Once clover is infected with sclerotinia disease, it will form spots on the plant. At first, it will appear light brown, and gradually the color of the spots will change from light brown to gray white. At this time, the root base will become soft rot and grow the so-called sclerotia. Light plants will be yellow, yellow star shaped, heavy wilt Yan die. The control method of sclerotinia disease is to pull up the plants and deal with them intensively to reduce the spread. Pay attention to drainage in rainy season to avoid ponding. Next is uses the common chemical pesticide - the ethylene sclerotium agent, can cause the sclerotium cell to rupture.
If the white clover is infected by virus, it is difficult to control it with medicine. Can use seed disinfection, soil treatment, killing insect vectors and other methods.
It is a kind of insect pest that lives on the back of leaves and sucks the juice of leaves. The leaves of light damaged plants will turn green, and there will be small white spots on the leaves. If the damage is more serious, the whole leaves will be pale, and the ornamental value will be greatly reduced. The control method is to check in late April. If it is found that the larvae can be sprayed with pesticide, the spraying should be even, not only on the surface and back of the leaves, but also inside and outside the plants.
The ground tiger, like its name, does great harm to the roots and buds. Some bite off the roots on the ground. They can nibble the buds from the ground and cause the plants to die. For their prevention and control, we can use venom to trap and kill them. In addition, we can also use carbofuran granules to kill them. The dosage per mu is 1500-2000g. This medicine has a long residual period and can be protected from damage 7-8 weeks after application.
It is one of the major pests of clover. From April to October every year, the butterfly begins to do evil. In the dry, hot and rainy seasons in summer, the larva can eat up the leaves, resulting in the weakening of the growth potential of the affected plants. The control can spray cyanobacteria to kill the larvae, or spray 2.5% trichlorfon powder in the morning when the dew is not dry, the dosage per mu is 3-4 Jin, the effect is ideal.
