What Causes Yellowing Leaves on Cowpea Plants? Detailed Explanation of Prevention and Control Methods
Cowpea is one of our common vegetables, and spring and summer are its market season, but during the cowpea growing period, many farmers have reported finding that cowpea leaves turn yellow, seriously affecting the growth of cowpea. So what are the causes of yellowing cowpea leaves? How should they be prevented and controlled? Let's take a look together.
1. Symptoms
Yellow leaves on cowpea generally occur in two situations. One is yellowing of the lower leaves, which drop off very easily, and the condition also spreads upward, with plant death occurring. Another is yellowing of the new leaves at the top, accompanied by flower and pod drop. There is also a relatively rare situation in which the plant does not die, but its leaf veins turn yellow.
2. Causes
There are mainly three causes of yellowing cowpea leaves. One is infection by root rot, a soil-borne disease. The pathogen attacks the root system in the early stage, causing poor plant growth, and the lower leaves gradually turn yellow. During the high-temperature, strong-light period at noon, the plant wilts, recovers in the morning and evening, and finally dies. The second is a lack of trace elements. Yellowing of the top leaves is caused by iron and zinc deficiency, while yellowing of the new top leaves is sometimes caused by sudden clearing after rain or changes between cold and warm weather. Yellowing of the leaf veins is caused by poor plant growth. This situation does not cause plant death and is mainly caused by excessively high temperature, poor root growth, and insufficient fertilizer and water.
3. Prevention and Control Methods
For cowpea root rot, a combination of physical control and chemical control can be adopted. When planting, soil should be disinfected and sterilized together with land preparation to eliminate the pathogen. When the disease occurs, carbendazim can be used as a root drench, with good results. For trace element deficiency, organic fertilizer can be applied as a base fertilizer to increase the soil organic matter content, improve soil structure, and supplement various trace elements for the plant. Later, foliar fertilizer spraying can supplement the trace elements the plant lacks and can alleviate leaf yellowing. For yellowing leaf veins, watering and fertilizing should be done reasonably to enhance the plant's resistance and make the root system grow strong, so as to avoid yellowing of leaf veins and premature leaf aging.
The above is an introduction to the causes of yellowing cowpea leaves and the prevention and control methods. We hope it can help you. To learn more related knowledge, please keep following us.