Leafminer moths have always been one of the pests that harm citrus, and the high incidence period is from July to August every year, because these two months are the highest temperature in summer, especially in orchards with many taps and unevenness, leafminer moths breed faster, and once the control is not timely, it will erupt in a large area.
Leafminer moths are mainly harmful to citrus leaves and branches, the most obvious symptom is that the leaf surface has a clear "ghost symbol" pattern, because the larvae will sneak on the young leaves and young stems of citrus trees to eat leaf flesh, leaving irregular silver-white lines, these patterns will appear.
Citrus trees that are harmed by leafminer moths often have curly and hardened leaves with white lines attached to the surface, and then gradually fall off as the disease worsens, affecting the normal photosynthesis of citrus. Serious will lead to poor growth of new branches, and even endanger the fruit, more odious is the place where the leafminer moth eats, if not prevented in time, it may also cause ulcer disease, and the affected leaves also provide a wintering place for red spiders, leaf curling moths and other pests.
The degree of occurrence of citrus leafminer moth is related to climatic conditions, environmental conditions, citrus varieties, extraction period, citrus age, disease and pest control, soil fertilizer water management and other factors, such as high temperature and high humidity climate is conducive to the incidence of leafminer moths; planting density, low-lying orchards are more harmful; for citrus tree age, the degree of harm of seedlings is the most serious, followed by young trees; overgrowth in orchards, drought irrigation is not timely, orchard water for a long time will increase the degree of harm of citrus leafminers. In addition, all the factors related to the strength of citrus trees in production affect the occurrence of leafminer moth infestations to a certain extent.
At the peak of the citrus leafminer moth, fruit growers should take precautions in advance to avoid causing different economic losses.
1. Control the application of fertilizer water during summer and autumn shoot extraction, remove and burn the uneven young shoots that are pumped prematurely or late in the field, so that the summer and autumn shoots are pumped neatly and robustly, so as to reduce pest feed, reduce insect population density, and reduce the number of sprays.
2, vigilance against wind and rain days, wind and rain will bring a large number of wounds to the tree body and provide infection conditions, should be sprayed before the wind and rain to spray protective agents to suppress the pathogen base, after the wind and rain and then play systemic drugs to supplement prevention and control.
3. The natural enemies of leafminer moths are used to control their numbers, mainly grasshoppers, ants, and parasitic wasps. How to take advantage of these predators? According to their habits, we should create conditions suitable for their survival as much as possible.