Flat land, mountains, beaches and floodplains can all be planted, but gentle slopes with abundant sunshine, openness, leeward and good surrounding vegetation are the most suitable for planting. Depression, gully, although the soil layer is deep, but the illumination is poor, it is easy to accumulate water in rainy season, and the air humidity is too high; The steep slope, shallow soil layer, thin soil and heavy soil erosion are not conducive to the growth of fruit trees.
Apples are not strict about the soil. Clay, sandy soil and loam can be used, but sandy loam with deep soil layer and loose and fertile soil is the best. Thick soil with shallow soil layer and many gravels must be improved before planting. The adaptive PH range is pH 5.3-8.2, and the optimum pH is 5.4-6.8. If it is lower than 5.4, the acidity is too strong, and it is easy to produce fruit shrinkage and bitter pox due to boron and calcium deficiency; Above 7.8, it is alkaline, and it is easy to lack iron, which leads to the loss of green leaves.
Apple is a temperate fruit tree, which likes cold and dry. It requires that winter is not cold, summer is not cool, and the annual variation is small and the daily variation is large.
Although apple is native to the dry inland climate zone in summer, and prefers dry environment, it still needs sufficient water and suitable air humidity to grow and develop normally during the growing period. However, excessive rainfall and humidity will lead to dense branches and leaves, serious pests and diseases, large color difference of fruits and low acid concentration of sugar. Generally, the annual rainfall is 500- 1000mm and the air humidity is 60%-70%. Because the rainfall in Yunnan is unevenly distributed in time and space, and the dry season is clear, it should be irrigated once a month in the dry season from February to May in order to meet the water needed for budding, flowering and fruiting. Drainage should be done well in rainy season to reduce soil water content and air humidity, so as to reduce the occurrence of pests and diseases and improve fruit quality. Apple is the fruit of Malus in Rosaceae, with about 25 species. Apple tree is the most widely cultivated fruit tree. Apple is a kind of pear fruit, which is developed from ovary and tissues around it. Most apple trees are cross-pollinated, and 2 ~ 4% of apple trees have ideal fruit setting. Although the size, shape, color and acidity of mature apples vary greatly with varieties and environmental conditions, they are usually round, with a diameter of 50 ~ 100 mm (2 ~ 4 inches) and a reddish or yellow color.
There are thousands of varieties of apples, which are divided into three categories: wine varieties, cooking varieties and tail foods. The three varieties are different in color, size, fragrance, smoothness (and possibly crispness and flavor). Many varieties have high sugar content, moderate acidity and low tannin content. Besides raw apples, there are many cooking methods, which are often used as snack fillings. Apple scones may be the earliest sweet-tailed food in America. Fried apples are often eaten with sausages, pork chops and other dishes, especially in Europe.
The genus Malus is native to temperate regions in both hemispheres. The earliest Europeans ate apples and improved their choices. Some varieties were seen more than 2000 years ago. Before colonizing the United States, there were hundreds of known varieties in Europe. Later, with the wave of immigration sweeping across North America, the seedlings of apple varieties also spread everywhere, becoming itinerant messengers of local legends, which played an important role in the spread of apples. The most prominent one was john chapman (nicknamed "〔Johnny Appleseed"), who planted apples widely in Ohio and Indiana. Indians and hunters may also spread apples.
Apple trees need a certain dormancy period and grow well in areas where winter is obvious (generally 30 ~ 60 north latitude). Further north, due to the cold winter and short growing season, planting is restricted. When planting apples, we should choose soil with good drainage and fertilize when the fertility is insufficient. The top of a rolling hill or hillside is best for growing apples. In this terrain, cold and heavy air will flow down into the valley on a cold spring night, otherwise the apple flowers and fresh fruits will be frozen. Take the selected varieties as scions, and the rootstock is usually cold-resistant seedlings1August, and transplant them into orchards 1 ~ 2 years after grafting. After 6 ~ 8 years, there will be considerable output; Prior to this, the management work was mostly limited to weeding and pest control, and pruning was needed (especially in the first five years) to make the distribution of main branches reasonable and the weaker branches would not break under the weight of fruits. Adult fruit trees should be sprayed with pesticides in strict accordance with regulations to prevent pests, which may also delay their vigorous growth in spring, sparse young fruits and reduce fruit drop in autumn. Varieties that mature in late summer are generally not suitable for storage. Varieties that mature in late autumn can be carefully stored for up to one year. It can be stored for a long time at a temperature slightly higher than the freezing point of apples. Apples can also be stored in inert gas or air with controllable composition. First, buds and flowers:
The flower bud differentiation of most apple varieties began in early June and ended before winter. The whole process is divided into three stages: physiological differentiation, morphological differentiation and sexual cell maturation. The flower buds are mixed buds and the inflorescences are corymbose cymes. Each inflorescence has 5-8 flowers, mostly 5. The central flower blooms first, and the marginal flower blooms later. The central flower has the best quality, stable fruit and large fruit. When thinning flowers and fruits, the central flowers and fruits should be kept, and the marginal flowers and fruits should be thinned more. The bud leaves first, then blooms, and shoots from the fruit table. The number and length of branches on the fruit table vary with varieties and nutritional conditions of fruiting mother branches. Varieties with strong secondary branches and long and strong branches, such as Zhuguang, have small fruits, low yield and loose fruiting branches. This variety uses thinning 1, leaving 1 and pinching new shoots to control the growth of secondary branches. Varieties with medium secondary branch growth (1 or 2), short branches (below 10 cm) and thick branches, such as Jin Shuai and Jonakin, have large fruits, high yield, compact fruiting branches, easy regeneration and strong continuous fruiting ability. Varieties with weak secondary shoot growth (1) and short branches (less than 3 cm), such as Yuan Shuai and Enpai, have large fruits, compact fruiting branches, easy to form chicken feet branches and easy to update. However, most fruit forests bear fruit every other year, so more reserve branches should be left to reduce the fruit bearing in different years.
Second, the fruit:
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 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, and it 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. Developed from fertilized eggs in embryo sacs. The normal fruit of apple has five ventricles, and there are two seeds in each ventricle. In the process of fruit development, seeds secrete hormones to stimulate the growth of pulp, so those with good pollination and fertilization, full seeds, correct fruit shape and full pulp; On the other hand, on the side with poor seed development or no seed, the pulp becomes thin and deformed, so pollination trees must be arranged to improve the pollination effect. Temperature: Apple tree is a temperate fruit tree that likes low temperature and dryness, requiring no severe cold in winter and no intense 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℃. Low temperature time is not enough, leaves and flowers are delayed irregularly, and some flower buds don't even germinate. In May, the scales became loose and fell off, which became a dead pile and seriously reduced production. When the absolute low temperature is lower than -30-32℃, freezing injury occurs again. According to the survey, the performance of apples at different altitudes and temperatures in Yunnan Province is as follows.
Show the performance of apples at different altitudes and temperatures in Yunnan.
Suitability of altitude (m), annual average temperature (℃) and growth law of pests and diseases to high-yield fruit quality
The difference weights below 1800 and above 15 are abnormal and inappropriate.
1800-200014-15, the heavier one is less suitable than the normal one.
Nutritional analysis of apple variety "No.9" 2000-2200, 13- 14.