八倍体小偃麦与普通小麦自交后代的细胞遗传学研究

CYTOGENETICS OF SELFING OFFSPRINGS BETWEEN OCTOPLOID AGROTRITICUM AND T.AESTIVUM L.

本研究以八倍体小偃麦—小偃7430和普通小麦品种—鲁麦1号为亲本,对其杂种的三个自交世代(F_1、F_2、F_3)的细胞遗传学进行了研究。从对小偃7430与鲁麦1号自交后代植株花粉母细胞减数分裂中染色体行为的分析表明,从杂种F_1开始,随自交世代的增进,杂种后代植株染色体数逐渐减少,植株染色体数越多,减数分裂中期I单价体出现频数,多价体出现类型及频数也越多,但二价体出现的个数基本稳定在21个左右。另外,从染色体数目较多的杂种F_2代植株中选出了一株二体异附加材料;从F_3代植株中选出了一株花粉母细胞减数分裂中期I染色体构型基本稳定为21个二价体的普通小麦材料,初步实现了将偃麦草的某些特异染色体或基因导入普通小麦遗传背景的目的。

Octoploid Agrotriticum Xiaoyan 7430 and common wheat cultivar Lumai 1 were used as parents to study the cytogenetics of their 3 selfed generations (F_1, F_2 and F_3). The meiotic behavior of PMC in selfed offsprings between Xiaoyan 7430 and Lumai 1 showed that chromosome numbers in the selfed progenies decreased gradually as selfing progressed from the hybrid F_1 to F_3. The frequency of univalents and both frequency and types of multivalents at MI increased gradually as chromosome numbers of the hybrid plants increasing. However, the number of bivalents was basically 21 or so. In addition, one alien additional line of disomics was created from hybrid F_2 which had more chromosome numbers, and an individual plant with 42 chromosomes or 21 bivalents at MI was also selected. The special chromosome(s) or superior gene(s) from Agropyron has got to be preliminarily transferred to the genome of common wheat.