How to identify and control navel orange black spotted oyster?
Black spotworm, also known as black spot mesenchymal insect, occurs in The navel orange producing areas of China.
(1) Symptoms of harm The black spotted borer mainly harms the leaves, twigs and fruits of the navel orange, and feeds on the leaves, fruits and twigs in clusters of larvae and adults. Yellow spots appear in the damaged area of the leaves, which can turn the leaves yellow in severe cases. Yellow spots appear in the fruit, and ripening is delayed, which affects the quality and appearance of the fruit in severe cases. Black spotworms can also induce coal pollution.
(2) Life habits Black spotted insects occur in 3-4 generations per year, and the field generations overlap, and mostly female adults and eggs overwinter. In the field, first-instar nymphs appear in late April, three peaks occur in early July, mid-September and mid-October, and from December to March of the following year, when the average daily temperature is below 13°C, the first-instar nymphs are at low tide. The number of female adults is consistently higher than that of first-in-one nymphs throughout the year, especially from November to March of the following year. Closed and weakly growing trees favor the reproduction of black spotted ants.
(3) Prevention and control methods (1) Pharmaceutical prevention and control. During the nymph season, spray the drug once every 15-20 days for a total of 2 sprays. The potion is the same as the yakniform worm. (2) Use of natural enemies for prevention and control. The whole-breasted oligopod ladybird, the red-spotted lip ladybird, the long-wisped shield aphid wasp and the red-spotted mold are the natural enemies of the black spotted oyster, and attention should be paid to protection and utilization. (3) Agricultural control. In winter, the garden is completely cleared, and insect branches, dry branches and closed branches are pruned to reduce the source of insects and improve ventilation and light transmission conditions.
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