Xiangguo Li

Development of a System for Controlling Ginseng Alternaria Leaf Blight (Alternaria panax) to Reduce Fungicide Application and Use

To reduce the amount of chemical fungicides and the number of spray for the control of Alternaria blight of ginseng, biofungicides were used in order to reduce the residue and ensure the safety of ginseng plants. The control efficiencies were 68.34%73.56% against Alternaria blight in 2 times alternate spray of biofungicides and chemical fungicide at 14 days interval whereas the control efficiencies were 87.00%89.42% in 2 times alternate spray of 3 different kinds of chemical fungicides at 14 days interval. In case of treatment combination the control efficiencies were 74.53%87.23% in alternate spray of mixture of biofungicides and chemical fungicides at 28 days interval in all combinations except 2 kinds of combinations (Com-12 and Com-17). Therefore, the alternate application of the biofungicides and chemical fungicides or alternate application of mixture of biofungicides and chemical fungicides could reduce the amount of chemical fungicide about 75.00%83.33%.

Control of Alternaria Leaf Blight of Ginseng by Microbial Agent and Fungicides

The single application of Bacillus subtilis QST713(BS QST713) mixed application with fungicides and alternate application were treated to examine the control of alternaria leaf blight of Panax ginseng. Control value of alternaria leaf blight by single application of BS QST713 at 10 days interval was 83.3%, and those of single application at 10 days interval was by azoxystrobin, chlorothalonil copper sulfate basic, copper sulfate basic, kresoxim-methyl, difenoconazole, mancozeb. When mixture of BS QST713 and fungicides were applied at 14 days interval, the control value of alternaria leaf blight were 83.6% by BS QST713 and mancozeb, and 82.6% by BS QST713 and azoxystrobin. However, mixture of BS QST713 with difenoconazole, kresoxim-methyl, copper sulfate basic and chlorothalonil copper sulfate basic exhibited the disease control values from 61.1% to 76.4%, which showed slightly lower control efficacy. In Daejeon, the alternate application of BS QST713 followed by copper sulfate basic with 14 days interval was 85.9% in control value, which showed the best control efficacy. The alternate application with other tested fungicides slightly decreased to in control value. However, the alternate application of BS QST713 followed by fungicides showed very high control efficacy, which were approximately 90% in Muju, Jeonbuk Province. Consequently, the single, mixed or alternate application of BS QST713 and fungicides could be recommended as a control method to reduce the amount of fungicides.