What medicine is used to roll pear leaves?

40% methamidophos EC 1000 times solution+1.8% avermectin EC 1000 times solution.

The main reasons for yellowing and leaf rolling of pear seedlings are: pear seedlings were not watered in time when they were planted, or the weather was dry and they were not watered in time. Fertilization too early, too much, or too close to the tree head, or too high concentration causes root rot, resulting in pear seedlings drying up and falling leaves. The concentration of chemical solution sprayed by pear seedlings is too high, which causes the leaves of the plants to turn yellow. The soil has heavy salinity, low terrain, high groundwater level, high soil viscosity, poor drainage and frequent irrigation.

Combining winter fertilization and garden cleaning, before the early winter frost comes, the topsoil under the canopy should be deeply ploughed 10 ~ 15 cm to freeze the overwintering larvae, and Bubomei 5-degree sulfur mixture should be sprayed before germination. In the growth period of spring shoots and summer shoots, the leaves damaged by larvae should be cut off in time and burned centrally to reduce the source of insects.

In the germination period of spring shoots and summer shoots, chemical control should be carried out to poison ovipositing adults and newly hatched larvae, and the compound effect of internal absorption strong penetration insecticide and gastric toxicity insecticide is the best. Optional chemicals are: 40% methidathion EC 1000 times solution+1.8% avermectin EC 1000 times solution.

Improper prevention of pear rust, which is difficult to treat in the later stage, infects leaves and fruits, leading to tree weakness. First of all, this pathogen parasitizes cypress trees for the winter. Pear trees should stay away from cypress trees. If there are cypresses nearby, be sure to spray them in early spring.

In the growth period of spring shoots and summer shoots, it is found that the leaf gall midge is harmful, so the damaged shoots should be cut off or the leaves should be destroyed in time to reduce the insect source and the emergence period of adults. 3% phoxim powder or 450 times of 48% Lethbone EC should be sprayed under the canopy to kill adults. Before topping, spray 800 times 50% phoxim EC or 1000 times 80% dichlorvos EC and 1000 times 40% dimethoate EC on the ground under the canopy.

Spraying trees with 2500 times solution or 3000 times inactivating solution of chlorfenapyr, and spraying again every 15-20 days, for a total of 1 time. Pear trees that are lightly cut with many flowers should be pruned again, mainly by thinning weak branches, diseased dead branches and too dense branches, adjusting the load of fruit trees and determining the amount of flowers according to the amount of fruit left.

The damaged leaves gradually turn green, the texture is hard and brittle, and finally turn black and fall off (the texture is slightly soft after aphid damage, which is not easy to fall off), and in severe cases, it can also cause bald tips. All cultivated varieties have been damaged to varying degrees. The leaves of the damaged pear trees fall off in spring and summer, and the autumn shoots are slender, with poor flower bud differentiation, and generally do not bear fruit in the second year.

The amount of flowers left is 65,438+0-2 times more than that of reserved fruits, and only 65,438+0 flower buds are left on each fruit table to avoid removing too many flower buds. A series of flower buds formed by the growing branches of varieties that are insensitive to pruning should be appropriately shortened to make the fruiting branches close to the trunk and promote the long branches to prepare for future fruiting.