水稻光温敏核不育系的温敏期研究

TEMPERATURE-SENSITIVE STAGE OF PHOTOPEKIOD AND THERMOPERIOD SENSITIVE GENIC MALE-STERILE LINE IN RICE

以农垦５８Ｓ为基因供体转育的ｗ６１５４Ｓ，Ｋｓ－９，Ｎ１２Ｓ，Ｎ１５Ｓ，Ｎ１８Ｓ５个籼稻光温敏核不育系，于１９９１～１９９３年在广州自然条件下观察了它们的育性变化，对温度诱导其育性转换规律进行了相关，多元回归及通径分析。结果表明：１．不同的不育系，其温敏性越强不育系温敏期越长。同一不育系，日最低温温敏期最长，日均温其次，日最高温最短。２．不同不育系各温度因素对花粉育性的影响不同。有的以日最低温影响最大；有的以日均温影响最大。各温度因素之间的作用有的相差悬殊；有的则相差较小。３．温敏期内通常有２～３个强温敏时段，它们因不育系不同而分布的区段不同；同一不育系，日最低温、日均温、日最高温的强温敏时段分布也有差异。

indica lines,W 61545,Ks-9,N128,N15S and N18S,derived from Nong ken 58S,were studied under natural conditions in Guangzhou uring 1991～1993.The fertilityvariation induced by temperature was analysed by correlation regression and pathanalysis.The result showed that:l.The length of the temperature-sensitive stage wasdifferent among various sterile lines,and the stronger the thermosensitivity thelonger the thermosensitive stage. For the same line,the longest thermosensitivestage occurred at the daily minimum temperature,secondly at the daily averagetemperature,thirdly at the daily maximum temperature.2.The effects of temperaturefactors on pollenfertility differed among various lines. Minimum temperature was mostimportant to some lines,but to the others,average temperature was,3.In general,there were 2～3 stronger substages in a thermosensitive stage. The distributions ofthe substages depended on various lines. For the same line,the distribution of sub-stages were different among daily minimum temperature,daily average temperature anddaily maximum temperature.