Possibly root-knot nematode, which mainly infests the roots. The diseased part produces fat, swollen, deformed tumor-like knots of different sizes and shapes. Dissecting the root knot with milky white nematodes, more in the upper part of the root knot to produce new roots, reinfestation and then form a root knot tumor. When the disease is light, the symptoms on the ground are not obvious, and when the disease is severe, the plant is short, stunted, the leaves turn yellow, and the results are small. When high temperature and drought, the diseased plant appears to wilt or die in advance. To prevent and control nematodes, you can usually use thiazophos or abamectin to irrigate the roots, you can also kill it by smothering the greenhouse at high temperatures, and use less non-rotted manure in the future

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