Study on the Self fertilization of the Tea Plant

Abstract

In the performance of seed-propagation, it is desirable that the percentage of self-fruiting is high. This percentage varied from 0.2 to 4.2%, and the avera e was 2.2% for the last five years, so it was assumed that the tea plant is almost self-unfruitfulness. In order to study the cause of this phenomenon, the authors attempted to investigate the mechanism of self-fertilization and try to find the artificial method effective to get self-fertilized seeds.
From the studies of the behaviour of the fruit drops and the growth rate of embryo sac, it was cleared that the rate of fruit drops was remarkably different, between self and cross pollinated flowers and the droppings of the self pollinated fruits were mainly due to the non-fertilization.
The cause of low self-fruiting was thought to be due to the low degree of self-compatibility. This mechanism was presumed as follows. Although the development of pollen tubes in style was slow as well as the percentage of pollen germination on stigma, main cause was the remarkable retardation of bollen tubes at the tissues between the base of style and the upper part of ovary.
With the aim of artificially promoting the self-fertilization, we tried the bud pollination, the old flower pollination, the spraying of 10^-4% Fruitone solution and the pollination at the close of flowering time. In the case of the former three methods, the development of pollen tubes in style was promoted as well as the germination in stigma, but this promotion could not yet surpass the retardation of tube growth between the base of style and the upper part of ovary, so the effect of these treatments on fertilization was not marked.