How to identify and control navel orange bran flap beetle?
Bran flake borer, also known as gray spotted beetle, occurs in China's navel orange producing areas.
(1) Hazard symptoms The bran flap mainly harms the navel orange branches, leaves and fruits, and the injured part of the leaf shows pale green spots, and the injured part of the fruit shows yellow-green spots, affecting the quality and appearance of the fruit. Bran flap borer can induce coal pollution disease, so that the tree body is covered with a layer of black mold, affecting photosynthesis, thereby weakening the tree potential, and even leading to the death of branches and leaves.
(2) Life habits Of the chaff flap, 3-4 generations occur in the Gannan region of Jiangxi Province, overwintering with female adults and eggs, and there are also a few second-instar nymphs and pupae overwintering. Generations overlap in the field, with generations of first- to second-instar nymphs occurring in April-June, July-August, August-October, and November to April of the following year, but the most harmful is in August-October. Female adults can reproduce parthenogenetically and lay eggs for up to 3 months. After hatching, the nymphs feed under the mother or crawl out of the mesohus for fixed feeding, and secrete white wax to form a white cotton-like powder to cover the worm body. The first generation of nymphs mainly feed on leaves, and the second and third generations of nymphs mainly harm fruits. Bran flakes prefer to inhabit shaded or poorly lit branches and leaves, especially where there are cobwebs or dust covering the most. The same tree, first endangering the branches, and then spreading to the fruit and leaves, the leaf surface is more than the leaf back worm, and the fruit has more depressions.
(3) Prevention and control methods (1) Pharmaceutical prevention and control. Catch the first to second instar nymphs during the peak period and spray the spray once every 15-20 days, a total of 2 sprays, the same as the arrow tip of the insect. (2) Use of natural enemies for prevention and control. Japanese square head beetles, grasshoppers, long-tasseled aphid wasps and golden aphid wasps are natural enemies of bran aphids, and attention should be paid to protection and utilization. (3) Agricultural control. Strengthen cultivation management, increase the application of organic fertilizer, improve soil structure, enhance tree potential, and improve the insect resistance of plants. In winter, the garden is completely cleared, and severe insect branches, dry branches and closed branches are cut off to reduce the source of insects and improve ventilation and light transmission conditions.