New technology for prevention and control of apple leaf roll moth

New technology for prevention and control of apple leaf roll moth

In August, the tower-shaped green peach is in the new shoot growth period. On the tower-shaped peach in the green belt of Pingyuan county, 30% of the new shoots of peach trees are damaged by apple leaf roll moth (figure 1). The small apple leaf moth spins the leaves of the peach tips together, feeds from them, eats the leaves into a notch or network, and excretes its feces in the leaf net (figure 2) [Yoshama Huayao].

Fig. 1 damaged peach tips

Fig. 2 peach tip with worm net

Apple small leaf moth, alias Spodoptera litura, yellow leaf roll moth, skinworm, etc., pests of the family Lepidoptera. The adult body is 6-8 mm long and the body color is yellowish brown. There are two dark brown twill stripes on the leading edge and the outer edge of the forewing, one of which is obviously broadened when it reaches the central part of the wing from the leading edge to the posterior edge. There is a small brown pattern at the shoulder corner of the posterior edge of the forewing and near the top corner of the leading edge. The egg is flat and oval, yellowish and translucent, and dozens of eggs are arranged into fish scales. The body of the larva is slender, the head is small and yellowish, the small larva is yellowish green, and the big larva is emerald green. The pupa is yellowish brown, with two rows of spines on the back of the abdomen, a small and dense row below, and 8 hooked hairs at the end of the tail.

The small apple leaf roll moth is one of the main pests in peach orchard. Three generations a year occurred in the plain, and the larvae overwintered at the skin seams and saws of the branches. In spring, peach trees and other fruit trees sting when they sprout, endangering new buds, tender leaves and flower buds. After setting fruit, they nibble on the pericarp near the two fruits, forming scars and dents, affecting the quality of the fruit. Adults have the characteristics of daytime and night, have phototaxis, and have a strong tendency to sweet and sour liquid. Trichogramma is its natural enemy. The main harmful symptoms are as follows: the larvae spit silk-rimmed leaves and lurk in the affixed leaves (figure 3), and the new leaves suffer the most. When the fruit is slightly larger, the leaves are often attached to the fruit, gnawing on the peel and pulp to form a residual secondary fruit. The larvae (Fig. 4) have the habit of harming the fruits, and one larva can harm 6 and 8 peach fruits.

The safety control measures of apple leaf moth are as follows: first, scraping: before the sprouting of the fruit tree, scrape off the rough skin and warped skin of the trunk and the saw mouth, so as to eradicate the overwintering larvae. The second is to shovel: before the fruit tree sprouts, the whole orchard sprays 3-5 Bomedo stone-sulfur mixture or 45% stone-sulfur mixture crystal 40-60 times, killing the remaining overwintering larvae. The third is scissors: combined with the harmful characteristics, when pruning in summer, cut off the apple leaf moth bud in time to eliminate the pests. The fourth is to lure: make use of its tendency to prepare sugar and vinegar solution (V sugar ∶ V liquor ∶ V vinegar ∶ V water = 5 ∶ 5 ∶ 20 ∶ 80), which has been put in canned bottles or small pots since June, hanging in the crown of trees, hanging 1 million per mu to attract the adults of apple leaf roll moth. The fifth is to release Trichogramma: Trichogramma is the natural enemy of apple roll moth. Trichogramma is released 3-4 days after the spawning peak of overwintering adults, once in 5 days and 4 times in succession, which can achieve no harm for the whole year. Sixth, treatment: after falling flowers and the peak incubation period of the first generation eggs, biological preparations or bionic pesticides and other safety agents are selected for control. 25% thiazuron 1 500 × 2 000 times or 0.5% toosendanin EC 500 × 1 000 times or Beauveria bassiana 100 million / ml and so on.

Fig. 3 affixed with leaves on peaches

Fig. 4 small apple leaf roll moth larva