What are the common diseases and insect pests of plum trees? Introduction of key points of prevention and control technology

Plum tree is one of the more common fruit trees in life, especially in the past, peach trees, plum trees almost every family has planted. Plum trees are more vulnerable to diseases and insect pests in the growth process. Today, we mainly introduce the common diseases and insect pests of plum trees, key points of prevention and control techniques and other details.

What are the common pests of plum trees?

1. Plum fruit borer

Plum fruit borer is a pest of Lepidoptera, small leaf roller family (more in 40-50° N), which is the most serious pest to damage plum fruit, with a killing rate of 80%-90%. The damaged fruit often flows out teardrop-like pectin at the wormhole, cannot continue to develop normally, and gradually turns purple and falls off. Because of its worm path full of red worm dung, it is also called "bean paste stuffing" figuratively.

2. Red Spider

The red spiders that harm plum trees are mainly adults and nymph of hawthorn red spiders, which suck leaves and the juice of initial germination, resulting in new buds unable to continue to germinate. After serious damage to leaves, the whole leaves turn brown and fall off. In July and August of the big occurrence year, most leaves fall off, sometimes causing two blossoms. The seriously damaged plum trees not only fail to mature in the current year, but also greatly affect the flower bud formation of the current year and the yield of the next year.

3. Bacterial perforation disease

The disease first produces water-like spots on the pericarp of the diseased fruit with the dermatome as the center, and when it expands to 2mm, the center of the spot turns brown, and finally forms a nearly round, dark purple spot with water-like halo ring at the edge, slightly concave in the middle, hardened rough surface, and irregular cracks, up to about 35 mm. When the humidity is high, yellow overflow can occur in the diseased part, and the diseased fruit falls off early. High temperature and high humidity are beneficial to infection and aggravation of disease. The disease was more serious in orchards with weak tree vigor, poor drainage and ventilation or excessive nitrogen fertilizer application.

II. Introduction to key points of common diseases and insect pests control technology of plum trees

1. Key points of control techniques for plum fruit borer

The key stages of the disease were adult stage and oviposition stage of each generation and mature larva stage of the first generation. Spraying 90% trichlorfon 0.8% solution, 50% malathion 1% solution, 50% dichlorvos. 50% phoxim 1%~1.5% solution was applied to plum trees before physiological fruit drop and under canopy. At the end of flower drop (95% flower drop), when the small fruit is the size of wheat grain, spray the first time, use dichlorvos, dichlorvos, sumiding and laifuling, spray once every 7~10 days. From the point of view of integrated control, biological agents can also be used to treat the soil under the tree crown, such as Beauveria bassiana. After autumn, the fallen fruit should be swept away to reduce the source of insects in the following year.

2. Control techniques of red spiders

According to the living habits of red spiders, in field management, reasonable intercropping, timely deep turning of tree disk or tree disk buried soil, reasonable pruning, appropriate fertilization and irrigation. Soil methods can also be used to control, such as garlic juice spraying or washing powder mixed with sulfur mixture and other methods. At the same time, natural enemies should be protected to give full play to their natural control of pests.

3. Prevention and control technology of bacterial perforation

Strengthen orchard comprehensive management, increase organic fertilizer, improve tree disease resistance.

For orchards with heavy soil and high groundwater level, attention should be paid to improving soil and drainage; selecting disease-resistant varieties, carrying out reasonable shaping and pruning, and creating good conditions for ventilation and light transmission.

Cut off diseased branches in winter, scrape off diseased spots on branches in early spring and smear wounds with 25~30 degree sulfur mixture to reduce initial infection sources.

Pesticide control: Diammonium, streptomycin, neophytin and thiram are sprayed at conventional concentrations, and the number of pesticide control times is appropriately increased during fruit growth.