What to Do When Bean Leaves Turn Yellow? Causes and Control Methods

Many farmers encounter the problem of yellowing bean leaves. Whether it is new leaves turning yellow or old leaves at the bottom turning yellow, there are many causes of leaf yellowing. If effective measures are not taken in time, it can even cause total crop failure in severe cases. Below, for bean leaf yellowing under different circumstances, I will recommend several effective measures for everyone.

1.Yellowing of new leaves

If bean plants are kept for a long time in weather that turns suddenly clear after rain, have weak root systems, or bear too much fruit, the new leaves near the growing point at the top of the plant are prone to turning yellow or white. This is mainly caused by iron and zinc deficiency.

Control measures: Once bean new leaves turn yellow due to a lack of trace elements, be sure to spray trace element fertilizer on the leaves in time, which can quickly and effectively alleviate the symptoms; at the same time, farmers are advised to pay attention to supplementing organic matter and trace elements when applying base fertilizer for the next crop, so as to avoid adverse effects on the next crop due to a lack of available trace elements in the soil.

2.Yellowing between leaf veins

Yellowing between veins is likely to occur on older leaves in the middle and lower parts. It mainly shows as yellowing between the leaf veins, but it will not cause plant death. Yellowing between leaf veins is mainly caused by two reasons. One is a lack of available magnesium in the soil. The main symptom of magnesium deficiency in plants is chlorosis and yellowing between leaf veins, and because magnesium ions are highly mobile in plants, it mostly occurs on leaves in the middle and lower parts of the plant; the other reason is that the plant grows weakly and declines early. Too high a greenhouse temperature, poor root growth, and unscientific fertilizer and water supply can all lead to weak plant growth, thus causing yellowing between leaf veins.

Control measures: For chlorosis and yellowing between leaf veins caused by magnesium deficiency, spray magnesium-containing foliar fertilizer in time, and also pay attention to supplementing organic fertilizer and magnesium fertilizer when applying base fertilizer; for plants with poor growth, microbial fertilizer such as Kingenta/Wofute/Aolindan can be applied to promote rooting and regulate their growth. During the topdressing period, apply fertilizer and water reasonably, and prevent chlorosis and yellowing between leaf veins through comprehensive management.

3.Yellowing of bottom leaves

Cause analysis

1. Bean root rot, commonly known as “red root disease.” This is a soil-borne disease. In the early stage, pathogens infect the root system, the plant suffers from poor nutrition, the bottom leaves turn yellow, the plant wilts at noon and recovers in the morning and evening, and finally the plant dies.

2. Lack of trace elements. The leaves at the top growing point appear yellow-white, caused by iron and zinc deficiency. Yellowing of new leaves at the top generally occurs under conditions such as sudden clearing after cloudy weather, poor root growth, weather turning from cold to warm, and the plant bearing too much fruit earlier.

3. Poor plant growth. This situation will not cause the plant to die. It is mainly because poor plant growth causes the middle part between the veins of the middle and lower leaves to turn yellow, which can easily lead to early decline of the plant. For example, too high a greenhouse temperature, poor root development, root damage, and unscientific fertilizer and water supply can all cause similar situations.

Control methods

1. Bean root rot can be treated by drenching the roots with chemicals. Optional chemicals: Jiufuyu, Jinmianwei, Xiumiao, Dijunsha, etc., combined with Saoxi, Xisha, Jinmeizuo, Bilu, etc.

2. In adverse weather and in the middle and late stages of plant growth, foliar spraying can be used: Xisha, Jinmeizuo, Bilu, Bijunsha combined with Kuhuang Qiaolu, Wandaihong, Biliaao, etc., which can effectively alleviate the yellow-white color of new leaves at the top.

3. Enhance plant resistance, cultivate strong root systems, and water and fertilize reasonably (Lvyuan balanced fertilizer, Dagezi 20-20-20, Miaoguo, Yimujin, etc. can be selected) to prevent yellowing between leaf veins and leaf early decline. It can be used together with Huishengye + Teyougen, applied by flushing 2-3 times.

Alright, the above are the causes of bean leaf yellowing and the solutions. Farmer friends, when you find bean leaves turning yellow, be sure to identify the cause in time and prevent and control it early, so as not to cause the death of the entire plant. Some of the above control measures are analyses for leaf yellowing in different parts, and everyone can apply the right remedy for the condition.