光(温)敏核不育水稻的育性和开花习性研究

在合肥地区自然条件下,对7个光(温)敏核不育系的育性稳定性和育性转换特性及开花习性进行了研究。结果表明:粳型7001S、N5088S和31111S不育性稳定,不育期花粉败育率、自交结实率分别为99.82—99.96%、0.00—0.03%,育性转换明显,转换期自9月5—6日先后开始,可育期花粉败育率27.82—41.72%,自交结实率20.92—44.00%,作为两系杂交稻的母本应用可行。粳型N5047S、籼型W7415S基本具有与上述3个粳型核不育系相似的育性稳定性和育性转换特性,用作母本基本可行。籼型W6154S、8801S不育期因花粉母细胞减数分裂期低温,出现不同程度不同次数的育性波动,应用风险大。粳型7001S、N5088S、31111S和W6154S开花完全(颖花开花率较高),张颖时间较长或中,花时高峰早且集中,或花时分散但午前花率较高,利于制种,N5047S、W7415S、8801S开花率低,盛花时迟或颖花张颖时间短,制种困难。

Studics on the Fertility and Flowering Habits of Photoperlod(Thermo-) Sensitive Genic Male-Sterile Rice.

Using seven indica or japonica photoperiod (thermo-) sensitive genie male-sterile lines (7001S, N5088S, N5047S, 31111S, W6154S, W7415S and 8801S) as the experimental material, under natural conditions at Hefei in 1990, the fertility stability and fertility change characters of thern were investigated according to the pollen sterility (%) and seed set (%),and the flowering habits of them were observed according to spikelet flowering (%), stigma extrusion (%), peak of panicle flowering stage, peak of spikelet flowering time, and triped spikelet time. The results are as follows: (1)The sterility of 7001S、 N5088S and 31111S showed stable. The pollen sterility (%) and seed set (%) were 99.82～99.96% and 0.00～0.03% in sterile stage, respectively. The fertility change was obvious, and the fertility change stage began on September 5 or 6. In fertile stage, the pollen sterility (%) existed 27.82～41.72%, and the seed set (%) 20.92～44.00%. It was available that the three photoperiod sensitive genic male-sterile lines were used as female parents of two-line hybrid rice. (2)The fertility stability and fertility change character of N5047S and W7415S were similar to above photoperiod sensitive genie male-sterile lines. They could be basically used as female parents. (3)The fertility of W6154S and 8801S presented fluctuation in different degree and time in sterile stage. It would be full of hazard to apply them. The low temperature in pollen mother cell reduction mitosis phase could caused the fertility fluctuation. (4)7001S, N5088S, 31111S and W6154S flowered completely (spikelet flowering 76.69～92.16%). The triped spikelet time remained longer or intermidiate (78.06～305.45 minutes). The peak of spikelet flowering. time came early and concentratal, or the percentage of spikelet flowering before noon was higher although flowering time existed dispersive. So the four photoperiod (thermo-)sensitive genic male-sterile lines had advantage of hybrid seed production. (5)The spikelet flowering(%) of N5047S, W7415S and 8801S showed lower (37.28～63.33%), and the peak of spikelet flowering time came late or triped spikelet time insisted short. It would be difficult to aprily the three photoperiod (thermo-)sensitive genic male-sterile lines to hybrid seed productionOwerall, the sterility of 7001S, 31111S and N5088s standed stable, the fertility change character moved obvious, and the flowering habits were better. They belong to excellent photoperiod sensitive genic male-st(?)ile lines.