The symptoms of peanut root rot (commonly known as rotten buds and roots) are short plants, yellowing leaves, drooping petioles, withered leaves and death of diseased plants in 7 ~ 10 days. Underground roots and taproots are rat-tailed, with few fruits and short plants.

The symptom of peanut stem rot (also called "seedling drop disease") is that cotyledons are soaked at seedling stage to make them brown rot, and then the underground roots at the base of the stem or near the ground are soaked to produce yellow-brown water residue-like lesions, which gradually expand and spread to the periphery of the stem into annular lesions. With the spread of disease, the whole plant withered and died. In other growth stages, the disease site is mostly at the base of the stem near the ground, and the symptoms are similar to those at seedling stage. After peanut sowing, the pathogen mainly invades from the wound, and the peak of the disease is in early July. There is a lot of rain at seedling stage, and the soil temperature is high. Especially after heavy rain, the temperature rises rapidly, and the stem rot is more serious. Too low or too high temperature is not conducive to the occurrence of the disease.

In the process of cultivating peanut bud, rotten buds, rotten roots and other rotting phenomena often occur. The main reasons are as follows:

1. Beans themselves carry germs;

2. The disinfection of bean sprouts containers and utensils is not strict;

3. The temperature of raw bean sprouts is too high;

4. Not watering in time, the water quality is not clean, and the air is polluted.

Selection criteria of fungicides in peanut bud

1. It needs broad-spectrum and efficient sterilization effect, and a disinfection products can kill pathogenic microorganisms such as bacteria, fungi and molds;

2. It does not produce bacterial drug resistance and meets the requirements of long-term reuse;

3. The requirements are food-grade disinfectants, reaching the level of edible harmlessness;

4. It needs mature application in planting.