The secret of apple tree cultivation technology and frost damage prevention measures is revealed
Lin Hu
At this stage, apples occupy an important position in the fruit economic system, it is not only the main force in the field of "fresh fruit supply", but also the main raw material for the production of fruit vinegar, preserved fruit, fruit wine, dried fruit and other products. At the same time, with the enhancement of modern people's health awareness, more attention is paid to dietary matching, nutritional balance and weight control, apples are suitable for almost all kinds of groups, it is rich in dietary fiber, organic acids, carbohydrates, aromatic substances, vitamins and minerals and other ingredients, with the effect of enhancing intestinal motility, whitening skin, eliminating free radicals and protecting eyesight, etc., which can not only maintain the body's energy needs, but also have a strong sense of satiety. Based on the perspective of agricultural economy, it is of great significance to vigorously promote regional apple planting, expand the scale of apple cultivation, and build an apple industry chain to implement the rural revitalization strategy.
1 Analysis of apple tree cultivation technology
1.1 Breed selection
On the one hand, the selected apple varieties should conform to the local climate, soil quality, geography and other conditions, and on the other hand, the apple tree varieties should meet the regional planning goals, especially the wishes of the government, enterprises and growers. Taking Gansu as an example, the main apple varieties include Huaniu, Gala, Fuji, Hongxing, etc. Different varieties are distributed in different regions, such as Tianshui, Qingyang, Gannan and Dingxi. At the same time, in the process of variety selection, it is necessary to take into account the disease resistance, maturity period, drought tolerance and cold tolerance of apple trees.
1.2 Garden selection and land preparation
Apple trees are adaptable, but have certain preferences, such as soil pH 6.5 is the most suitable for apple growth, the annual frost-free weather in the orchard area should be 120~180 days, and the annual sunshine hours should be 2200~2800 hours. From the perspective of the main apple growing areas in the mainland, they are mainly concentrated in 35°~40°N latitude. The selection of the garden should pay attention to local analysis, such as whether it is a sunny slope, how the soil fertility is, the distance from the surface water, etc., especially to avoid various pollution sources (such as chemical plants, garbage stations, etc.). Before planting apple trees, it is necessary to turn the soil deep and flat, reasonably match the amount of farm fertilizer and chemical fertilizer, and adjust the acidity and alkalinity of the apple cultivation garden by using quicklime, plant ash, sulfur powder, coniferous soil, etc.
1.3 Pruning Management
In terms of pruning, winter pruning (January-March) is the top priority, mainly to ensure the healthy growth of the main branches, to avoid the consumption of nutrients during the dormant period, and the pruning is mainly concentrated in the canopy part. Re-pruning is a further tree management on the basis of winter pruning, which is generally carried out after spring, germination, and before flowering, but there are many situations that need to be considered in re-pruning, including the age, variety, and growth of apple trees, taking apple trees in the peak fruit period as an example, the ratio of fruiting branches to growing branches should be controlled at 1:2 or 1:3 during re-pruning (Fig. 1).
Figure 1 Pruning
1.4 Assisted pollination
Apple tree field management runs through the entire production process, but focuses on June to August each year, and the main content includes weeding, watering, bird repellent, pollination, etc. The purpose of field management is twofold, one is to provide good growing conditions for apple trees, and the other is to lay the foundation for apple bearing to ensure yield and quality. Taking pollination as an example, if relying solely on the bee population in nature is not enough, a beekeeping team can be introduced to ensure that there are 1500~1800 bees per hectare in the apple orchard. If the apple cultivation scale is large and there is a lack of bee resources, an artificial pollination mechanism must be established. Under normal circumstances, 25 kg of pollen per hectare of apple orchards is required, and the specific operation can be carried out by point teaching method, spray method, etc. Each of these methods has its own advantages and disadvantages, such as the high success rate of point teaching (Figure 2). It is the use of brushes, cotton swabs and other media to apply apple blossom "one-to-one", but the labor cost is very high. Although the spray method saves time, it needs to be equipped with pollen liquid, which consumes a lot of pollen.
