番荔枝开花生物学与人工授粉研究

对三年生番荔枝（Ancnona squamosa L.)实生树的开花生物学和人工授粉进行了研究并发现；番荔枝的花有两荔异熟现象，人工授粉能提高座果率，简便而有效的方法是用毛笔直接从树上花药自然裂开的花上聚花粉并立即授在花药没裂开的花上，授粉后两周的座果率达87．9％，授 在花药裂开的花上，座果率为5．3％，与对照照座果率4．4％没有区别，说明花药裂开柱头容受性完全消失，花药裂开时间与品种特有关，目前，广东栽培的番荔枝分为花药早上裂开和傍开两种类型，这两种类型的不同品种之间授粉也能提高座果率，授粉后两周的座果率为83．3％。说明花裂开关12h柱头容受性仍完全正常。

STUDY ON THE BLOSSOM BIOLOGY AND HAND POLLINATION OF THE CUSTARD APPLE (Annona squamosd L. )

The blossom biology and hand pollination on the custard apple seedlings were studied and the following found. I. The flowers of the custard apple are dichogamous. A simple and effective way was to take the pollen directly from flowers in anther dehiscence on the bee with a brush and then transfer it to other flowers without anther dehiscence. The rate of fruit set was 87. 9% in two weeks. However, putting pollen on the floweers in anther dehiscence, the rate of fruit set achieved was 5. 3%with the same level in control 4. 4%. This showed that the sticks lost its receptivity completely during anther dehiscence. 2. The time of anther dehiscence varied with the varieties. The custard apple grown in Guangdong may be divided into two tyoes: morning dehiscent and evening dehiscent. 3. Cross pollination could be carried out between the two tyoes (morning and evening dehiscent) in the above way . The rate of fruit set obtained was 83.3%. It showed that stigma receptivity was still completely effective at 12 hours before anther dehiscence.