Kiwifruit sunscald disease must be prevented in advance during the high-temperature season
Kiwifruit is particularly sensitive to wind. In summer, the shoots grow very vigorously and are easily broken off by wind from the base, which not only affects the growth and fruiting of the current year but also affects the yield of the following year. At the same time, wind also easily bruises leaves and fruit, making the trees more susceptible to disease and reducing the marketability of the fruit. Strong winds can also cause leaf drop, affecting flowers...
Kiwifruit is most prone to sunburn under high temperatures. Preventing sunscald early is a pressing task. Several methods for preventing sunburn are introduced:I. Summer pruning: Leave 2-3 more leaves above the topmost fruit to block direct sunlight. This is especially necessary for Hayward and Jinyu, which need several more leaves left on;
II. If conditions permit, spray water once every few days in the morning and evening, or apply Guoyou amino acid 400-fold solution, to lower the orchard temperature and quickly supply nutrients;
III. Orchard mulching: Wheat bran or wheat straw can be used as mulch. For example, Zhang Jiangcheng's orchard in Mei County directly mulches between the rows to reduce soil moisture evaporation;
IV. For bagged fruit, open the ventilation holes. If the ventilation holes are small, they can be slightly enlarged by cutting, using ventilation to lower the temperature inside the bag, generally by 1-2 degrees Celsius.
V. For kiwifruit orchards that have not been given fruit-expanding fertilizer, increase potassium fertilizer application or spray calcium lactate foliar fertilizer. Calcium can enhance the toughness of the fruit's outer skin cells and the thickness of cell walls, to resist sunscald or damage.
VI. For fruit exposed to the western sun, hang grass or use newspaper to create shade on the fruit or at the western exposure, reducing direct sunburn of fruit exposed to the western sun.
VII. Irrigate promptly during drought to lower the overall orchard temperature and reduce the occurrence of sunscald disease.