I suspect that kale calcium deficiency disease, which is a plant disease, mainly manifested in the leaf margins become yellow-brown to yellowish-white, and in severe cases, the leaf margins dry up.

Calcium deficiency in kale is a physiological disease, i.e. non-infectious. Causes of calcium deficiency, first, the soil calcium is insufficient; second, high temperature and humid weather affects the plant's absorption and utilization of calcium; third, long-term application of ammonium sulfate and other acidic fertilizers, especially acidic soil or sandy soil or soil is too viscous, are susceptible to calcium deficiency

Points for prevention and control: ① according to the soil acidity, application of lime 800 ~ 150 kg/mu, and neutralize the acidity of the soil as far as possible, deep application, so that it is distributed to the plant. Deep application, so that it is distributed in the root layer of the plant to facilitate absorption. ② Spraying 0.3% calcium chloride aqueous solution, or 2% calcium superphosphate leaching solution, once every 5 to 7 days, sprayed 2 to 3 times

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