高频率无融合生殖水稻的研究

THE STUDY OF HIGH FREQUENCY OF APOMICTIC RICE MATERIAL(HDAR)

籼粳杂交后代以及双苗与粳稻杂交后代经特殊方法处理后选育而获得两个高频率无融合生殖水稻材料(HDAR)。它具有的特点是,(1) 不经受精自发形成胚。在开花前或开花后1～2天的胚囊中可发现球形胚、游离的二个极核和反足细胞团。(2) 高的无融合生殖发生频率:HDAR001为48%,HDAR002为50%。(3) 出现无胚乳苗、中间苗、反向苗、侧生苗、小种子苗和瘦长种子苗等多种异常苗。(4) 根尖染色体检查为二倍体;并具有较高的结实率,HDAR001为80%左右,HDAR002为58～85%。因而它不同于国内已发现的具无融合生殖特性的水稻材料,如多胚苗、SAR-1、雄性不育单性结实和胚乳培养植株单性结实材料。它对固定水稻杂种优势和水稻育种具有独特的意义。

A new rice material with high frequency of apomixis(HDAR)was reported in this paper.This material has the ollowing characteristics:(1) It was derived from a crosstreated with a special method.(2) Embryo was formed utonomously in the unfertilized ovules.Globular embryo,two polar nuclei and antipodal cell mass could be observed n the embryo sacduring 1 to 2 days before and after anthesis.(3) They showedhigh frequency of apomixis:HDAR 001 as 48%,HDAR 002 was 50%.(4) Various abnormal seedlings were obtained e.g.seedlings from seeds without ndosperm,those germinated form some where in the middle ofseeds,seedlings germinated from opposite end of eeds,those from latteral side of the seeds,thosefrom small seeds,and those from thin and long seed.(5) Their hromosome number of root tipwas diploid,2n=2x=24. Moreover,they showed normal seed setting rate:HDAR 001 was80% and HDAR 002 ranged from 58% to 85%.In comparison with other apomictic ricematerials,such as olyembryonic rice,SAR-1,parthenogenesis material direved from malesterile line and plant from endosperm ulture,HDAR is a new superior apomictic rice material.