棉属远缘杂种后代根尖细胞有丝分裂的染色体行为研究

A STUDY ON THE CHROMOSOME BEHAVIOUR OF ROOT TIP CELLS IN INTERSPECIFIC HYBRIDS OF GOSSYPIUM DURING MITOSIS

观察了棉属远缘杂种后代根尖细胞有丝分裂的染色体行为。发现在分裂过程中。出现一系列不正常现象,如体细胞中染色体数目的变异;双核及多核仁细胞;前期和中期染色体分离成2～3群,或有1～3个染色体远离染色体群;后期出现落后染色体,或有"桥";末期形成有3～4个核的细胞等。棉属远缘杂种体细胞分裂各个时期不正常细胞的百分率,远远低于其花粉母细胞减数分裂时不正常细胞的百分率。

The chromosome behaviour on root tip cells of interspcific hybrids of Gossypium during mitosis has been studied.Different kinds of anomalous behaviour of chromosomes during mitosis were observed.The chronosome numbers in some of the observed cellswere abnormal and different from each other among them.It was found that stme of the root tip cells had two or more nuclioli.It was also noticed that with some of the mitotic cells at prophase and metaphase their chromosomes separated into 2～3 groups or 1～3 chromosomes departed form the other chromosomes.In some mitotic cells at anaphase a few chromosomes lagged behind the others as the chromosomes moved to the opposite poles.There alse appeared chromosome bridges in some of the mitotic cells at anaphase.The rate of abnormal mitotie cells in interspecitic hybrids of Gossypium is much less than that found at the meiotic division of the hybrids of the same cross combinations.