Instructions for growing red apples

Apple is a light-loving fruit tree. According to measurements, the light compensation point of most varieties is 600-940 lux, and the saturation point is 24000-75000 lux. Insufficient light directly reduces photosynthesis and tree nutrition levels, and affects fruit coloring and sugar conversion; too much strong direct light and too long exposure time can easily cause branches and fruits to be burned. Therefore, it is necessary to select a good garden site and perform pruning, improve ventilation and light transmission, and have a reasonable leaf curtain layer to avoid the aforementioned disadvantages.

It can be planted on flat land, mountains, beaches, and river flats, but it is best to plant in sunny, open, leeward, gently sloping land with good surrounding vegetation, good light, and convenient irrigation and drainage; depressions and ridges are the best. Although the soil layer is deep in ditches, the light is poor, water easily accumulates in the rainy season, and the air humidity is too high; on steep slopes, the soil layer is shallow, the soil is thin, and soil erosion is heavy, all of which are not conducive to the growth of fruit trees.

Apples do not have strict soil requirements. Clay, sandy soil, and loam are all acceptable, but sandy loam with deep soil, loose and fertile soil is best. Heavy clay soil with shallow soil layer and excessive gravel must be improved before planting. The range of adaptable pH value is 5.3-8.2, and the optimum range is 5.4-6.8. If it is lower than 5.4, it is too acidic, and it is prone to fruit shrinkage and bitter pox disease caused by boron and calcium deficiency; if it is higher than 7.8, it is too alkaline, and it is prone to iron deficiency, causing leaf chlorosis.

Apple is a temperate fruit tree that likes coolness and dryness. It requires no severe cold in winter and no severe heat in summer, with small annual range and large daily range.

Although apples are native to inland climate areas with dry summers and prefer a drier environment, they still need sufficient water and suitable air humidity during the growth period for normal growth and development; however, excessive rainfall and humidity If it is too large, it will lead to dense branches and leaves, serious diseases and insect pests, poor color of the fruits, low sugar and high acidity. Generally, annual rainfall is 500-1000 mm and air humidity is 60%-70%. Since the spatial and temporal distribution of rain in Yunnan is uneven and the dry and rainy seasons are distinct, in the dry season from February to May, top dressing should be combined with irrigation once a month to meet the water requirements for leaf growth and flowering and fruiting; drainage must be done well during the rainy season. Reduce soil moisture content and air humidity to reduce the occurrence of diseases and insect pests and improve fruit quality. Apple is the fruit of the genus malus in the Rosaceae family. There are about 25 species in this genus. The apple tree is the most widely cultivated fruit tree. Apple is a type of pome fruit, which develops from the ovary and the tissues surrounding the ovary. Most apple trees are cross-pollinated, and it is ideal for 2 to 4% of the flowers to bear fruit. Although the size, shape, color, and acidity of ripe apples vary greatly depending on the variety and environmental conditions, they are generally round, 50 to 100 mm (2 to 4 inches) in diameter, and reddish or yellowish.

There are thousands of apple varieties, divided into three categories: wine varieties, cooking varieties, and snack varieties. The three types of varieties differ in color, size, aroma, smoothness (and possibly crispness, flavor) and other characteristics. Many varieties have high sugar content, moderate acidity, and low tannin content. In addition to being eaten raw, apples can also be cooked in many ways. They are often used as snack fillings. Apple-filled scones may be the earliest American sweet snack. Fried apples are often served with sausages, pork chops and other dishes, especially in Europe.

The genus Malus is native to the temperate zones of both hemispheres. The earliest Europeans had eaten apples and improved and bred them. Some varieties appeared more than 2,000 years ago. Before colonizing the Americas, there were hundreds of known varieties in Europe. Later, as waves of immigrants flooded across North America, seedling apple varieties spread everywhere and became roving emissaries of local legends, playing a major role in the spread of apples. The most prominent of them was John Chapman, nicknamed " Johnny Appleseed), who grew apples extensively in Ohio and Indiana. Indians and trappers may have also spread the apple.

Apple trees require a certain period of dormancy and grow well in areas with obvious winter (generally between 30° and 60° south and north latitudes). Further north, cultivation is limited due to too cold winters and short growing season. To grow apples, you need to choose well-drained soil, and fertilize when the fertility is insufficient. The tops of undulating hills or hillsides are most suitable for growing apples. In this kind of terrain, the colder and heavier air will flow downward into the valleys on cold spring nights, otherwise the apple flowers and tender fruits will be frozen. The selected variety is used as the scion, and the rootstock is usually a cold-resistant nursery seedling that is about 18 months old. It is transplanted into the orchard 1 to 2 years after grafting.

