Abstract
Varietal difference in the growth habit of the adventitious roots of five white clover varieties, Oregon Ladino, Witte Cultuurklaver C.B., Welsh S-100, Kersey and Wilkla Witte Weideklaver was compared in relation to the denudation of the stand in the field after disappearance of the tap root system. In the seedling experiment, growth of the root was related to that of the top by means of the allometric formula, log Y=log b+K log X in which Y and X represent the weight of root and top respectively, b and K being constants. It was found that Wilkla showed more growth on the top rather than on the root, resulting in a decrease of regression coefficient, K. In the field experiment, the mean length of the internode positioned around the plant base was shortened in the following order ; Wilkla, Kersey, S-100, Ladino and Witte. Mean weight of adventitious root of each variety was 11.59mg in Ladino, 12.31mg in Witte, 15, 94mg in S-100, 15.06mg in Kersey and 7.40mg in Wilkla. Denuded area of the tops around the plant which tap root was removed artificially was produced more markedly in Wilkla and Kersey. From these resulrs, when the tap root system is lacking, the ability of nodal root to compensate the role of it seems to be higher in the variety which possesses the shortened internode and the better root growth around the plant base.
