Histological Observation on the Effect of Unilateral Gravitational Pull on the Growth in Thickness of Abelmoschus gultino-textilis Kagawa and its Parents, A. esculentus Moench and A. Manihot Medic.

The seedlings of gultinous hemp and its both parents, Tororo-Aoi and okra, were horizontally kept with their main axes for some time, and the histological comparison was made with one another as well as with those vertically kept for the same periods. The development of tissues, especially the enlargement of cambial cells is most remarkable in glutinous hemp. A general view of xylem is fairly different from one another as the result of the fact that'a state of lignification among them is somewhat different, though in all of them the xylem is composed of two kinds of portions, that is, the one made up of lignified cells and the other unlignified ones, alternately arranged , showing an appearance of concentric circle. Thus, glutinous hemp surpasses the others in enlargement of cells, thickening of cell walls and progress of lignification. The hypocotyls horizontally kept attain a remarkable growth in all three kinds of plants, compared with those of controls, and at the same time, they show an epitrophic growth. Thus, a striking difference is brought about in a structure of phloem fibrous tissue and xylem between both upper and lower sides in particular. From a viewpoint of the shape and arrangement of cells, thickness of walls and degree of lignification, it may be safe to say that glutinous hemp closely resembles Tororo-Aoi