El Aalaoui Mohamed, Rammali Said, Bencharki Bouchaib, Sbaghi Mohamed
National Institute of Agricultural Research, Rabat, Morocco.
Faculty of Sciences and Techniques, Lab of Agro-Alimentary and Health, Hassan First Univ of Settat, Settat, Morocco.
Neotrop Entomol. 2024 Dec 6;54(1):2. doi: 10.1007/s13744-024-01215-9.
The sugar beet flea beetle, Cassida vittata Vill. (Coleoptera: Chrysomelidae), is a major pest in Morocco's sugar beet crops and is primarily controlled with chemical insecticides despite environmental concerns. Our aim was to assess the impact of three biorational insecticides (spinosad at 30-7.5 cc/hL, mineral oil at 2000-250 cc/hL, and potassium salts of fatty acids at 1500-375 cc/hL) and two entomopathogenic fungi (Alternaria murispora and Alternaria destruens applied at 1.0 × 10, 5.0 × 10, and 2.5 × 10 conidia mL) both individually and in combination on C. vittata adults. All treatments were conducted at 25 ± 1 °C, with mortality recorded over 10 days. Conidial germination was highest for A. murispora with mineral oil (98.4%). Alternaria destruens showed consistently high germination across treatments. At 100% concentration, A. murispora + mineral oil and A. destruens + mineral oil treatments achieved 96.67 and 92.00% mortality, respectively. Median survival times (MST) for A. murispora were 6.0 days at 100% concentration, increasing to 10.0 days at lower concentrations, while A. destruens had a consistent 10.0 days MST. LC for A. murispora was 1.3 × 10 conidia mL alone, increasing to 2.2 × 10 with spinosad, but remained 1.7 × 10 with potassium salts of fatty acids. For A. destruens, LC was 4.2 × 10 conidia mL alone, decreasing to 1.5 × 10 with mineral oil, and 3.1 × 10 with potassium salts of fatty acids. Combining A. murispora with mineral oil and potassium salts of fatty acids enhanced efficacy against C. vittata.
甜菜跳甲，卡西达 vittata 维尔。（鞘翅目：叶甲科），是摩洛哥甜菜作物的主要害虫，尽管存在环境问题，但主要通过化学杀虫剂进行防治。我们的目的是评估三种生物源杀虫剂（多杀霉素 30 - 7.5 毫升/百升、矿物油 2000 - 250 毫升/百升、脂肪酸钾盐 1500 - 375 毫升/百升）和两种昆虫病原真菌（鼠耳链格孢和毁灭链格孢，分别以 1.0×10、5.0×10 和 2.5×10 个分生孢子/毫升的浓度施用）单独及组合使用对甜菜跳甲成虫的影响。所有处理均在 25±1℃下进行，记录 10 天内的死亡率。鼠耳链格孢与矿物油组合时分生孢子萌发率最高（98.4%）。毁灭链格孢在各处理中萌发率一直较高。在 100%浓度下，鼠耳链格孢 + 矿物油处理和毁灭链格孢 + 矿物油处理的死亡率分别达到 96.67%和 92.00%。鼠耳链格孢在 100%浓度下的中位存活时间（MST）为 6.0 天，在较低浓度下增至 10.0 天，而毁灭链格孢的 MST 始终为 10.0 天。鼠耳链格孢单独使用时的 LC₅₀ 为 1.3×10⁶ 个分生孢子/毫升，与多杀霉素组合时增至 2.2×10⁶ 个分生孢子/毫升，但与脂肪酸钾盐组合时仍为 1.7×10⁶ 个分生孢子/毫升。对于毁灭链格孢，单独使用时的 LC₅₀ 为 4.2×10⁶ 个分生孢子/毫升，与矿物油组合时降至 1.5×10⁶ 个分生孢子/毫升，与脂肪酸钾盐组合时为 3.1×10⁶ 个分生孢子/毫升。将鼠耳链格孢与矿物油和脂肪酸钾盐组合可增强对甜菜跳甲的防治效果。