There will be considerable yields after 6 to 8 years; before that, management work is mostly limited to weeding and insect removal, and branches must be pruned (especially in the first 5 years) so that the main branches are distributed reasonably and the weaker branches will not Broken under the weight of the fruit. Adult fruit trees must be sprayed with pesticides in strict accordance with regulations to prevent and control pests. Doing so may also delay their spring growth, thin out 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 stored for up to a year with careful care. Apples can be stored for longer periods of time at temperatures slightly above their freezing point. Apples can also be stored in inert gas or air with controlled composition. 1. Flower buds and flowers:

The flower bud differentiation of apples begins in early June and is completed before winter in most varieties. The entire process is divided into three stages: physiological differentiation, morphological differentiation and sex cell maturation. The flower buds are mixed buds and the inflorescences are corymbose cymes. Each inflorescence blooms 5-8 flowers, mostly 5 flowers. The central flower blooms first, and the side flowers bloom later. The central flower has the best quality, stable fruit setting, and large results. When thinning flowers and fruits, the central flower and central fruit should be retained. , many sparse edge flowers and edge flowers and fruits. Flower buds first produce leaves and then bloom, and produce secondary shoots from the fruit stand. The number and length of secondary shoots from the fruit stand vary with the variety and the nutritional conditions of the fruiting mother branch. Varieties with strong (two) secondary shoots and long and strong branches, such as Zhuguang, have small fruits, low yields, and loose branch clusters. For this type of species, methods such as thinning one and leaving one and pinching and twisting should be used to control the growth of secondary shoots. Varieties with medium secondary shoot growth (1 or 2), short and thick branches (less than 10 cm), such as Jinshuai, Jonagold, etc., have large fruits, high yields, compact branch groups, easy renewal, and continuous fruiting ability powerful. Varieties with weak secondary shoot growth (1) and short branches (less than 3 cm), such as Marshal series, Entai, etc., have large fruits and compact branch groups, which are easy to form chicken-foot branch groups. They are easy to renew, but have many fruit sets. In order to bear fruit every other year, more preparation branches should be left to reduce the number of bears in the next year.

2. Fruit:

Apple fruit is a false fruit that develops from an ovary and a receptacle. The ovary develops into a fruit core, the receptacle develops into a pulp, and the embryo develops into a seed. The expansion of fruit volume depends on the increase in the number of rapidly dividing cells in the early stage and the expansion of cell volume in the later stage.

The expansion of fruit size is faster from the middle stage to before maturity, and slower in the early and late stages. Fruit weight increases fastest in the month before maturity. The length of fruit development period is generally 65-87 days for early-maturing varieties, 90-133 days for mid-maturing varieties, and 137-168 days for late-maturing varieties.

Fruit color is an important indicator of the product. The quality of apple coloring is closely related to the accumulation of sugar, coordination of mineral elements, environmental conditions, and hormone types and contents. In the later period, controlled application of nitrogen fertilizer, increased application of potassium fertilizer, reduction of chlorophyll in the peel, improvement of ventilation and light transmission conditions, increase of sunlight exposure, good drainage, reduction of air humidity, and spraying of hormones such as naphthyl acetic acid and 2.4-D can all promote apple growth. Color.

Apples generally drop flowers and fruits four times from the time the flower buds appear to the time the fruits are harvested. For the first time, during the final flowering period, the pedicels fall off together with the flowers, which is usually called flower drop. The second time, about a week after the flowers fall, the ovary slightly enlarges and lasts for 5-20 days, which is called early fruit drop. The third time, 7-14 days after the second fruit drop, the fruit has reached the size of a thumbnail, which has a greater impact on yield. It is called physiological fruit drop. It usually occurs in May in Yunnan. The phenological period in the north is later than that in Yunnan. It occurs in It is in June, so it is called "Fruit Falling in June". The fourth time before the fruit is harvested, mature or nearly mature fruits fall, so it is called preharvest fruit drop.

The first and second flowers and fruits drop are mainly caused by nutritional deficiencies and poor pollination and fertilization. The third fruit drop is caused by intense competition for nutrients between fruits and shoots, in addition to lack of growth hormone within the embryo. Because the osmotic pressure of leaves is greater than that of young fruits, the competition for nutrients is stronger than that of young fruits. Therefore, in addition to topping and pruning the branches to inhibit the growth of new shoots, flower fertilizers should also be applied in time to supplement nutrients. It develops from the fertilized egg in the embryo sac. The normal fruit of apple has 5 ventricles and 2 seeds in each ventricle. During the fruit development process, the seeds secrete hormones to stimulate the growth of the pulp. Therefore, those with good pollination and fertilization and plump seeds will have a correct shape and plump flesh. On the contrary, those with poorly developed seeds or no seeds will have sunken and thin flesh, resulting in deformed fruits. Therefore, Be sure to configure pollinating trees and improve pollination. Temperature: Apple trees are temperate fruit trees that like low temperature and dryness. They require no severe cold in winter and no scorching 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 of ≥10℃ is about 5000℃, and the growing season (April-October) ) The average temperature is 12-18°C, and in winter it takes 1200-1500 hours of low temperature below 7.2°C to successfully pass natural dormancy. Insufficient low-temperature time leads to delayed and irregular leaf development and flowering, and some flower buds do not even sprout. In May, the scales loosen and fall off and become dead piles, seriously reducing yields; the absolute low temperature is lower than -30--32℃, and frost damage occurs again. . According to the survey, the performance of apples in different altitude and temperature areas of Yunnan Province is as follows.

Table performance of apples in different altitude and temperature zones in Yunnan

Altitude (m) Annual average temperature (℃) High yield, fruit quality, pests and diseases, growth pattern suitability

< p>Below 1800, the weight difference of more than 15 is abnormal and not suitable

1800-2000 14-15, medium and heavier than normal, suitable

2000-2200 13-14 higher Nutritional analysis of Youqing Normally Suitable 9 Apples