In the south, how can we let melon farmers grow good watermelons?

1. Watermelon continuous cropping is easy to wilt, and it needs to be rotated for 5~7 years. Because melon seedlings are not easy to move, the method of grafting and changing roots can be used to prevent Fusarium wilt.

2. The suitable rootstocks of watermelon in greenhouse are gourd and pumpkin. Watermelon farmers generally use self-propagating pumpkins and gourds as rootstocks, which have poor disease resistance. However, the new pumpkin (F) has the advantages of low (high) temperature tolerance, strong fertility absorption and stable affinity. The second is to cultivate rootstocks and scions. Rootstock seeds were soaked in warm water at 30℃ for 8~ 10 hour, then wrapped with wet cloth and germinated at 25~28℃. When the seeds are white, they are planted in hotbeds. Generally, seedlings are raised in seedling pots of 10 cm x 10 cm. The seeds are watered first, and then put into each pot of 65438+. After sowing, cover the plastic film with a small arch shed, remove the plastic film after emergence, and the first true leaf of the rootstock is in a suitable grafting period. Watermelon seeds are treated, soaked in warm water for 8- 10 hour, taken out, wrapped with wet gauze, germinated at 28-30℃, germinated two days later, and seeded on the seedbed after germination. After sowing, keep it at 25~30℃ during the day and 20℃ at night. Generally, seedlings emerge in about 5 days, and cotyledons are usually grafted. In order to match the grafting time of rootstock and scion, the rootstock can be planted two days in advance, and after the rootstock is covered with soil, the scion seeds of buds can be sown.

3. Soak the rootstock seeds in warm water at 30℃ for 8~ 10 hour, take them out and wrap them with wet cloth, and accelerate germination at 25~28℃. When the seeds turn white, sow them in a hotbed. Generally, seedlings are raised in 10 cm x 10 cm seedling pots, and the seeds are watered before being put into each pot. After sowing, cover the plastic film with a small arch shed, remove the plastic film after emergence, and the first true leaf of the rootstock is in a suitable grafting period. Watermelon seeds are treated, soaked in warm water for 8- 10 hour, taken out, wrapped with wet gauze, germinated at 28-30℃, germinated two days later, and seeded on the seedbed after germination. After sowing, keep it at 25~30℃ during the day and 20℃ at night. Generally, seedlings emerge in about 5 days, and cotyledons are usually grafted. In order to match the grafting time of rootstock and scion, the rootstock can be planted two days in advance, and after the rootstock is covered with soil, the scion seeds of buds can be sown.

4. Prepare blades and clips and operate them in the greenhouse. First pull out the scion seedlings and wash them. Then, the heart leaves of the rootstock are obliquely cut with a blade, leaving only one cotyledon, which is cut 0.5 cm below the cotyledon of watermelon, cut into inclined planes and connected with the rootstock. Then clamp it firmly, fill the seedling pot with water, put it in a small heat preservation shed, and use 50% carbendazim 1: 8000. When the temperature exceeds 28℃, cover with grass curtain to prevent high temperature from damaging seedlings. Fourth, do a good job in post-grafting management. In the first 6 days after grafting, the greenhouse and the arch shed are closed, and the light is only seen in the morning and evening, so as to achieve appropriate temperature and moisture retention, promote wound healing, and gradually extend the light-seeing time with the growth; The daytime temperature is 25~30℃, and it is not lower than 17℃ at night. When it is higher than 28℃ during the day, use a straw curtain to shade the sun. After the heart leaves grow out, gradually ventilate and harden the seedlings and turn to general seedling management. The lateral buds of rootstocks should be removed in time when they germinate, so as not to affect the growth of watermelon scions.