The twill nocturnal moth belongs to the lepidoptera pest, mainly larvae, is an omnivorous and gluttonous pest, harmful to crops are very many, such as melons, legumes, all kinds of vegetables and so on. In citrus orchards, larvae bite new leaves, buds, and young fruits of citrus. The larvae have a group feeding habit, the growing larvae also have the habit of migrating in groups, diving out of the day and night, and during the day they like to hide on the ground and grass in the near future, and come out to eat in the evening, the larvae eat a large amount, and will eat the young shoots overnight to only the leaf veins. Adults have strong phototropism, lay eggs on the back of the leaves, and are irregularly overlapped into egg blocks in 2-3 layers, covered with yellow and white insect body villi, and the number of eggs is very large.
The larvae eat the young leaves
The larvae eat small navel oranges
lay eggs
The twill nocturnal moth is a gap pest in navel orange orchards and generally does not cause significant harm, but in recent years, regional large-scale occurrences have often occurred on the umbilicus of Gannan, and there have been major outbreaks in some orchards from June to August 2015. This year may be due to the abnormal high temperature and little rain in spring (the average temperature in the city from January to March is 2.8 °C higher than the same period of the calendar year, and the rainfall is 5.5% less), which promotes the early occurrence of twill moths in some orchards, the rapid increase in insect volume, and some orchards in late March began to endanger new shoots and buds, and at present, some orchards endanger spring shoots and young fruits, and the insect population has a clear upward trend, and it is necessary to be vigilant against outbreak hazards.
First, strengthen monitoring
Strengthen the monitoring of insect conditions in orchards and surrounding crops, and timely grasp the dynamics of occurrence. 2. Prevention and control measures
1. Timely control of insect situation. Twill nocturnal moth larvae take a large amount of food, grow fast, more than 3 years of resistance, drug resistance is strong, found that the harm should be timely grasped in the young larval stage spray control, such as a large amount of insects, every 3-5 days and then sprayed again, control the development of insect situation. 2. Spray in the evening. Since the larva prefers to feed at night, spraying is best done in the evening after 5 p.m. 3. Spray on trees and on the ground. During the day, he likes to hide on the ground and grass roots, and the canopy and the ground should be sprayed at the same time.
Third, pesticide selection
It can be selected from 5% methyl vitamin salt 1000 times + 240 g/ liter insect mite nitrile 800 times, 5% methyl vitamin salt 1000 times + 15% indicosil 800 times, 2.5% cyfluthrin 1000 times + 40% triazole phosphorus 800 times, 4.5% high efficiency cypermethrin 1000 times + 40% triazole phosphorus 800 times.