Why do persimmon trees drop fruit?

Persimmon is a kind of fruit that people like very much. It can give birth to fluid, clear away heat, strengthen spleen and stomach. But persimmon in the growth process, there may be the phenomenon of falling flowers and fruits. Why do persimmon trees drop fruit? In fact, there are two main reasons, one is the physiological fruit drop caused by the physiological imbalance of persimmon itself, and the other is the fruit drop caused by diseases and insect pests such as anthracnose or persimmon stalks.

1. Physiological fruit drop of persimmon

The degree of physiological fruit drop of persimmon varies greatly among varieties. For example, the fruit drop of Damopan persimmon, the main variety in Taihang mountain area of our province, is relatively light, which is generally less than 10%, which is not easy to detect, while the fruit drop of Dahongpao variety is serious after entering the full fruiting period. at most, the fruit drop rate reached 2x3.

The degree of physiological fruit drop is related to the fruit position. On the same tree, there are less fruit drop in the outer and upper part of the crown, while more fruit drop in the lower part and inner chamber, which is related to the different degree of light exposure in different parts of the crown. Therefore, the fruiting branch or fruiting mother branch is located at the top, the growth is strong, the fruit drop is less, on the contrary, if the fruit branch is located in the lower part or the branch is thin, the fruit drop is heavy.

On the same fruiting branch, the fruit falling in the middle is the lightest, the top is the second, and the base is the heaviest. This is related to the degree of flower bud differentiation of branches, the flower bud differentiation in the middle part is earlier, the differentiation speed is faster, and the fruit is light.

Most of the physiological fruit drop occurs from the flower drop to the middle of July, and the fruit drop is the most serious before and after the wheat harvest, accounting for about 80% of the total fruit drop in the whole year, and some varieties still have a fruit drop from August to September.

2. Fruit drop caused by diseases and insect pests

First, persimmon stalk insects do serious damage. Persimmon stalk insects are generally harmful to the fruit before and after the wheat harvest. The first generation of damaged fruit is not easy to fall off and will hang on the tree all the time, in which the larvae pupate and continue to harm the second generation. The second generation of persimmon fruit, the color from yellowish green to orange-red, from hard to soft easy to fall off. Second, anthrax. Occur in the late growth, generally in September a large number of disease, resulting in fruit drop.

To prevent persimmon from falling fruit, first, it is necessary to configure pollination tree varieties, pollination trees must be planted or artificial pollination must be carried out. The second is to ring-cut the trunk or branches of the strong tree during the flowering period, with a width of no more than 0.5 cm. For safety reasons, it is best to leave seat belts or spiral ring cuts to facilitate healing. In addition, the supply of fertilizer and water should be strengthened after ring cutting. Third, appropriate pruning, especially to strengthen summer pruning, remove useless and redundant branches, promote ventilation and light transmission. Fourth, prevent and control diseases and insect pests, strengthen the management of fertilizer and water, and enhance the tree potential. Fifth, spraying gibberellin with 500ppm at flowering or young fruit stage, spraying alone or adding 1% urea has a good effect on preventing fruit drop.

To prevent persimmon from falling flowers and fruits, it is necessary to do a good job in pruning, fertilizer and water management and pest prevention, so that persimmon can have a good growth environment in order to produce large and sweet fruit.