STUDIES ON JUNE DROP AND ASSIMILATE TRANSLOCATION IN KAKI (Diospyros kaki L.f.)

果实位置和裸芽3花组合对山核桃无籽落子或孤雌果核的影响。为阐明孤雌结实与果实间同化物竞争的关系，对扶玉和平兰仁进行了研究。1. 授粉花和未授粉花的果座在同一枝的上部最高，基部最低。2. 所有授粉的枝条上部的单性果实。3. 在花授粉和不授粉的同一茎上，种子多的果实比单性果的结实率高。4. 单性果在不授粉的所有花的茎部，尤其是在上部，茎部长度递减。5. 无籽果实的生长在不同的果位之间存在显著差异，许多较小的果实倾向于脱落。6. 单性结实的坐果在果实位置和单梢有花果的情况上存在差异，而且‘扶玉’和‘平田仁’的单性结实的变异模式非常相似。结果表明：1)“扶玉”单性结实的显性因素比遗传因素更明显；2)“扶玉”和“平田仁”单性结实的遗传特征差异不显著；3)无籽果实的落子是由果实间的竞争引起的，而单性结实的坐果是由竞争果实间的相对下沉强度优势造成的。

Influence of fruit position and the combination of 3 flowers with or without pollination in a baring shoot on seedless fruit drop or parthenocarpic fruit set of kaki (Diospyros kaki L.f.) cvs. Fuyu and Hiralanenashi was investigated to clarify the relation between parthenocarpy and competition for assimitates among fruits. 1. Fruit set of pollinated and non-pollinated flowers was the highest at upper position and lowest at basal one in a shoot. 2. Parthenocarpic fruit of upper position in the shoot of all pollinated. 3. More seeded fruits had a tendency to set higher than parthenocarpic fruits in the same shoot with flowers pollinates and non-pollinated. 4. Parthenocarpic fruit set in the shoot of all flowers non-pollinates, especially at the upper position, decreasing length of shoot. 5. These was significant difference in seedless fruit growth among the fruit positions, and many of the smaller fruits tended to abscise. 6. Parthenocarpic fruit set varied in fruit position and presence of pollinated fruit in a shoot, and the variation patterns of parthenocarpy were very similar in 'Fuyu' and 'Hiratanenashi'. We concluded that 1) a dominant factor of parthenocarpy in 'Fuyu' was more evidential than hereditary, 2) these was no remarkable difference in hereditary characteristic of parthenocarpy between 'Fuyu' and 'Hiratanenashi' and 3) fruit drop of seedless fruit was induced by the competition among fruit, and the parthenocarpic fruit set was resulting from relative advantage in sink strength among competed fruits.