滇1型粳稻不育系和保持系的花时特性研究

Studies on Flowering Time Traits of Japonica CMS-D1 Lines and Their Maintainer Lines in Rice

观察了113个育性稳定的滇1型细胞质雄性不育系(A)及其保持系(B)的花时特性,结果表明,不育系与保持系的单穗花期为5～10 d,大部分材料为6～7 d;不育细胞质对花时有影响,94%的不育系花时较其相应保持系晚,平均晚约40 min;根据不育系和保持系的花时早晚、花时相遇情况等将其分为4种类型。提出滇1型粳稻不育系优良花时性状的2个评价指标:一是不育系的始盛花时间不迟于14:00;二是不育系的理论有效相遇颖花率在70%以上。

The flowering time traits of 113 japonica Dian 1 type CMS （CMS-D1） lines and their maintainer lines were surveyed. The results showed that the flowering period of a single panicle varied from 5 to 10 days among the tested CMS-D1 lines and their maintainer lines but from 6 to 7 days for most of them. It was found that the male sterile cytoplasm of Dian 1 type had a distinct effect on flowering time. 94% of the CMS-D1 lines had a later initial blooming time than their corresponding maintainer lines, with an average of delayed initial blooming time at about 40 minutes. Based on the blooming time and flowering synchronization, the CMS-D1 lines were grouped into four types. Furthermore, two indices were proposed for evaluation of desirable flowering time traits of CMS-D1 lines. One was the initial full blooming time no later than 14：00 and the other was the theoretical rate of effectively syn- chronized spikelets over 70%.