核桃生理落果的解剖学观察

核桃生理落果(包括落花)只有1次高峰,高峰期出现在盘花后2周,落果的离层形成部位有2个:一是在结果枝和结果母枝连接处,一是在果实基部。对果实进行解剖研究表明,一部分落果的子房内壁细胞解体、珠被和隔膜组织发育不良,另一部分的解剖结构与正常果无差异。根据离层形成部位和果实败育程度将核桃的生理落果分为前期落果、中期落果和后期落果,初步分析造成前两期落果的主要原因是由于春季雌花分化不完全,从而导致雌花和幼果的败育。

Anatomical Observation on Early Physiological Drop of Walnut Fruit

Based on the investigation in the field,the authors found thatthere was only one peak of physiological drop during the fruit growingperiod which appeared about 2 weeks after full bloom.There were twokinds of abseission layer formation of drops.One was between the bearingbranch and mother bearing branch,and the other one was at the end of thefruit.The anatomic study on fruits indicated that cell and tissue necrosiswere evident in the inner overy wall,integument,and throughout theplacental evaginations in part of the drops,while,for the other drops,there were no differences as compared with normal fruits.The drops ofwalnut can be divided into three kinds,namely,the early,the middle andthe late based on the situation of abscision layer and the degree of tissuenecrosis.The reason that caused the early and the middle drop was theincomplete pistillate flower differentiation last spring.