Control method of jujube blight in spring with dense twigs which are long and difficult to shed

In recent years, jujube mad disease has a tendency to aggravate. After jujube sprouting in spring, the disease of jujube mad disease gradually appears, which should be prevented and controlled in time.

Jujube mad disease

Symptoms: after the jujube tree contracted the disease, the pedicel lengthened, which was 3-6 times that of the normal flower, and the sepals, petals and male pistils became light green leaflets, and dwarf twigs were produced between the axils of leaflet leaves to form branches; developmental branches germinated many times in a year, continuously producing small yellow-green branches and leaves, forming dense branches and leaves, which were not easy to fall off in winter; hidden buds of the whole tree branches germinated in large quantities, resulting in yellow-green fine branches; branchlets sprouted under the tree.

2. Pathogens and routes of transmission:

Phytoplasma is the pathogen of jujube madness. It belongs to non-spiral mycoplasma and is a microorganism between virus and bacteria. The jujube tree with jujube mad disease is the primary infection source of jujube mad disease. The pathogen survives in the live diseased tree and spreads the disease through ramet propagation, grafting propagation and leafhopper transmission. The experiment showed that the contact between sap friction inoculation, diseased plant pollen, seed, soil in diseased garden, diseased tree and healthy tree root could not spread jujube mad disease.

Chinese pseudo-rhomboid leafhopper, concave edge rhombus leafhopper and red flash leafhopper are the main transmission pests of jujube mad disease. Leafhopper host plants: jujube, sour jujube, pine and cypress, elm, mulberry, soybean, sesame, mung bean, juniper and so on. The above three kinds of leafhoppers are widely distributed in northern jujube producing areas, all of which are omnivorous pests and breed in large quantities in weeds. Therefore, close to the hillside, overgrown with weeds and adjacent to the pine and cypress jujube orchard, the occurrence of jujube mad disease is far more serious than the jujube orchard located in Pingchuan and clean management.

Third, hazards and preventive measures:

Jujube madness is a devastating disease. Jujube mad disease generally shows symptoms on some branches and roots and tillers, and then spreads to the whole tree. After the disease, the young trees generally died in 1-2 years, the big trees were infected, and died gradually in 3-6 years. The harm of jujube mad disease is serious, but it can be prevented and treated. Prevention and control measures:

1. Sawing off diseased branches and removing diseased plants in time: sawing off diseased crazy branches as soon as possible, reducing the source of infection, curing or delaying the disease. Root out the diseased tree and replant healthy seedlings in place.

2. Select disease-resistant rootstocks and varieties, strengthen jujube orchard management: select disease-resistant jujube varieties as rootstocks, such as Ziziphus jujuba, Maya jujube, Beijing white jujube and so on. Strengthen the management of fertilizer and water in jujube orchard, remove weeds, promote the healthy growth of jujube trees and improve disease resistance.

3. Drug treatment and rehabilitation: low-toxic and high-efficiency compound drugs "Quzhang No. 1" and "Qufan No. 2" with dual effects of killing pathogens and supplementing nutrition were used for infusion treatment.

4. Control of disease-borne leafhoppers: weeds are overgrown in jujube orchards, or intercropping sesame, wheat and corn, planting pine, cypress, mulberry, locust, etc., leafhopper reproduction and overwintering. From early May to mid-late August, insecticides were sprayed to kill leafhoppers and reduce the spread of germs.