广西香蕉枯萎病4号生理小种发生情况及香蕉品种抗性鉴定

【目的】明确香蕉枯萎病4号生理小种在广西的发生实况和广西现有香蕉品种对香蕉枯萎病4号生理小种的抗性水平，为制定相应的防控措施提供参考。【方法】在广西香蕉产区随机选择23个村，每村抽取2～3个点，调查香蕉枯萎病4号生理小种的发生情况。用伤根接种法测定11个香蕉品种对香蕉枯萎病4号生理小种的抗性水平。【结果】南宁市西乡塘区、隆安县、钦州市、武鸣县和龙州县均发现香蕉枯萎病4号生理小种发生为害，大多数发病地块的病株率在1．00%-14．00％，病情指数在0．50～10．00，田东县调查点没有发现香蕉枯萎病4号生理小种为害。11个香蕉品种除金粉1号病情指数为50．00，为感病品种（s）外，其他品种病情指数在70．00～100．00，为高感品种（HS）。【结论】香蕉枯萎病4号生理小种已在广西部分产蕉区零星发生，正处于病原菌菌量累积阶段；目前广西栽种的香蕉品种均为感病或高感品种，抵御能力差，需加强对香蕉枯萎病的防控力度。

Occurrence of Fusarium oxysporum Lsp.cubense tropical race 4 and resistance identification of banana varieties in Guangxi

Objective]Occurrence status of Fusariurn oxysporum f.sp. cubense tropical race 4 in Guangxi was surveyed and the resistance of banana varieties cultivated in Guangxi against Fusarium oxysporum f.sp. cubense tropical race 4 was also studied to provide references for formulating the corresponding prevention and control measures. Method]The condition of Fusariurn oxysporum f.sp. cubense tropical race 4 infecting the banana was investigated in 2-3 spots of 23 villages randomly chosen from Guangxi was. Furthermore, the resistance of eleven banana varieties cultivated against Fusariurn oxysporurn f.sp. cubense tropical race 4 was determined using injury root inoculation method. Result]Fusadum oxysporurn f.sp. cubense trop- ical race 4 was found in Qinzhou City, Wuming County, Longan County, Longzhou County, and Xixiangtang District, in which the diseased plant rates were 1.00%-14.00%. All of the eleven banana varieties were highly sensitive （disease index： 70.00- 100.00） to Fusariurn oxysporurn f.sp. cubense tropical race 4 except Jinfen 1 which was sensitive （disease index： 50.00）. Fusari- urn oxysporurn f.sp. cubense tropical race 4 was not present in the investigation spots of Tiandong County. Conclusion ]Fusad- urn oxysporurn f.sp. cubense tropical race 4 was found sporadical in a part banana production area of Guangxi and propagated rapidly. Since banana varieties cultivated in Guangxi were highly sensitive or sensitive to Fusadum oxysporum f.sp. cubense tropical race 4, their disease-resistant ability was poor. More efforts should be made to prevent and control Fusarium oxysporum f.sp. cubense tropical race 4.