江苏小麦赤霉病防控药剂有效性监测研究分析

Fungicides for Wheat Scab Control in Jiangsu Province: Effectiveness Monitoring Analysis

通过田间试验,评价小麦赤霉病防控药剂的有效性,为植保部门提供药剂选择参考依据。采用‘镇麦12’、‘镇麦9号’为试验品种,以参试杀菌剂的登记最高剂量在小麦扬花期施药2次,最后一次施药25天后调查小麦赤霉病病情及籽粒中DON毒素含量,计算各杀菌剂对赤霉病防效。结果表明,当一个区域内小麦赤霉病菌对多菌灵抗性频率达50%以上时,多菌灵等药剂对赤霉病防效由90%下降到低于80%;当采用含有甲氧基丙烯酸脂类的药剂75%肟菌酯.戊唑醇SC防治赤霉病时,将会刺激DON毒素在小麦籽粒中的积累,毒素含量达到1.405 mg/L,高于对照处理0.598 mg/L。而且,通过有效性监测,初步明确了戊唑醇在本地区小麦赤霉病防治的最低有效用量为120 g/hm^(2)。对防治农药进行有效性监测是小麦赤霉病有效防控的重要保障机制。

Through field experiments, the effectiveness of fungicides for wheat scab control is evaluated to provide reference on fungicide selection for plant protection departments. Taking‘Zhenmai 12’and‘Zhenmai9’as the test varieties, the highest registered dose of the tested fungicides was applied twice at the flowering stage of wheat. The disease index of wheat scab and DON toxin content in grains were investigated 25 days after the last application, and the control effect of each fungicide on scab was calculated. The results showed that when the resistance frequency of wheat scab to carbendazim in an area reached more than 50%, the control effect of carbendazim on wheat scab declined from 90% to less than 80%;while when 75%trifloxystrobin·tebuconazole SC, an agent that contained strobilurin, was adopted to control wheat scab, the accumulation of DON toxin in wheat grains would be stimulated. The toxin content came up to 1.405 mg/L,which was higher than 0.598 mg/L of CK. Moreover, the minimum effective dose of tebuconazole for wheat scab prevention and control in this area was preliminarily determined to be 120 g/hm^(2) by effectiveness monitoring.Monitoring the effectiveness of fungicides is a key safeguard mechanism for the effective prevention and control of wheat scab.