三唑酮防治小麦条锈病的持效期研究

Studies on the Duration of Effectiveness of Triadimefon Against stripe Rust of Wheat

三唑酮防治小麦条锈病的持效期很长。幼苗第1叶喷施有效成分浓度400μg/mL以上的药液,持效期55d以上,可有效地保护第2叶至第6叶或更高叶位的叶片;喷施200μg/mL药液可保护前4个叶片,持效期34d上;100μg/mL三唑酮对第2叶有较好的保护作用;成株期喷药,用药浓度100μg/mL以上,持效期56d以上。为保证和提高防治效果,必须把握喷药时机,适期早喷。

The duration of effectiveness of Triadimefon against wheat stripe rust was evaluated in seedling and adult tests. When the primary leaves of seedling were treated with 400-600 ng/mL suspension of Triadimefon, the effective duration was longer than 55 days and more than 6 leaves was fully prothcted. The 1st to 4th leaves were free from stripe rust after spraying 20.0 ug/mL suspension on the primary leaves. Only the 1st and 2nd leaves were effectively protected by application of 100 ng/mL suspension. In the field experiment, 100 ug/mL suspension of Triadimefon was sprayed on upper leaves of adult plants, then the duration of effectiveness was longer than 56 days. It was stressed that earlier application of Triadimefon in the season was very important to get successful control of wheat stripe rust.