Key Management Techniques for Tomato During the Fruit-setting Stage in Greenhouses

1. Prevent viral diseases. Install insect-proof nets at the ventilation openings, hang yellow sticky boards inside the greenhouse to control whiteflies and other pests, and spray Albit and pyrimethanil or ningnanmycin plus zinc fertilizer on the leaves.

2. Fertilizer and water management. Try to control fertilization and watering before the first truss sets fruit; during this period, focus on promoting root growth and cultivating strong plants. Water and fertilize when the first truss fruit is the size of an egg, and then topdress fertilizer promptly each time a subsequent truss swells. During the fruit-setting stage, the crop needs the most potassium and calcium, so apply high-potassium compound fertilizer twice and calcium nitrate once. Choose full-nutrition water-soluble fertilizers for chemical fertilizers, such as Yara Kristalon from Norway, and combine with chitin-based root-nourishing fertilizers applied through irrigation, such as Shell Power, or Taiwan Wei Dan nutrient solution.

3. Prevent fruit cracking and blossom-end rot. Regularly spray calcium-boron foliar fertilizer on the leaves to prevent fruit cracking and blossom-end rot.

4. Preserve flowers and fruit: spray Albit on the leaves before flowering so the flowers bloom uniformly and large. For flower dipping, generally use Tomatotone, Guoshuling, or 4-CPA; the concentration should be 20-25 ppm in winter and 15-20 ppm in summer. The concentration must be adjusted in time according to temperature; too high a concentration will affect fruit growth. To prevent fruit from failing to set under low temperatures in winter, if the third or fourth truss shows empty trusses, Albit can be added to the flower-dipping solution to increase the fruit-setting rate, with one bag added to 4 jin of flower-dipping solution. It is recommended to use bumblebee pollination, which gives a high fruit-setting rate, good fruit shape, and good taste.