辐照小麦雌雄配子克服远缘杂交不亲和性的研究

用六倍体小黑麦“黑杂266”作母本,3个春小麦品种“龙辐30138”、“龙麦11号”、“龙辐10271”为父本进行远缘杂交,杂交前用~(60)Coγ射线600—1600rad活体慢照射雄配子或雌配子。通过对受精过程的切片观察,授粉后6小时,辐照雄配子的有61.70％的胚囊解体,辐照雌配子的为70.00％,未经辐照的为59.38％。辐照处理明显提高了杂种的结实率,但是,结实率随剂量的增加而下降。试验表明,辐照雌配子和雄配子的适宜剂量分别为600rad和800rad,但不同品种间辐射敏感性有很大差别。辐照对杂种籽粒的完好率有明显提高。应用组织培养技术进行胚挽救,可使有胚无胚乳杂种种子获得幼苗。

STUDIES ON OVERCOMING INCOMPATIBILITY OF DISTANT HYBRIDIZATION BY GAMMA RAYS

Distant hybridization was carried out after megagametes of hexaploid triticale"Heizha 266"and androgametes of wheat varieties"Longfu 30138","Longmai 11" and "Longfu 10271" were irradiated with 60Co gamma rays from 600 to 1600rad.Through the observation of the pollination,in cut sections,it was found that 60-70 percent of embryo.sacs were disinte-grated 6 hours after pollination.The results of the investigations,showed that the rate of fertilization was significantly increased by the irradiation However,it was decreased with the incr.ease in the dose of the irradiation.The radio-sensitivity of different.wheat varieties varies greatly.The optimum dose of the irradiation was 600rad for megagametes,and 800rad for androgametes.The rate of survival for hybrid seeds,was obviously increased,by the treatment of the irradiation.By using tissue culture,some plants could be obtained from hybrids with.embryo only.