荸荠枯萎病发生动态及防治技术

荸荠枯萎病在我国各个荸荠Eleocharis dulcis产区普遍发生,是影响荸荠产量的重要病害。为有效防治该病害,于2010—2012年调查了湖北省荸荠枯萎病的田间发生动态,并进行了荸荠品种抗病性评价、室内药剂筛选及药剂处理球茎盆栽和田间试验。3年田间病情调查结果表明,荸荠枯萎病于8月中旬开始发生,8下旬—9月上旬温度适宜,病害开始缓慢增长;9月下旬—10月中旬为该病发生的高峰期;病情指数均与温度呈显著负相关,但各年份的病情指数与相对湿度和降雨量均无显著相关性。沙洋荠、肇庆荠、韶关马坝荠、桂林荠-1品种对荸荠枯萎病有较强的抗性。10%苯醚甲环唑、25%多菌灵、40%氟硅唑和25%嘧菌酯4种药剂处理球茎均有利于荸荠出苗。经多菌灵和氟硅唑处理的球茎假植到大田2个月后对荸荠枯萎病仍有一定的防治效果,防治效果分别为22.3%和27.0%,而嘧菌酯和苯醚甲环唑对该病基本无防治效果。

Occurrence and control of Fusarium wilt of Chinese water chestnut

Fusarium wilt of Chinese water chestnut, Eleocharis dulcis, is wildly distributed throughout E. dulcis producing areas, and it is one of the most important diseases, which has become a major limiting factor for E. dulcis production. In order to control Fusarium wilt of Chinese water chestnut, the disease occurrence from 2010 to 2012 growing seasons, evaluation of E. dulcis cultivars resistance, comparison of the inhibition of different fungicides, and pot and field trials of corm fungicide treatments were studied. The results showed that symptoms of the disease were initially occurred in the middle August. Because of the appropriate temperature, late August to early September was suitable for the disease, and it began to grow slowly. Late September to middle October was the peak stage of the disease. The disease index of the three years was significantly negative correlated with temperature, but has no significant correlation with relative humidity and rainfall. Shayangqi, Zhaoqingqi, Shaoguanmabaqi and Guilinqi-1 had a relative strong resistance to Fusarium wilt in two year field trials. The four fungicides, 10% difenoconazole, 25% carbendazim, 40% flusilazole and 25% azoxystrobin, were benefit for E. dulcis corms to germinate. Two months after provisional planting, corms treated by carbendazim and flusilazole still had control efficiency of 22.3% and 27.0%, respectively, however, both azoxystrobin and difenoconazole had no control efficiency to this disease.