Apple tree management technology is mainly the management of temperature, soil, precipitation, sunshine and other aspects, as follows:
● Soil
Soil has a great influence on the growth, yield and quality of apples. The main factors are soil layer, soil ventilation and soil quality. In short, apples need deep soil, good drainage, rich organic matter, slightly acidic to slightly alkaline.
● Temperature
Apple tree is a temperate fruit tree that likes low temperature and dryness. It requires no cold in winter and no heat in summer. The suitable temperature range is the annual average temperature of 9 ~ 14℃, the extreme low temperature in winter is not lower than-12℃, the highest monthly average temperature in summer is not higher than 20℃, the annual accumulated temperature is ≥ 10℃, and the average temperature in the growing season (April ~ 10) is about 5000℃. It is generally believed that apples can be planted in areas where the annual average temperature is 7.5 ~ 14℃. The natural dormancy period of apples is very long. If the temperature in winter is too high, it can't reach the low temperature needed for winter dormancy, and the germination in spring is uneven. Judging from the areas with the most apples in the world, the average temperature in Leng Yue in winter (65438+ 10 in the northern hemisphere and July in the southern hemisphere) is between-10 ~ 10℃, which can meet the requirements of low temperature for apples. The average temperature of the main apple producing areas in China 1 month is within this range. The average temperature 12 ~ 18℃ in the growing period (4 ~ 65438+ 10 month) and 18 ~ 24℃ in the summer (June ~ August) are the most suitable for apple growth. The summer temperature is too high, the average temperature is above 26℃, and the apple flower bud differentiation is poor. Insufficient heat, poor flower bud differentiation, small and sour fruit, poor color and poor storage resistance. In autumn, the temperature is high during the day and low at night, and the fruit has high sugar content, good coloring, thick peel, more fruit powder and storage resistance.
● Precipitation
The precipitation per mu during the apple growing period is about 180mm. Generally, natural precipitation can actually be absorbed by fruit trees, which is about 1/3, so it is enough to have a precipitation of 540mm during the growing period. Areas with rainfall below 450 mm from April to September need irrigation. The distribution of precipitation in northern China is uneven, with 70-80% concentrated in July and August, and the amount of water is insufficient in spring. There is little precipitation and water shortage in inland areas, so irrigation conditions and soil and water conservation measures must be considered when building gardens and selecting land, and drainage measures should also be paid attention to in rainy season.
● Sunshine
Apple is a light-loving tree, and it can grow normally only when there is enough light. According to the measurement of Shandong Agricultural University, the light compensation point of Jinguan and emerging in Tai 'an area is 600 ~ 800 m candle, and the saturation point is 3500 ~ 4500 m candle. In this range, the light intensity increases and photosynthesis is also strengthened. Insufficient sunshine will cause a series of reactions such as excessive growth of branches and leaves, weakness, poor resistance to pests and diseases, less differentiation of flower buds, less nutrient storage, low flowering and fruit setting rate, affected root growth, low sugar content of fruits, and chromatic aberration.
● Wind
Strong winds often bring many adverse effects to the growth and development of apples, such as causing crown deflection, affecting flowering, pollination, destroying leaf organs, fruit dropping and so on. Therefore, it is necessary to build windbreaks to establish apple orchards in windy areas.
Apple Tree Management Technology: Management of Fruit Development and Quality Formation
Apple fruit is a fake fruit developed from ovary and receptacle, in which ovary develops into heart, receptacle develops into meat and embryo develops into seed. The volume expansion of fruit depends on the increase of the number of rapidly dividing cells in the early stage and the volume expansion of cells in the later stage.
The volume expansion of fruit is faster in the middle period to before ripening, slower in the early and late period, and the fruit weight increases fastest in the month before ripening. The length of fruit development period is generally 65 ~ 87 days for early-maturing varieties, 90 ~ 133 days for middle-maturing varieties and 137 ~ 168 days for late-maturing varieties. Fruit color is an important indicator of commodities. The quality of apple coloring is closely related to the accumulation of sugar, the coordination of mineral elements, environmental conditions, and the types and contents of hormones.
Controlling application of nitrogen fertilizer, increasing application of potassium fertilizer, reducing chlorophyll in peel, improving ventilation and light transmission conditions, improving sunshine, good drainage, reducing air humidity, spraying NAA and 2.4-D hormone can all promote apple coloring.
From the appearance of buds to the harvest of fruits, apples usually have four flowers and fruits. The first time in the final flowering period, the pedicel falls off with withering, which is usually called falling flower. The second time, about a week after flower dropping, the ovary is slightly enlarged and lasts for 5 ~ 20 days, which is called early fruit dropping. 7 ~ 14 days after the third and second fruit drop, the fruit has reached the size of thumb nail, which has a great influence on the yield, so it is called physiological fruit drop. Yunnan usually occurs in May, and the phenology in the north is later than that in Yunnan, which occurs in June, so it is called "June fruit drop".
The fourth time, before the fruit is harvested, the mature or nearly mature fruit is dropped, so it is called pre-harvest fruit drop. The first and second falling flowers and fruits are mainly caused by insufficient nutrition and poor pollination and fertilization. The third fruit drop is caused by the fierce competition for nutrients among fruits and the lack of auxin in embryos. Because the osmotic pressure of leaves is greater than that of young fruits, the power to compete for nutrients is stronger than that of young fruits. Therefore, in addition to pinching and pruning branches to inhibit the growth of new shoots, it is necessary to apply huafei to supplement nutrients in time.