转基因棉花早代材料细胞学变异研究

Study on Cytological Variation for Early Generation of Transgenic Cotton

农杆菌介导转基因棉花早代 ( T0 )材料 ,花粉母细胞的染色体构型变异很大 ,只有部分二价体 ( 7～ 1 6个 ) ,多数是单价体 ,没有更高的价体。二价体位于赤道面 ,但多形成染色体桥。单价体多散布在两极。减数分裂后形成 1～ 8个分体的多分体 ,其中四分体虽然比例很高 ,多为畸形。染色体数目的减少、PMC染色体构型变异等 。

Chromosome configurations of pollen mother cells (PMCs) in early generation (T 0) of Agrobacterium mediated trangenic cotton vary very much, with a lot of monovalents, a few bivalents but without tri or malt valents. Bivalents situated in equatorial plane but most of them form chromosome bridges. Most monovalents scattered in the two polars. At the tetrad stage, mono to octa cytes (octads) form following the meiotic divisions of PMCs, and among them, tetrads occupied more percentage though most are abnormal in morphology. Chromosome number reduction and the variations of the chromosome configurations may be the direct reasons of highly abortion of these cotton.