氰烯·戊唑醇不同用药时间和次数对小麦赤霉病及DON毒素的管控效果

扬花初期是防控小麦赤霉病的最佳时期,为了探索错过扬花初期用药补防对小麦赤霉病和毒素的管控效果,本试验选择姜堰地区存在的13个小麦品种,用48%氰烯·戊唑醇SC进行赤霉病防控,通过扬花初期漏防6天后补防1次和扬花初期用药1次、扬花初期用药2次3种方式,对各品种小麦赤霉病防效和DON毒素控减效果进行比较。结果表明：错过扬花初期6天后用48%氰烯·戊唑醇补防1次,对各品种赤霉病的平均病穗率和病指防效、DON毒素控减效果比扬花初期防治1次分别低15.87%、21.25%、35.48%,比扬花初期用药2次分别低39.79%、44.87%、66.84%。赤霉病最适首次防治时间是扬花初期,扬花初期漏防6天后补防1次,对赤霉病和DON毒素的管控效果较差,坚持扬花初期+6天后两次用药效果最好,在各个品种中该趋势表现一致。

Efficacy of Cyanene·pentazolol Application Methods on Controlling Wheat Scab and DON Toxin

The best period to prevent and control wheat scab is on the preliminary stage of flowering. To explore the control efficacy on wheat scab and toxins when missing the preliminary stage of flowering, 13 wheat varieties in Jiangyan were selected for this experiment, and 48% cyanene·pentazolol SC was used to control the wheat scab. We designed three application methods: spraying 48% cyanene·pentazolol SC once after 6 days missing the preliminary stage of flowering, spraying 48% cyanene·pentazolol SC once at the preliminary stage of flowering, and spraying 48% cyanene·pentazolol SC once at the preliminary stage of flowering plus once after 6 days. The controlling efficacy of the 3 treatments against wheat scab, as well as their impact on the content of DON toxin in wheat grain were compared for each wheat variety. The results showed that the average control efficacy on diseased ear rate and the disease index and the reduction effect on DON toxin under spraying 48% cyanene·pentazolol SC once after 6 days missing the preliminary stage of flowering were 15.87%, 21.25% and 35.48% lower than those under spraying once at the preliminary stage of flowering respectively, and were 39.79%, 44.87% and 66.84% lower than those under spraying once at the preliminary stage of flowering plus once after 6 days. Therefore, the optimal first control time for scab is at the preliminary stage of flowering, while spraying 48% cyanene·pentazolol SC once after 6 days missing the preliminary stage of flowering has relatively poor control efficacy on scab and DON toxin. Spraying 48% cyanene·pentazolol SC once at the preliminary stage of flowering plus once after 6 days shows the best efficacy, and the performance trend of all the varieties are consistent.