紫薇白粉病的研究

Study on Powdery Mildew of Grand Myrtle

紫薇白粉病病原菌分生孢子在 5～ 30℃的温度范围中均可萌发 ,以 2 5℃为其最适萌发温度 ;孢子萌发需要较高湿度条件 ,在 10 0 %的湿度条件下萌发最好。在 2 5℃下接种病害的潜育期为 4d ,病原菌主要侵染嫩叶 ,易从叶背面侵入。叶片的着生方位与发病关系不大。防治结果表明 ,粉锈宁 10 0 0倍液、15 0 0倍液 ,甲基托布津 80 0倍液均有良好的防治效果 ,相对防治效果达 80 %以上 。

The pathogenic fungus of mildew myrtle Grand powdery is Uncinula austruliana.Conidia can germinate in the temperature rang of 5～30℃,the opium is 25℃;Rh100% is good to the germination of conidia.The latent period is 4 days,and the fungi infected tender leaves mostly.There is little relation between the occurring of diseases and the orientation of the leaves.It showed that triadimefon and thiophanate have good effect on the disease.