What temperature is suitable for planting apple trees?

What temperature is suitable for planting apple trees? What kind of temperature do apple trees need in what season? Netizens who have experience in apple tree planting are also invited to help introduce the various physiological activities, biochemical reactions, growth and development of apple trees, which can only be carried out under certain temperature conditions. Otherwise, its normal growth and development will be inhibited, hindered, victimized or even died. Therefore, the farming network has sorted out the temperature requirements of apple trees, which are listed in detail below for netizens' reference. 1. The lowest, most suitable and highest temperature for the growth of apple trees: the temperature needed for the life activities and growth and development of apples, as far as its physiological process is concerned, has the corresponding lowest, most suitable and highest three basis points of temperature. It is generally believed that the lowest temperature of apple is about 5.0℃, the optimum temperature is 13-25 ℃, and the highest temperature is about 40 ℃, which varies with variety, organ, age, growth period, physiological process and temperature, as well as other ecological factors. The optimum average temperature during the growing period of different varieties was also different. Second, the introduction of accumulated temperature of apple trees: different apple varieties, different organs and growth periods all require a certain amount of accumulated temperature. The accumulated temperature has an important effect on the growth, development, yield and quality of apple. Therefore, accumulated temperature is often used as an important index of variety characteristics, and it is an important basis for phenological prediction, yield and quality research, ecological analysis and regionalization. Third, the function of apple tree accumulated temperature: the apple flowering period can be predicted by calculating the apple pre-flowering accumulated temperature. In temperate regions, the effective accumulated temperature of 5 ℃, the lowest temperature for tree growth, is generally used to predict flowering stage. According to the research, the average effective accumulated temperature higher than 5 ℃ is 160-180 ℃ from the temperature of 5 ℃ to the first flowering stage, and there is little change among varieties. However, the length of reaching the flowering stage is affected by the air temperature. Most varieties need to experience about 50 days at the daily average temperature of 7-8 ℃, 40 days at 10 ℃ and only 30 days at 12-13 ℃. The effective accumulated temperature from the beginning of growth to flowering of most apple varieties is 185 ±10 ℃, and some years differ as much as 101 ℃. According to relevant reports, the effective accumulated temperature from growth to flowering of Guoguang apple in Xingcheng, Liaoning Province was about 155.2 ℃ in 1954 and 253.113 in 1955, with a difference of 79.9 ℃. The above results show that the prediction of flowering stage with effective accumulated temperature of more than 5 ℃ before flowering is not accurate, and the accumulated temperature required by different varieties or the same variety is different in different regions and years, and also affected by different topography and microclimate. Fourth, the temperature of apple tree flowering: if an apple wants to blossom, it needs to reach a certain amount of accumulated temperature first. Apple is sensitive to temperature during flowering. Temperature is an important limiting ecological factor for the successful completion of flowering, pollination, fertilization and fruit setting. The optimum temperature for apple flowering is 11.4-11.8 ℃, and the optimum temperature is 17-18 ℃. From the point of view of the temperature needed for the activity of the pollinator honeybee, the honeybee generally stops going out under 10 ℃, and gradually becomes active with the increase of temperature between 15 and 29 ℃, which is beneficial to pollination and pollination. The temperature at flowering stage is an important condition for apple pollen germination and pollen tube elongation to complete fertilization. It was observed that different varieties required different suitable temperature, the suitable temperature for pollen germination was generally between 10 and 25 ℃, and the optimum temperature was 15 to 20 ℃. When the temperature was higher than 30 ℃, pollen germination was obviously inhibited. Fifth, the effect of low temperature on apple trees in spring: most of the apple producing areas in China belong to continental monsoon climate, the temperature is unstable in spring, and low temperature often occurs, especially the harm of late frost. Apple is in the period of budding, flowering and fruit setting in spring, with weak tolerance to low temperature and sensitive to temperature. The temperature in spring is closely related to the shape and appearance quality of apple. According to the study, when the temperature is low and the climate is cold 15-16 days after flowering, the fruit longitudinal axis grows faster than the horizontal axis, and the fruit shape index is larger. On the contrary, the fruit shape index is small. This is related to the post-anthesis division of fruit cells and endogenous hormones in this period. Sixth, the effect of summer and autumn temperature on apple trees: because summer and autumn coincide with the period when apple shoots stop growing, flower bud differentiation, fruit development and maturity, therefore, summer and autumn temperature has a great influence on flower bud differentiation, yield formation and quality. The investigation shows that the temperature is too high or too low in summer and autumn (June-September), which is disadvantageous to the above-mentioned growth process of apple, and the most suitable range of monthly mean temperature is between 16.5 and 22.85 ℃. For example, in the national evaluation, the monthly mean temperature in Maoxian County, Sichuan Province, Xiaojin County, Sichuan Province, and Tianshui in Gansu Province, where the fruit quality of Marshal and Jinguan were among the best for many times, varied from 16.2 to 22.7 ℃ in summer, while that in Tongchuan in Shaanxi Province was the highest, with a monthly average temperature of 23.5 ℃ in summer. If the summer temperature is too high, the ecological reaction is that the fruit shape index becomes smaller, the color is poor, the pulp is easy to sponge, the ripening consistency is poor, the vitamin content is decreased, and the aroma, flavor and storability of the fruit are poor. Summer temperature and flower bud differentiation: it is pointed out that the suitable temperature at the beginning and peak stage of apple flower bud differentiation is 20-27 ℃. The morphological differentiation period of flower buds of Marshal and Guoguang began after a certain number of days when the average temperature was more than 20 ℃. 7. The effect of low temperature on apple trees in winter: it is generally believed that the induction of apple into true dormancy is mainly due to the effect of low temperature and is not sensitive to conditions such as short-day light and drying. In order to end the true dormancy of buds, many studies believe that the cool climate in winter is also necessary. Cold temperature hours: that is, the number of hours that experienced a low temperature below 7.2℃. The starting point for cold temperature is 7.2 ℃. At present, most scholars in various countries take 7.2℃ as the cumulative time standard. Apples need CH values, which vary greatly from variety to variety. With the expansion of modern cultivation areas to low latitudes, the number of CH required for apples tends to decrease gradually. From 1400-3684 ℃ in the early stage to 500-1700 ℃ in the near future. 12 pruning methods of Apple trees fertilization methods of Apple trees