Please ask an experienced fruit grower or agronomist to help me look at my mango saplings.

There must be a potassium deficiency. . . Try to apply some potassium dihydrogen phosphate, the concentration is not too large, just 0.2-0.3%.

One manifestation of potassium deficiency is called "leaf scorch disease", which mostly occurs in young leaves at seedling stage and under three years old, starting from old leaves.

You can refer to the following information:

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