What Pesticide to Spray for Effective Prevention and Control of Grape Berry Cracking
Grapes have a wide range of uses; they can be eaten directly, made into raisins, or brewed into wine, and they can bring good economic benefits. However, quite a few farming friends have reported that grapes are prone to berry cracking during cultivation. So, what pesticide should be sprayed for grape berry cracking?
1. What pesticide to spray for grape berry cracking?
If grape berry cracking is caused by pests or diseases, then spraying is needed. You can use Jinbaike medicinal fertilizer diluted with water at 200-300 times, 50% carbendazim wettable powder at 800-1000 times, or thiophanate-methyl at 1000-1200 times for spray control.
2. Grape Cultivation Techniques
1. Seedling selection
It is best to buy seedlings from after autumn to before the Spring Festival. If the seedlings are not planted immediately after purchase, choose weather above zero degrees, bury the seedlings in bundles flat in a pit 60-80 cm deep, cover with 30 cm of soil so it is slightly higher than the ground, cover the top with a pile of grass, do not irrigate, only sprinkle water, and store below 7°C.
2. Orchard establishment
The orchard site should be chosen on high, sunny land with fertile, deep sandy loam or loose soil and good irrigation and drainage; it can be planted on riverbank land or hilly sandy land. However, for high yield, the soil depth must be more than 60 cm and the organic matter more than 2%. Spread fermented manure on the ground, then deep-plow the soil; then level the land and form ridges, with rows running north-south, row spacing 1.8-2 m, and ridges formed along the rows; build drainage ditches well to ensure no water accumulates after rain. Supports should be set up; the supports can be concrete posts, stone posts, wooden posts, etc. A single trellis is generally used, with the trellis surface perpendicular to the ground.
3. Planting
It is better to plant immediately after the soil thaws, planting at a spacing of 0.7 m between plants. If they are grafted seedlings, plant them slanting toward the north; after planting, water heavily, and when the surface begins to dry, continue mounding soil up to 10 cm above the graft union; after sprouting, remove the soil mound. If they are cuttings, plant them slanting toward the north; after planting, water heavily, and when the surface begins to dry, continue mounding soil. After planting, cover with wet grass, and cover the grass with plastic film to maintain humidity and raise soil temperature.
4. Planting management
(1) Temperature: The minimum air temperature required for grape growth is about 12°C-15°C, the minimum soil temperature is about 10°C-13°C, the optimum temperature during the flowering period is about 20°C, and the optimum temperature during the fruit enlargement period is 20°C-30°C. During the fruiting period, if the temperature difference between day and night is large, coloring and sugar content are better.
(2) Light: During normal growth, grapes must have a certain intensity of light, but it must not be too strong; otherwise, bagging should be adopted, or grape leaves should be used to shade the fruit.
(3) Water: Grapes have relatively high water requirements. In the early growth stage or vegetative growth stage, they need more water; in the late growth stage or fruiting stage, the roots are weaker and need less water. Pay attention to drainage on rainy days, because grapes “are drought-resistant but not waterlogging-resistant.”
(4) Fertilization: The principle of grape fertilization is to grasp the principles of “less first, then more” and “smaller meals, more frequently.” Before the end of June, mainly apply nitrogen fertilizer, 2 times; in July—August, mainly apply compound fertilizer, 2 times; in September—October, mainly apply organic fertilizer, 3-5 times.
(5) Pruning: To improve fruit set rate and berry quality, thin flowers, thin fruit, thin branches, and pinch the tips. At the same time, remove tendrils in time to prevent nutrient consumption and rampant climbing, and also tie new shoots to the wire in time, striving for even distribution.
(6) Pest and disease control: The main grape diseases include black pox, white rot, and downy mildew, and the insect pests include clearwing moths, star caterpillars, tiger longhorn beetles, leafhoppers, red spider mites, etc. Attention should be paid to their control.
For the phenomenon of grape berry cracking, it is necessary to first identify the cause and then treat it accordingly. If it is not caused by pests or diseases, then spraying is not needed.