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以棉属(Gossypium)的四个栽培种的种间杂种F_1植株为材料,观察花粉母细胞减数分裂的染色体行为和测定花粉萌发率。结果表明:在中期Ⅰ,二元杂种(亚洲棉×草棉)F_1出现一个四体环;(陆地棉×海岛棉)F_1通常联会成26个二价体。三元杂种[(亚洲棉×草棉)F_1×陆地棉]F_1,[(亚洲棉×草棉)F_1双二倍体×陆地棉)F_1和四元杂种[(陆地棉×海岛棉)F_1×(亚洲棉×草棉)F_1双二倍体]F_1分别出现11.7个、8.8个和8.4个单价体以及1.2个,5.6个和5.7个三价体。在后期Ⅰ,两个二元杂种F_1的染色体分离较规则,而三元和四元杂种F_1极不规则。在四分体形成时期,两个二元杂种F_1的异常四分体频率为18.3～20.2％,三元和四元杂种F_1高达71.2～74.7％。各杂种F_1及其亲本花粉萌发率测定表明:(亚洲棉×草棉)F_1花粉的萌发率为54.3％,表现半不育;(陆地棉×海岛棉)F_1为85.7％,与其双亲基本一致;而三元和四元杂种F_1的花粉萌发率极低,仅为7.1～12.4％,表现高度的不育。
The interspecific hybrid F_1 plants from four cultivars of Gossypium were used as materials to observe the chromosome behavior of meiosis of pollen mother cells and to determine pollen germination rate. The results showed that there was a four - body loop in F_1 of binary hybrids (Asiatic cotton xerophytic cotton) in metaphase I, and F 1 (upland cotton × sea island cotton) usually formed 26 bivalent bodies. The results showed that F_1 and [Quercus × Ficus × F. Cotton] F_1 and F4 × F. (Asiatic cotton × cotton plant) F_1 double diploid] F_1 showed 11.7, 8.8 and 8.4 units and 1.2, 5.6 and 5.7 units, respectively. In late stage Ⅰ, chromosome segregation of F_1 was more regular than that of F_1, while F_1 of ternary and quaternary hybrids was extremely irregular. During the tetrad formation, the abnormal tetrad frequencies of the two binary hybrids F_1 ranged from 18.3% to 20.2%, and the F_1 of ternary and quaternary hybrids reached 71.2% to 74.7%. The pollen germination rate of hybrid F1 and its parents showed that the germination percentage of F_1 pollen was 54.3%, showing semi-sterility. The F 1 content of 85% cotton was the same as that of its parents. However, the pollen germination rate of F1 and F3 was very low, only 7.1 ~ 12.4%, showing a high degree of infertility.