The malformed fruits of grafted watermelon include malformed fruits caused by poor ovary development, uneven pollination and poor fertilization, flat fruits caused by low-node fruit setting, narrow-shouldered fruits caused by high-node fruit setting, gourd-shaped fruits caused by drought, and plastic fruits caused by melon-shaped correction in the later stage.

Preventive measures include:

1, in the process of female flower differentiation and development, to ensure good light transmission and appropriate fertilizer and water.

2. Artificial pollination makes the pollen adhere to the stigma evenly, without extreme high and low temperature management, and the temperature is kept above 20℃ during pollination, which improves the pollen activity and promotes fertilization.

3. The best fruit setting is in the third female flower, and the fruit setting is controlled in the low node and the high node.

4. Correct the fruit shape in time, at least 1-2 times during the fruit development.

5. Late-harvested fruits are easy to shoulder width and should be harvested as soon as possible.