Studies on the Root Development in Tea Plants :A preliminary report

[摘要] The author investigated the development of root system and its seasonal change in severa1 varieties of tea plant. The root system were studied by Weaver's trench method (a direct mcthod). The soil of the tea garden used was alluvial clayey loam, the top soil being of redbrown color and 105cm. in depth, and the subsoil containing a number of large gravels. The surface soil, in which most roots distribute, was about 30cm. deep. The seedling plants of five years old have usually much deeper and more vigorous root systems compared with plants of the same age propagated by layering. But as the plants grow older the roots are inclined to seem to develop more and more in adaptation to the soil conditions, and the difference in root system between the seedage plants and the clonal plants becomes smaller. In plants of twelve years old, however, the seedling plants have still deeper and wider root system than the cutting plants. The form o the root systm varied according to the varieties. Among the tree o twelve years old, the roots penetrated deeply into the subsoil in some varieties, while in the others it did not reached the subsoil. The form of the root system, also, was found closely related with the top form of the plant. The top of erect form had deep root system, while the plant o= dwarf form showed shallower root system. The plant of round form have intermediate root system. The seasonal change of the weight of roots in young plants varied according to the variety, the method of propagation, and the age of plant. But generally the root weight increase, remarkably from March to October. During winter the weight did not increase, though the root continued to grow to some extent. The value of T-R ratio was, as a rule, high in August and September. As the plants grow older, the ratio seemed to decline gradually. The quantity of new and fibrous roots was especially large in April and August or September. This fact may suggest a suitable period of transplanting of the plant.

[学科分类] 农业科学（综合）