三个籼型光温敏核不育系杂交F_1和F_2代的不育性研究

STUDY ON STERILITY OF F_1 AND F_2 PROGENIES OF THREE INDICA PHOTO-THERMO-SENSITIVE GENIC MALE-STERILE LINES

8902S是光敏性强、可育临界温度较高的光敏不育系，2877S是光敏性强、可育临界温度较低的光敏不育系，而2558S是光敏性弱、可育临界温度低的温敏不育系，它们都是由农垦58S衍生而来的籼型核不育系。这三个不育系杂交，F_1在长光照、偏低气温下均表现稳定的不育性，表明三个亲本的不育主基因是等位的，F_1可育临界温度与低的亲本相近或更低．光敏不育系89025与2877S杂交，F_1与亲本一样，光敏性强；8902S和2877S与温敏不育系25585杂交，F_1表现双亲的中间型，光敏性中等．2877S与25585杂交F_2代不育株，在长光照、偏低气温下表现败育程度高，在短光照下绝大多数表现可育，且其中很多结实率病，光敏性强．还讨论了农垦58S衍生不育系不育主基因的等位性和实用型光敏核不育系的选育方法．

8902S is a photo-sensitive genic male-sterile (PGMS) line which has strong photo- sensitive male-sterility (FSMS) and relatively higher critical fertilith temperature point (CFTP). 2877S is a PGMS line which has strong PSMSand relatively lower CFTP. 2558S is a thermo-sensitive genic male-sterile (TGMS)line which has weak PSMS and low CFTP. They are all indica genic male-sterile (GMS) lines derived from the japonica PGMS line Nongken 58S. F1 progenies of the crosses between the 3 lines all espressea able sterility under long day and relatively lower temperature, which indicates that sterile major-genes of the 3 lines are allelic, and the F1 is similar in CFTY to their low CFPT parents. The F1 of the cross between PGMS lines 8902S and 2877S has as strong PSMS as its Fatents did, and F1 between 8902S or 2877S and a TGMS line 2568S has medium PSMS which is medium type of their parents. Sterile plants in F2 population of the cross between 2877S and 2558S present the high degree of sterilit under long day and relatively lower temperature, most of them ar fertile and many have very ligh seed setting rates under short day. Allelism of sterile major-genes of GMS lines derived from Moagken 58S and the methods of breeding appalicable PGMS lines are also discussed in thic paper.