水稻台中65与其花粉不育近等基因系的杂种F_1的裂药性研究

Studies on the Anther Dehiscence in F_1 of Hybrids between Taichung 65 and Its F1 Pollen Sterility Near Isogenic Lines

以台中65及其7个F1花粉不育近等基因系为材料,对水稻亚种间杂种F1裂药性及其与小穗育性的关系进行了研究。结果表明,杂种F1的裂药性受花粉不育基因互作控制。不同杂合座位内等位花粉不育基因互作导致杂种F1花药不开裂的程度不同,S-b座位导致杂种F1部分花药不开裂;不同杂合座位间非等位花粉不育基因互作明显降低杂种F1的裂药程度;杂种F1中含杂合花粉不育基因座位数越多,其裂药指数越小,裂药程度越低,含三个杂合花粉不育基因座位的杂种F1裂药指数为2.27,35.3%的花药不开裂。杂种F1花药不开裂的原因随其所含的杂合花粉不育基因座位种类和数目不同而异。杂种F1裂药程度的下降显著减少落在其柱头上的花粉总数和萌发的花粉数。杂种F1裂药指数和结实率呈极显著的正相关关系。

Japonica rice cultivar, Taichung 65, and its seven F1 pollen sterility near isogenic lines were employed to study the impact of pollen sterility locus on anther dehiscence in hybrid F1 using the anther dehiscence index asindicator. The results showed that the anther dehiscence trait was controlled by genic interaction of pollen sterility loci. Allelic interaction at different pollen sterility loci resulted in different degree of anther indehiscence in hybrid F1. Allelic interaction at S-b locus resulted in part of anther indehiscence in hybrid F1. Genic interaction between pollen sterility loci obviously decreased the anther dehiscent ability. The more heterozygous pollen sterility loci the hybrid F1 had, the worse anther dehiscence the hybrid F1 was. The hybrid of T65×TISL245 had three heterozygous pollen sterility loci, its anther dehiscence index was only 2.27 and the anther dehiscence ability was worst. The main causes resulting in poor anther dehiscence in hybrid F1 were different with the kind and the number of heterozygous pollen sterility loci. The anther dehiscence markedly decreased the total number of pollen grains and the number of pollen grains germinated on stigma. The positive correlation between anther dehiscence index and spikelet fertility was extremely significant.