Common Diseases and Pests of Melon and the Latest Control Methods
Melon is also called Oriental melon and apple melon, but it looks different from the Oriental melon; the Oriental melon's rind tends to be yellow, while the melon's rind is green. Strictly speaking, melon is a type of Oriental melon. Melon was originally a wild fruit, and in recent years it has been planted on a large scale. Although melon was formerly a wild fruit, it can also suffer from many diseases and pests. So what diseases and pests occur? How are they controlled? Let's take a look below!
1. Damping-off
Damping-off generally occurs during the melon seedling stage. After the melon seedlings emerge, the part of the seedling stem in contact with the ground begins to form a water-soaked area, appearing as a yellow-brown linear shape, which causes the seedlings to topple over, lack water, and finally wilt and die. It mainly occurs under conditions of low temperature and high humidity. The main pathogen is a kind of fruit rot fungus, Pythium aphanidermatum. The pathogen overwinters in the soil and diseased plant residues in the form of oospores, and can survive in the soil for a long time. In spring, it spreads through rain and wind, irrigation water, and other media. In the seedling soil, fully decomposed farmyard manure must be used, the seeds must be disinfected, and the seeds must be dressed with chemicals. After the disease occurs, chemicals such as copper-ammonium mixture can be used for control.
2. Melon stem rot
Stem rot mainly damages the stems and roots of melon. During the adult plant stage of melon, the epidermis of the root crown near the ground begins to show water soaking, gradually cracks, and has traces of peeling, then coffee-colored juice begins to seep out. In severe cases, it causes the melon to wilt and die. It mainly causes the fruit rind to dry and crack, and then produces a large number of black dot-like structures; these black dots are the conidia and microsclerotia of the disease. The main cause of the disease is prolonged high temperature and high humidity, and then a large number of wounds on the plants; after overwintering, the pathogen enters through the wounds. Continuous cropping must not be practiced; at least a rotation of more than three years must be implemented. After harvest, all diseased plant residues must be thoroughly removed, planting density must be reasonably controlled, fertilization must be controlled, and attention must be paid to draining accumulated water from the field.
3. Bacterial wilt
Bacterial wilt mainly damages the stems and vines of the melon. Bacterial wilt causes the stems and vines to begin to become thinner, and water-soaked areas also appear. The vines at the top begin to wilt, and in the later stage, due to insufficient nutrient supply, the entire plant withers and dies. If the stems and vines of dead diseased plants are cut open and the diseased area is squeezed by hand, a milky white liquid will be found flowing out. The main pathogen is Erwinia. These pathogens overwinter in the bodies of leaf-eating insects and in diseased plant residues, and in spring infect through insects and wounds on the plants. The main control method is also to avoid continuous cropping, promptly clean up diseased plant residues in the garden, and after the disease occurs, spray with agricultural streptomycin for control.
4. Melon soft rot
Soft rot mainly damages melon fruit, and occasionally also causes some damage to the vines. Like the previous three diseases, the affected parts begin to show water soaking; these water-soaked areas begin to expand, then become slightly sunken, and the affected area becomes somewhat soft. In the later stage, it begins to rot and is accompanied by a certain odor. The main harmful pathogen is the soft rot subspecies of Erwinia, which overwinters in diseased plant residues and soil, and spreads through insects, wounds, rain and wind, and all other media. Pay attention to crop rotation, remove diseased plant residues, and pay attention to drainage to prevent disease. Chemicals such as xinzhisu can be sprayed for control.
The above are four relatively common diseases of melon. It is not hard to see that most of these pathogens overwinter by attaching to diseased plant residues and soil. Then in spring they all come out to harm the fruit. Therefore, after harvest, the soil must be disinfected, diseased plant residues must be centrally destroyed, and continuous cropping must be avoided. Melon diseases must be carefully inspected and corresponding measures taken, so that melon can achieve high yield.