Control of seed rot of loquat

In recent years, loquat foot rot has occurred seriously in some places, which has brought a serious threat to loquat production. According to the investigation, Luoyangqing and Dahongpao are the most susceptible to the disease. At the initial stage of the disease, the base of the main stem first rotted, and then gradually developed to the upper branch, and the diseased tissue gradually expanded from the xylem around the pith. The seriously diseased plants showed acute rot of branches and stems, which led to the rapid withering of upper branches and leaves. It takes only a few days for the tree with larger crown to wither in summer, the old tree with larger crown lasts about 1 year from disease to death, and a few trees can last for more than 2 years. After young trees in the affected area are infected, the mortality rate is as high as more than 80%, and the first fruit trees are about 73%. The following measures can be taken for prevention and control:

Luoyang green varieties were selected in the experiment. Diseased trees in early fruit stage and full fruit stage were treated with different pesticides and different application methods according to the degree of disease, including heavy, medium, light and healthy plants (control).

Before application, the soil within the F crown dripping line of the diseased plant was first loosened, with a depth of 15ml / 30cm, and then the following drugs were selected for prevention and control: (1) 50 times of carbendazim and topirazine, 0.5 kg of carbendazim per plant, evenly sprinkled on the loose soil under the crown, and turned into the soil; (2) 100 times of formaldehyde solution of 50,70kg per plant; (3) 100fold solution of formaldehyde, 70kg of each plant. (4) injection of 100-fold solution of formaldehyde and 50-fold solution of topiramate into the tree stem (the base of the trunk was inclined downward and drilled 5cm to 7cm deep, then the hole was sealed with clay 10 minutes after pressurized injection).

The results showed that the above control methods had no control effect on seriously diseased trees, had better control effect on moderately diseased trees, and had significant control effect on diseased trees and health care of healthy trees. Carbendazim and topiramate were injected with 0.5 kg root per plant and 50 times liquid rod injection. Thus it can be seen that attention should be paid to early drought prevention and treatment of this disease, and soil application of 0.5 kg of carbendazim and topiramate 50 times solution per plant should be used in the early stage of the disease.