Study On The Occurrence Characteristics And Prevention Of Tobacco Black Shank In Sanming Of Fujian Province

Tobacco Black Shank(TBS) caused great harm and occurred with tobacco bacterial wilt, which was difficult to controlling because of lacking resistant variety and soil infection. TBS caused output of 370,000 kg loss and value of 3.36 million yuan loss every year in Sanming, which severely restricted the healthy and sustainable development of tobacco production. Exploring occurrence became one of the basis of controlling the disease with full using of few resistant cultivars.On this background, the paper studied the occurrence characteristics and prevention of TBS in Sanming of Fujian province. Using differential hosts (L8,Nc1071,N.nudicaulis and Xiaohuangjinl 025),the physiological race of P. parasi tica var. nicotianae could be determined base on the symptoms of differential hosts, meanwhile an disease nursery planted Cuibi-1 was set up from 2007～2009, we analysis the epidemic law combining local historical data. According to the race, we did resistance identification of major varieties to TBS by artificial inoculation, and field efficacy was done on controlling TBS. With making full use of forecasting network, IPM demonstration area planted Cuibi-1 was set up.The results indicated that:The epidemic curve of TBS existed S curve every year in Sanming tobacco-growing areas. The disease began to explicit at mid-April, then aggravated gradually, and into disease peak at first ten days of June, furthermore the disease changed to being steady; Physiological race of P. parasi tica var. nicotianae was the race 0 according to the response of identification hosts in Sanming tobacco-growing areas; Among 6 varieties,the resistance of 3 varieties was MR,K326 was the strongest, secondly Yunyan87 and Yunyan85; CB-1 was MS; Yongding-1 and Honghuadajinyuan were susceptible varieties, but Yongding-1 was the weakest. Based on the field efficacy, metominostrobin was 75.08%, propamocarb hydrochloride was 61.45%, fenoxapropethyl was 58.11%, metalaxyl-mancozeb was the poorest, only 48.33%.Because of comprehensive control measures, the yield was 2,175.6kg/hm2 and the average value was 3,9160.8.7yuan/hm2 in the demonstration area, and increased farmers' income, which were significantly higher than those in control group.