Reason:

(1) The temperature is not suitable. Generally speaking, the suitable temperature of sweet persimmon in autumn is between 65438 03℃ and 65438 08℃ every year. For example, when it is cultivated early in high temperature areas, the coloring is delayed, and green spots often appear on the fruit surface. If planted in high altitude areas in the north or south, 90% of persimmon fruits will not be astringent. Therefore, we must be careful when introducing these varieties. ?

(2) Pollination encountered problems. Most varieties of Daqiu sweet persimmon have no male flowers, so it is impossible to pollinate themselves. Parthenogenesis or parthenogenesis. However, the parthenocarpy ability varies greatly among different varieties. Some people say that this is not a problem. I can plant pollination trees. This is ok in the north, but there is a problem in the south. Because the flowering and pollination season of persimmons in the south is just when the spring rain is continuous and the air is humid, even if pollination trees are planted, they can't pollinate. We must be cautious in developing in the south, especially for new growers who lack artificial pollination technology. ?

(3) Party consolidation. At present, in order to reduce the cost, more than 95% of the nursery farms use Junqianzi to graft sweet persimmon. But not everyone can use the Qian Jun.

(4) the problem of cooling capacity. There is an important concept in fruit tree cultivation called "chilling requirement", which refers to the effective low temperature hours required for deciduous fruit trees to hibernate naturally, usually expressed by the accumulated low temperature hours of 0 ~ 7.2℃ (excluding 0℃) after entering dormancy. If the low temperature is not met, even if the temperature and humidity conditions are suitable for fruit trees to germinate and bloom, they will not germinate normally, which is characterized by dead buds, irregular flowering (long duration) and low fruit setting rate, which further affects the yield. The winter climate in northern China is cold and the low temperature lasts for a long time, while the winter climate in southern China is warm and the low temperature lasts for a short time. Therefore, when choosing sweet persimmon varieties in autumn, we should pay attention to choosing varieties with low chilling requirement. ?