indica-japonica crosses with low compatibility, and null or little in the hybrids with high compatibility. There were many intermediate types of leaf hairness, color of hull at heading and length of the first and second panicle internode, these Cheng's morphological traits were normal distribution, also, there were a little intermediate types in hull hairness and phenol reaction with bi-peak distribution, and the ratios of lenth to width of grain were inclined to japonica types obviously and these traits showed a skewed distribution in F₂ population. Although Cheng's morphological traits in F₂ populations had inconsistent distribution types, Cheng's morphological traits index was normal distribution, showed that intermediate types, i.e. indicalinous or japonicalinous, were primary in F₂ population.

Key words: rice, indica-japonica crosses, genetic effect, generations, distribution, morphological traits, seed setting rate, plant height

摘要： 比较了02428/培矮64和台中65/特青两个不同的籼粳交组合F2结实率、株高和几个程氏分类性状的分布。结果表明：（1）两个组合的株高呈现相似的正态分布，不受其F1结实率和株高的影响，说明F2株高不存在配子选择问题；在杂交亲和性较好的02428/培矮64中，F2的平均结实率与其F1的结实率几乎相等，而台中65/特青结实率则表现为由F1到F2增加的趋势，说明配子选择在亲和性较好的杂种中很少或不存在，而在亲和性相对较差的组合中存在。（2）在程氏分类性状的分布中，叶毛、抽穗时稃色和第１~２穗轴节长等存在大量的中间类型，表现明显的正态分布，稃毛和酚反应虽呈双峰分布，但仍然存在少量的中间类型，而谷粒长宽比则表现极端的偏斜分布，明显地偏向粳型。虽然各分类性状表现不同的分布类型，但程氏分类指数表现出正态分布，即偏籼偏粳的中间型占绝大多数。关键词

关键词: 水稻, 籼粳交, 遗传效应, 世代, 分布, 分类性状, 结实率