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.