Kyoho grapes crack at maturity. How to avoid this situation?

Kyoho grape fruit cracking usually occurs in the harvest season. Kyoho grape fruit has poor swelling resistance and is sensitive to ethylene, but the ethylene content is high when the fruit is close to maturity, and it is easy to form cracked fruit. Fruit is easy to crack when it is dry and rainy in the early stage of growth, and it is rainy or even rainy when it is mature, so it dries quickly at high temperature after such weather; The tree is weak, but the amount of fruit left is large and the fruit is too tight, which is easy to cause serious fruit drop; Apply more nitrogen fertilizer; Grapes on red soil are prone to waterlogging and drought, and the rapid change of external environment is easy to lead to fruit drop; Following the traditional pruning method, removing the core leads to less leaves, which reduces the ability of trees to adjust water and is easy to crack in rain; The application of ethephon can accelerate the ripening of cracked fruit, especially in the early stage of extensive use.

Preventive measures for fruit cracking In the early and middle stages of fruit growth, pay more attention to water spraying or irrigation, so that the cell wall and lenticels of the secondary epidermis of fruit stalks are obviously developed, which can increase the critical expansion pressure that causes fruit cracking; Spraying 15 mg/kg of caiacetic acid and 100 mg/kg of abscisic acid on the ear and its leaves can increase the pressure of fruit expansion, make the fruit expand and prolong the life of leaves. Try not to use or postpone the application of ethephon in the late growth stage. Covering vineyards with plastic film can prevent excessive rainwater from accumulating in roots, inhibit the evaporation of surface water and reduce the change of soil moisture. In drought, the combination of plastic film and irrigation can effectively prevent grape from cracking. If the fruit yield of Kyoho grape is too large, it will cause color difference and more fruit cracking, so we should pay attention to adjusting the fruit yield, because trees will increase yield and reduce fruit cracking.

Appropriate amount of nitrogen fertilizer, phosphorus and potassium fertilizer and more bio-organic fertilizer should be applied. Sugar alcohol and calcium fertilizer should be added to heavy soil, and calcium absorption should be ensured by foliar spray washing. Change the traditional coring method and leave more leaves. Leave two leaves on the secondary branch on the ear to remove the core, and all the winter buds and summer buds between the leaf axils of the secondary branch will be removed. Each fruit branch has at most 25-26 normal leaves, which enhances the function of regulating the water content of trees. Orchard cover and timely drainage: when the fruit is about to mature, it should be covered with grass or plastic film to keep water and moisture, watered regularly in dry weather and removed in time in case of heavy rain. When the fruit is ripe, the soil water content should be kept at 65%-75%, so that the root system can absorb water evenly. Irrigation should use several methods to prevent floods. Dig deep to improve soil: poor soil permeability, especially cohesive soil, poor drainage and soil prone to waterlogging and drought, is easy to cause Kyoho grape to crack.

Deep tillage and application of organic fertilizer can effectively improve the existing soil conditions. A trench 60 cm wide and 60-80 cm deep will be dug. Try to avoid damaging the roots when digging ditches. Apply 4000-5000 kilograms of high-quality organic fertilizer every 667 square meters, then mix the soil and fertilizer, backfill and add water. This improves the ventilation of the soil. When the load is too heavy, the fruits squeeze each other. Due to the pursuit of high yield of grapes, the ear shaping density is not in place, the ear is large and there are many fruits, which often causes the fruits to be arranged too tightly and squeeze each other due to lack of space, which leads to the deformation and cracking of some fruits. Moreover, if there are too many fruits, the content of soluble solids in the fruits is low, the flesh is crisp, the peel is thin, the toughness is low, and the coloring is not good, which is also easy to cause fruit cracking. We must control the load reasonably.