两个籼粳交杂种F2几个重要性状的分布

比较了 0 2 4 2 8/培矮 6 4和台中 6 5 /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 0 2 4 2 8/培矮 6 4中 ,F2 的平均结实率与其 F1 的结实率几乎相等 ,而台中 6 5 /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。

Distribution of the Classification Traits in the F2 Progeny of Two Crosses of Indica/Japonica in Rice (Oryza sativa)

Comparison of seed setting rate, plant height and Cheng's morphological traits were made between the F 2 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 F 1 progeny, suggesting that there was no gametic selection for the plant height in the F 2 progeny of indica japonica hybrids. Average seed setting rates of the F 2 and F 1 populations were equal in the recombination of 02428/Pei'ai 64 with excellent compatibility, but the remarkable increase of seed setting rate from F 1 to F 2 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 length to width of grain were inclined to japonica types obviously and these traits showed a skewed distribution in F 2 population. Although Cheng's morphological traits in F 2 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 F 2 population.