三系水稻保持系航天育种的研究

Study on Space Breeding of Maintainer Line of Three Lines Rice

[目的]研究三系水稻保持系航天诱变突变株的育性变化情况。[方法]以籼型水稻单株纯系品种特B、湛B、双青B和II-32B的种子为材料,各品种取1/2种子进行航天诱变,余下1/2种子为对照,研究航天诱变突变株测交和回交后代的性状表现及遗传变异。[结果]4个保持系突变株测交后代可育花粉率变幅为0-25.6%,回交一代可育花粉率变幅为0-72.2%。各突变株测交后代自交结实率变幅为0-8.2%,突变株对不育系的不育性保持能力表现出一定的下降趋势;回交后代自交结实率与对照差异显著,II-32A×II-32B3-1的后代自交结实率最高,为33.4%。回交后代农艺性状与对照的差异比上一代更明显。[结论]三系水稻保持系航天诱变突变株回交后代的育性有较大变化。

[Objective] The study aimed to research the fertility change of mutants of maintainer line of three lines rice by space mutation.[Method] With the seeds of 4 individual pure line varieties of indica rice including Te B,Zhan B,Shuangqing B and II-32B as materials,1/2 seeds of each variety were taken for space mutation and the other 1/2 seeds were taken as CK.The characters and genetic variation of testcross and backcross progeny of mutants by space mutation were studied.[Result] The pollen fertility rate of testcross progeny of mutants of 4 maintainer lines was 0-25.6% and the pollen fertilities rate of BC1 was 0-72.2%.The self-fruitful rate of testcross progeny of each mutant was 0-8.2%.The holding capacity of mutants on sterility of sterile line showed a certain downward trend.The self-fruitful rate of backcross progeny had significant difference with that of CK and the self-fruitful rate of progeny of II-32A×II-32B3-1 was the highest,being 33.4%.The difference of agronomy character between backcross progeny and CK was more obvious than that of the last generation.[Conclusion] The fertility of backcross progeny of mutants of maintainer line of three lines rice by space mutation had bigger change.