Abstract
Effect of a new systemic bactericide, techlofthalam [N-(2, 3-dichlorophenyl)-3, 4, 5, 6-tetrachlorophthalamic acid], against bacterial leaf blight of rice plants was evaluated by means of several test methods in the greenhouse. Techlofthalam showed no activity against Xanthomonas oryzae, the causal bacterium in vitro when estimated with a turbidimetric method. Soil application of techlofthalam at the dosages of 0.3 and 0.6g/m2 showed considerable effectiveness for inhibiting lesion formation and development, though the effect somewhat delayed after application. It was elucidated by the experiments relating to foliage application that the agent had poor preventive and curative action for control of lesion formation in the inoculated leaves, and that it gave an excellent control effect against lesion development with a spray inoculation method though it was fairly poor with a needle prick method. Techlofthalam showed no plant physiological activity to any of plants tested by means of foliage application and pre-emergence soil drench.
