The new leaves of Lagerstroemia indica are white. I don't know what disease or bug it is.

Powdery mildew of Lagerstroemia indica is a common disease on Lagerstroemia indica, which is seriously harmful in some areas.

symptom

Powdery mildew of Lagerstroemia indica occurs on tender leaves and buds. In spring and summer, tender buds and leaves are distorted and covered with a layer of white powder after being infected. When the leaves are spread out, they will get sick. The diseased spots on the leaves are round and covered with white powder. In severe cases, they can also be connected together. The diseased leaves fall off in advance, which affects the growth. After the flowers are infected, the surface is covered with white powder, and the flower spikes are deformed, losing ornamental value.

1. Horticultural control: Lagerstroemia indica has strong germination ability. In winter, seriously ill adult trees can cut off all the branches of the year, remove the diseased leaves and branches, and reduce infection. Family potted Lagerstroemia indica should remove the diseased leaves in time and put the potted flowers in a ventilated and light-transmitting place.

2. Chemical control: 500 times 80% zineb wettable powder or 1000 times 70% thiophanate methyl can be sprayed. From mid-May, every 10 day 1 time, 3-4 times.