MCPB-ethyl疏花对富士苹果授粉受精及胚珠发育的影响

Effect of MCPB-ethyl on the Pollination,Fertilization and Ovule Develop ment of Fuji Apples

通过在花期用MCPB-ethyl处理,对富士苹果花粉的发芽、花粉管的伸长以及胚珠的发育等进行了形态方面的观察和探讨,以阐明MCPB-ethyl的疏花机制。结果表明,MCPB-ethyl对花粉的发芽及花粉管的伸长没有影响,整个受精过程与对照相同,没有发现异常。但受精后胚乳核只进行了数次分裂便停止生长,此后珠皮、珠心细胞迅速解体。根据以上结果,认为MCPB-ethyl的疏花效果不是通过影响花粉的发芽或花粉管的伸长阻碍受精所致,而是使胚和胚珠的发育停止,形成离层导致了落花。

The aim of this study is to clarify the thinning mechanism of the apple thinner MCPB-ethyl which was sprayed at blossom stage of Fuji variety,the effects on pollen germination,pollen-tube growth and ovule development were observed.Results showed no effects on the pollen germination and pollen-tube growth were noted,but it was discovered that after fertil-ization development of the endosperm nucleus stopped after only a few reduction division proceeded,the cells of nucellus and integument disintegrated quickly.It is considered that the action of MCPB-ethyl on thinning is not due to impediment of pollen germination and pollen-tube growth;possibly it is because of the retardation of ovule development stopped,which re-sults in flower abscission.