陆地棉、亚洲棉与比克氏棉杂种F1及回交后代的育性研究

三元杂种 (亚洲棉×比克氏棉 )×陆地棉 ]及其反交的回交后代在性状上发生疯狂分离 ,在育性上分离出 3种类型 :可育型、不完全可育型、不育型。对这 3种类型及三元杂种F1减数分裂及其花粉的形成过程观察表明 ,三元杂种F1及回交后代的不育型 ,不育的根本原因在于减数分裂中期染色体不能正常配对 ,引起部分染色体滞后及染色体不均等分配 ,从而产生多分孢子和微核 ,最终导致不育花粉的产生 ;不完全可育型 ,大部分染色体联合配对成二价体 ,仅个别为单价体 ,这些单价体在后期随机向两极分离 ,产生的二分孢子有的正常 ,有的不正常 ,进而形成的花粉粒仅个别正常 ;可育株染色体配对正常 ,因而形成的花粉粒可育

Studies on the Fertility of F1 and Backcross Progenies from (Gossypium hirsurtum×(G.arboreum×G.bickii))

Backcros s progenies BC4F1 of interspecific hybrid(G.hirsutum×(G.arboreum×G.bickii)) seperated crazily in every charac ters and many new characters appeared.According to the fertility,the plants of b ackcross progenies were classified into 3 groups:sterile, semisterile and ferti le plant and chromosome behavior during meiosis in pollen mother cell of the in t erspecific hybrid F1 and the three types were studied.The main results are as follows:the sterile cause of F1,BC4F1 sterile material in the trispecific hybrid was that the chromosomes could not make a pair normally in meiosis, leadi ng to some lagging, uneven distributing chromosomes, multispores, micronuclei and sterile pollens. In semisterile plants, the chromosomes could make a pair mostly in meiosis, only a few could not make a pair normally.In fertile plants of BC4F1, the chromosomes could make a pair normally in meiosis and normal pollen grains were formed, the fertility was recorved.