An experiment on integrated control of root-rot of tung-oil trees

Root-rot of tung-oil tree caused by Fusarium solani f. sp. aleuritidis Chen et Xiao, is a new and serious root disease in Sichuan. According to the climate-ecological feature of the main tung-oil tree production areas in Sichuan, the disease development zones were divided into 3 parts, i. e. Seriously-infected, generally-infected and noninfected areas. Based on the soil-ecological feature, the different stand condition of disease dovelopment may be grouped into the following 4 series:1) the seriously-damaged tung-oil stand (pH 7.3~8.3), 2) moderately-damaged tungoil stand (pH 6.5~7.3), 3) lightly-damaged tung-oil stand (pH 6~7) and 4) nonifected tung-oil stand (pH 5~6). In the seriously-damaged tung-oil tree stand, the large scale trials with planting resistance trees in combination with fungicidal treatment showed that silviculture-ecological control had a good effect. In the stands of the 2nd and 3rd groups, the disease can be effectively prevented by planting resistant trees.