Breeding of the Large Panicle and Good Quality Indica CMS Line Zhe 91 A

Zhe 91A is a new WA-type indica CMS line developed from crossing V20A with the selected plants from the F_3 lines of Zhenong 8010B/Zhenong 91 and backcrossing successively the complete male sterile plants whose pollen sterility is strictly checked under microscope with their corresponding paternal plants. It has a complete male sterility with 100% of sterile plants and 100% of pollen sterility. It has large panicles (155.6 spikelets/panicle, 54.4 spikelets/panicle more than the check Xieqingzao A). Most of its grain quality characters such as chalky rice, gel consistency and amylose content are better than those of Xieqingzao A, a CMS line most popular in Zhejiang Province. It is easy to conduct hybrid seed production because of its high outcrossing rate (55.7%) with a high stigma exsertion rate (60.1%). Zhe 91A was technically identified in Zhejiang Province in September,2003. Some promising hybrids derived from Zhe 91A are being tested in trials.