What are the control methods for pea bud blight?

The green beans and sprout vegetables from peas are very popular with consumers. However, during production, quality and yield are often affected by some physiological disorders and pathogen invasion. For example, bud blight, also called wet rot or head rot, has two very obvious symptoms,

One is that at 2~6 cm from the top of the tender stem, a water-soaked diseased condition appears. When the climate is dry, the decayed part quickly shrinks and dries, hanging at the top of the stem. When rainfall occurs or air humidity rises again, the diseased part will again show wet rot symptoms;

The second is that young pods become diseased. Around the pod, a gray-white downy mold layer grows, with black granular sporangiophores and sporangia interspersed in the middle. Later, the pods turn withered yellow. The diseased pods spread from the base to the pod stalk. When humidity is high, many infected pods can be seen with gray-white downy, half-withered yellow peas.

Causes of the disease

First, low temperature, insufficient light, and high humidity induce the disease;

Second, mycelium remaining in the soil or zygospores produced to overwinter provide the pathogen;

Third, there are wounds on pea plants that the pathogen can invade; fourth, wind and rain can accelerate the spread of the pathogen; fifth, insects help spread the disease.

Prevention techniques can start from agricultural control and chemical control respectively.

In terms of agricultural measures, first, peas should not be planted continuously in the same field, and crop rotation should be practiced, preferably rice-upland rotation; second, for fields with higher fertility, the density should be appropriately reduced to prevent shading; third, carefully prepare ditches and beds and drain promptly; fourth, during drought, strictly prevent flooding irrigation. Pay attention to “dry flowers, wet boards”, that is, maintain ventilation and light transmission during flowering to reduce humidity, and ensure sufficient soil moisture during pod setting, maintaining moist management.

In terms of chemical control, first, at the early stage of the disease, spray 64% oxadixyl mancozeb wettable powder at 400~500 times dilution; second, 75% chlorothalonil wettable powder at 600 times dilution; third, 58% metalaxyl mancozeb wettable powder at 500 times dilution; fourth, 70% phosethyl-Al mancozeb wettable powder at 500 times dilution; fifth, when resistance to certain fungicides develops, 69% dimethomorph mancozeb at 1000 times dilution can be used.