Why do persimmon trees drop fruit?

Why do persimmon trees drop fruit? How to prevent and cure it? Please introduce that there are two reasons for persimmon fruit drop, one is the physiological fruit drop caused by the physiological imbalance of the persimmon tree itself, and the other is the fruit drop caused by diseases and insect pests. Whatever the reason, it may cause serious economic losses in a few years. 1. The cause of physiological fruit drop: 1. Malnutrition, during the period of nutrient imbalance, new shoots continue to grow, and nutrients are consumed by new shoot growth, which promotes fruit drop. Flower bud differentiation is not complete, resulting in early fruit drop. 2. Some varieties with poor pollination do not need pollination, such as large grinding plate, and the varieties with this characteristic are not easy to drop fruit physiologically. However, some varieties, especially most sweet persimmon varieties in Japan, must be equipped with pollination trees, otherwise the fruit can not develop and the early fruit drop is serious. In the case of continuous overcast and rain during flowering, it is easy to drop fruit when pollination is affected. 3. Unreasonable tree structure: tall trees, dense branches, poor ventilation and light transmission, which affect the accumulation of organic nutrients in branches, resulting in weak growth of trees, so that the fruits on branches are easy to fall off. 4. the soil is dry for a long time, the soil is barren, and it is difficult to absorb fertilizer and water, resulting in a lot of fruit drop; when the soil moisture is too much, the absorption capacity of the root decreases, even if more fertilizer is applied, the tree is difficult to absorb and use, and the fruit will fall due to the lack of nutrient supply. 5. The effect of rainfall on fruit drop in the early stage of persimmon is related to rainfall. This is due to the lack of sunshine due to rainfall and the weakening of photosynthesis, so that some of the fruits in the nutritionally disadvantageous parts do not get enough nutrients and fall off. 2. Fruit drop caused by diseases and insect pests. 1. Persimmon stalk insect is a kind of pest that specifically harms persimmon fruit, which generally causes persimmon fruit decay before and after wheat harvest, resulting in persimmon fruit softening and shedding, affecting the yield of fruit farmers. 2. The damage of persimmon scale insects is also called tree lice, which is very harmful to persimmon trees and often causes serious fruit drop. 3. Anthrax generally occurs in large numbers in September, causing fruit drop. Third, countermeasures to prevent persimmon from falling fruit 1. Strengthen fertilizer and water management to maintain healthy growth and enhance the assimilation ability of leaves, so as to regulate the distribution of nutrients within branches and ease the contradiction between growth and fruit competition for nutrients. 2. Proper pruning, especially strengthening summer pruning, removing useless and superfluous branches, promoting ventilation and light transmission, ensuring adequate light conditions, timely elimination of stagnant water in the rainy season, timely irrigation in the dry season, keeping the tree potential growing vigorously and the fruit developing well. 3. Most varieties of persimmon trees with suitable mixed pollination have only female flowers, although there are only a few varieties with male flowers, after all, there are only a few. In order to make effective use of the male flowers of these pollination trees, artificial pollination is suitable for artificial pollination. Due to different environment and climate, persimmon flowers bloom first and later, so artificial pollination should be carried out for 3 times and 4 times, so pollination can be reliable and can effectively prevent physiological fruit drop. 4. Girdling at flowering stage can not only promote flower bud differentiation and early fruiting, but also reduce physiological fruit drop and advance fruit maturity. The suitable period of ring peeling is generally carried out at half of the flowering time of persimmon trees, and if the period is too late or the peeling width is too large, it is difficult for the wound to heal, resulting in the weakness of the tree, or even the death of the whole branch or the whole plant. The peeling width is limited to 1.5 cm and the depth is up to the cambium. Although peeling has many advantages, it should not be carried out every year, otherwise it is easy to weaken the tree and shorten its life. In addition, strengthen the supply of fertilizer and water after girdling. 5. For the prevention and control of diseases and insect pests to anthracnose, spray 4-Mel-5-Baume-sulfur mixture before germination, and spray Bordeaux solution once in the first and middle of June and the first and middle of August. The persimmon stalks were scraped in winter, and the persimmon stalks left on the trees were removed and destroyed centrally. The harmful fruits of larvae should be removed timely and thoroughly in mid-late June and mid-late August, and those that have fallen should be picked up and buried deeply together, so as to reduce the harm of the next generation or the second year. Persimmon flower bud sprouting period with 48% Lexben 1000 Mel 1500 times solution, 10 days after flowering with 1.8% avermectin 4000 Mel 5000 times, can effectively control shell insects and improve fruit setting rate. 6. Applying regulator and foliar fertilizer spraying gibberellin with 500ppm at flowering or young fruit stage, spraying alone or adding 1% urea is effective in preventing fruit drop. Click to get more persimmon planting techniques click to get more fruit planting techniques