(1) Strengthen temperature and humidity management. The pollination and fertilization of grapes need high temperature. When the average temperature of the day was stable at 20℃, Eurasian open-field grapes entered flowering period. The optimum temperature for flowering is 25℃ ~ 30℃, when the pollen germination rate is the highest, and the fertilization process can be completed within a few hours. When the temperature is higher than 35℃, flowering is inhibited. According to the experiment, the pollen germination of Kyoho grape is best at 30℃, and pollination is poor below 25℃. Therefore, the daytime temperature of flowering period is controlled at 28℃, not lower than 25℃. The temperature at night should be kept at 16℃ ~ 18℃ and not lower than 10℃.
The air relative humidity is controlled at 50% ~ 65%.
(2) Improving the fruit setting rate. Spraying 0. 1% ~ 0.2% borax water solution before or at the beginning of flowering can improve the flower bud differentiation ability and fruit setting rate of grapes. It is not suitable to fertilize water at flowering stage, and the drastic change of water content is easy to cause falling flowers and fruits.
(3) Under the cultivation condition of a certain load in the protected field, 4-5 ears of fruit should be reserved per square meter of effective shelf surface, and the yield of 667 square meters (mu) should be controlled at 2000-2500 kg.