中文摘要：

阐明粳稻细胞质雄性不育系开花习性与异交率之间的关系,是选育高异交率粳稻不育系的重要基础。在对284份滇一型粳稻细胞质雄性不育系的自然异交率检测和部分不育系开花性状观测的基础上,通过相关分析和开花习性的精细比较,发现粳稻不育系间自然异交结实率变化幅度较大,大多数粳稻不育系的自然异交率都比较低,但同时也鉴定出少量高异交率的不育系。相关分析发现颖花的开颖角度与粳稻不育系的自然异交结实率呈显著正相关。通过对3个不育系开花性状的精细观察分析,显示了开花集中度是影响粳稻不育系异交率的重要因素。在粳稻不育系的育种实践中应该加大对不育系开颖角度和开花集中度的选择,以提高粳稻不育系的异交结实率。

英文摘要：

Clarifying the relationship between the flowering characters and the outcrossing rate of japonica riceCMS lines is the important foundation for breeding japonica rice CMS lines with high outcrossing rate.Basedon the evaluation of the outcrossing rate of 284 Dian-type 1 CMS lines and the flowering charactersobservation in parts of CMS lines,the correlation analysis and fine comparison were conducted.The resultsindicated that the outcrossing rate was greatly different among the japonica rice CMS lines,and most of thelines possessed relatively low outcrossing rate,but a few of high outcrossing rate lines were also identified.Thecorrelation analysis showed that the floret opening angle（FOA） was significantly and positively correlated withthe outcrossing rate.After fine observation of the flowering habits of three CMS lines,the results showed thatthe concentration of florets flowering time（CFFT） was the main factor affecting outcrossing rate of japonica riceCMS lines.In conclusion,FOA and CFFT should be highlighted in breeding activity to improve the outcrossing rate of the japonica rice CMS lines.