芒果无仁和小仁果实产生机理研究

STUDY ON THE MECHANISM OF SEEDLESSNESS IN MANGO

通过去雄套袋、花粉生活力及萌发率测定，花粉母细胞减数分裂期染色体行为观察，胚珠、胚囊及种胚的解剖观察，研究了东镇红芒无仁或小仁果实产生的原因。结果表明：（１）雄蕊发育正常：花粉母细胞减数分裂染色体数目和行为以及花粉生活力和萌发率均属正常。（２）东镇红芒无自动单性结果特性，授粉刺激是其座果所必需的。（３）雌蕊败育是东镇红芒产生无仁或小仁果的主要原因。雌蕊败育表现多样化，如早期的胚珠萎缩、胚囊败育或种胚发育过程中途败育，但主要是发生于八核时期的卵细胞、极核、助细胞和反足细胞在同一胚囊或不同胚囊的退化。

? In order to find out the mechanism of seedlessness in mango (M indica L cv Dongzhen Hongmang), pollen viability and germination rate, development of embryo sac and behaviour of chromosomes in pollen mother cells were studied Emasculation test was conductedThe results were as follows:(1) Behavior of chromosomes in pollen mother cells were normal and no significant difference of pollen viability and germination rate between the early and late flowers were observed (2) Pollination was essential for fruit-set in mango (3) Degeneration of egg、 synergids、 polar nuclei and antipodals in one or different ovules, the shrinkage of ovule cells at early stage and the disintegration of embryo after anthesis resulted in seedlessness