The Occurrence and Damage of Wheat Powdery Mildew in Desert Oasis Area and the Control Efficiency Evaluation of Fungicides

【Objective】 The aim of this study is to clarify the occurrence and damage of wheat powdery mildew in different areas and screen the fungicides which have better control effectsin the hope of providing scientific basis for the prevention and control of wheat powdery mildew in desert oasis ecological area. 【Method】 General investigation method was used to investigate the occurrence of powdery mildew in different ecological zones. The efficacy test was conducted by randomized blockdesign, and the occurrence of wheat powdery mildew was surveyed in each plot at fixed points. 【Result】 The occurrence and damage of wheat powdery mildew in Hotan, Kashgar and Aksu regions were higher, with disease index of (35.65±0.83),(35.63±1.04) and (30.82±0.91), respectively, significantly higher than that in Changji Hui Autonomous Prefecture and Tacheng region, with the disease index of (9.95±0.71) and (6.00± 0.46), respectively. 240 g/L mefentrifluconazole-pyraclostrobine EC and 19% picoxystrobin-propiconazole SC had the best control efficacy against wheat powdery mildew with 84.94% and 82.77%, respectively. The control efficiency of 23% kresoxim-methyl-epoxiconazole SC, 430 g/L tebuconazole SC, 42% metrafenone SC, 43%fluoxastrobin-tebuconazole SC, 48% difenoconazole-azoxystrobin SC, 75% trifloxystrobin-tebuconazole WG and 40% myclobutanil WP floated in the range of 64.57% to 71.12%. 【Conclusion】 The occurrence and damage of wheat powdery mildew in southern Xinjiang is significantly severer than that in northern areas, with the occurrence degree of 3 to 5. The occurrence of powdery milder in northern Xinjiang was mostly at degree 1 to 2. 240 g/L mefentrifluconazole-pyraclostrobine EC, 19% picoxystrobin-propiconazole SC, 23% kresoxim-methyl-epoxiconazole SC, 430 g/L tebuconazole SC, 42% metrafenone SC, 43% fluoxastrobin-tebuconazole SC, 48% difenoconazole-azoxystrobin SC, 75% trifloxystrobin-tebuconazole WG and 40% myclobutanil WP can effectively control wheat powdery mildew and are safe for wheat growth. They can be applied in rotation in wheat fields.