Control of powdery mildew of mango

Mango in flowering, young fruit stage and tender leaf stage, prone to powdery mildew, control is not timely, will be a large number of fruit drop, resulting in reduced yield.

Mango powdery mildew is a fungal disease, which mainly harms inflorescences, young fruits and tender leaves. Some scattered white mildew patches appear on the susceptible organs, and then a layer of pale mildew powder is formed. Flowers and sepals are most susceptible to disease, and petals are more resistant. Flowers and stalks stop growing after infection, can not blossom, and fall off after 2-3 days; on young fruits, the mildew powder layer is often covered with fruit surface, and the diseased fruits usually fall off when they grow to the size of fingers; lightly diseased fruits can continue to grow, sometimes the epidermis of the diseased parts crack and form cork tissue; amorphous patches occur after mature fruits are infected. The epidemic is easy to occur when the temperature is about 20 ℃ ~ 25 ℃.

Cultivation and control

1. Select disease-resistant varieties.

2. Strengthen management in the process of cultivation.

3. Clean the orchard thoroughly before flowering after fruit picking, and do a good job in cleaning the orchard.

Chemical control

Pharmaceutical sulfur agents such as stone sulfur mixture, colloidal sulfur, especially fine sulfur powder have a special effect on the prevention and treatment of this disease. In the new shoot stage, stone-sulfur mixture can be sprayed (0.4-0.5 Baume in spring and autumn, 0.8 Baume in winter, 0.2-0.3 Baume in summer, about 5-7.5 kg per tree), sulfur powder and wettable colloidal sulfur can also be sprayed, but the cost is high. It is appropriate to spray sulfur powder or wettable colloidal sulfur (diluted 150 times with water) before and after flowering for the first time and the second time when the petals fall off into small fruits. The sulfur powder should be fine, and the control effect will decrease if the sulfur powder is too large, taking the sieve hole of 300 to 325 as the standard. Spraying should be carried out in the morning when the dew is not dry.

In addition, the following agents can also be used for control: ① 50% methyl thiophanate wettable powder 1500 times or carbendazim 1500 times; ② 50% zinc wettable powder 1000 times; ④ 50% chlorothalonil wettable powder 500 times 800 times; ⑤ 50% carbendazim wettable powder 800 times spray.