Study on Degenesation of Ovules in the Ovary of Japanese chestnut (Castanea cremata Sieb. et Zucc.)

1.板栗柱头位于花柱顶部，乳白色，周围有表皮细胞包围，细胞壁厚而硬，呈角质层。柱头上附着的花粉在花柱伸长完成时开始萌发。花粉萌发初期授粉时，花粉管伸长较快。每根花柱的花粉管数很少。珠心退化开始于胚珠退化之前，与胚囊发育和受精完成的时间一致，因此认为胚珠退化是由于未受精所致。

1. Stigma of Japanese chestnut located on the top of the style with milk white color, and was surrounded by epidermal cells with thick and hard cell wall like cuticule.2. Pollen adhered on the stigma began to germinate at the stage of completion of style elongation.3. Pollen tube elongated more rapidly when pollinated at the begining stage of pollen germination than the other stage.4. The number of pollen tube per style was very few.5. It was concluded that the degeneration of ovules was owing to nonfertization, because the time of nucellus degeneration which began prior to the ovule degeneration agreed with the time when embryo sac developed and fertilization was accomplished.