摘要
用压片法对八倍体小偃麦与硬粒小麦及其杂种F_1小孢子发生和花粉发育进行了详细的细胞学观察。结果表明,两亲本八倍体小偃麦和硬粒小麦的小孢子发生和花粉发育是基本正常的,二者结实率也基本正常。[八倍体小偃麦×硬粒小麦]F_1小孢子发生过程非常紊乱,花粉母细胞减数分裂中期Ⅰ出现较高频率的单价体和多价体,其相对紊乱系数高达0.67;减数分裂晚后期,每个细胞落后染色体平均3.56条;四分体期,每个四分体微核数平均2.82个。在杂种F_1花粉发育的每个时期都可产生不同频率的败育花粉。在三细胞成熟花粉期,杂种F_1可育花粉百分率为67.36%,基本能够满足传粉受精的需要,但其结实率仅为2.79%,远远低于两亲本结实率。因此杂种F_1花粉的败育不是导致其结实率低的主导因素。
The microsporogenesis and the pollen development of two parents, Agrotriticum and T. turgidum, and their hybrid were observed cytologically with squash method in this study. The results show: The microsporogenesis and pollen development of two parents, Agrotriticum and T. turgidum, was normal basically, their seed fertilities were normal basi- cally. The microsporogenesis of hybrid of Agrotriticum × T.turgidum was quite chaotic. The high frequency of univalents and multivalents at meiotic Ⅶ (netphase Ⅰ) of PMC (pollen mother cell) occured frequenty, its relative chabile coefficient reached 0.67. The laggards at meiotic AI (anaphase Ⅰ) were 3.56 per cell on an average. The numbers of micronucleoli in tetrad were 2.82 per tetrad on an average. The abortion of pollen of hybrid occured at every stage of pollen development in different fre quency. The fertile rate of pollens of hybrid was 67.36% at 3-nucleated stage. The numbers of normal pollen were enough for fertilization but the seed fertilities of F_1 was only 2.79%, much lower than that of their two parents. The sterility of hybrid was not mainly owe to the abortion of pollen.
出处
《西北植物学报》
CAS
CSCD
北大核心
1992年第2期87-93,共7页
Acta Botanica Boreali-Occidentalia Sinica
关键词
小偃麦
小麦
小孢子发生
花粉发育
octoploid Agrotriticum,T.turgidum,microsporogenosis, pollen development.