Figure 2 Point teaching
1.5 Water and fertilizer management
Water and fertilizer management is an important part of the apple tree cultivation process, and the implementation process is long and there are many influencing factors, which need to be comprehensively judged according to different periods, apple tree age, climatic conditions and soil conditions. Among them, the most critical is spring water and fertilizer management, which is related to the annual growth, yield and quality of apple trees. On the one hand, regarding the management of "three waters" in spring, 8~10 days before the budding of apple trees, digging holes and irrigating water are mainly to help apple trees resist the "cold of spring" and at the same time promote the development of capillary roots of apple trees, which is "one water". After entering the flowering period of apples, "two-water irrigation" is implemented, and nutrient solution is added at the same time as irrigation to cope with the large consumption during the flowering period. After 20 days of flowering, "three-water irrigation" is carried out, which is accompanied by a distribution of high-phosphorus, water-soluble fertilizer to ensure thorough watering at one time, with the aim of promoting the division of apple pulp cells. On the other hand, regarding the management of the "three fertilizers" in spring, the first "spring fertilizer" was carried out in mid-April, and the amino acid water-soluble fertilizer was applied by irrigating the roots. The second top dressing is carried out before and after flowering, in addition to nitrogen, phosphorus and potassium fertilizers, it is necessary to pay attention to the addition of calcium fertilizers, such as double enzyme fertilizers, calcium, magnesium and phosphorus fertilizers, etc., so as to reduce physiological diseases. The third fertilization was carried out around 20 days after the flowering of the apple tree and was dominated by phosphate fertilizer.
1.6 Pest and disease control
There are many types of apple tree diseases and insect pests, among which the more common diseases include black rot, scab, anthracnose, fly faeces, penicillium, gray spot, etc., which are all over the branches, leaves, flesh (skin) and fruit heart of apple trees, and common insect pests include red spider, whole clawed mites, pear heartworms, spiral leaf miners, scaphoid caterpillars, etc. Pest control technology includes three aspects: the basic idea of biological control is to introduce natural enemies and build a line of defense against pests and diseases in the apple planting area, such as the introduction of ladybugs, bees, spiders, etc.; physical control includes bagging isolation (Figure 3), black light trapping, insect trapping, etc.; chemical control is the main means of eliminating pests and diseases, and the apple cultivation industrial park should establish a scientific and professional guidance system for the use of pesticides, which should ensure that chemical pesticides, Hormones and other effective pests and diseases, but also to ensure that the dosage is reasonable, reduce the residue of harmful ingredients on apples.
Figure 3 Bagging
2 Apple tree frost damage prevention measures
At present, the apple producing areas in mainland China are concentrated in Shaanxi, Shanxi, Liaoning, Gansu and other places, and the climate in these regions has a long cold cycle without exception. Although apple trees have the biological characteristics of "hardy and cool", once the tolerance limit of apple trees is exceeded, they will face the problem of reduced yield or even no harvest. More importantly, the dominant factor of "frost damage" is climate, which is sudden and difficult to control, so it is necessary to do a good job of prevention.
2.1 Breeding frost-resistant varieties to enhance tree potential
On the one hand, cold-tolerant apple tree varieties can be screened, such as marshal line, summer green, black diamond, etc., and new frost damage resistant varieties can be bred through grafting. On the other hand, in the daily management process of apple trees, the tree strength is consciously enhanced, so that apple trees can improve their resilience in the state of "cold spring" and abnormal cold climate. For example, in normal years of apple tree planting, spray nutrient solution (wofonsul, brown sugar, ulcer mixture) during spring and summer,
The use of R. solanacearum root irrigation can enhance cold resistance.
2.2 Delay the pruning of apple trees and strengthen wound protection
In some years, the temperature in the apple-growing areas in the northern part of the mainland is significantly lower, and the fruit trees enter the dormant period early, in which case the pruning work can be delayed to ensure that the apple trees form a relatively stable state at low temperatures. At the same time, after pruning, it is also necessary to strengthen the protection of the wound, such as applying antifreeze and antiseptic drugs to the wound, and using petroleum jelly, edible oil and cotton yarn materials to seal and protect the wound.
2.3 Frost and snow frost damage prevention measures
After the signs of frost appear, sulfur, lime, salt, edible oil, etc. can be used to mix a whitening agent, apply from the surface upwards, and the height of the coating is controlled at about 1 meter, on this basis, you can also use straw, cotton cloth, etc. to wrap the apple trunk. At the same time, the soil temperature of the roots can be increased by irrigation, and the smoke can also be used to smoke the apple orchard to increase the temperature of the space (Figure 4), and after the snowfall, it should be cleaned before the snow melts to prevent the snow from freezing into ice or standing water.
3 Conclusion
To sum up, in order to ensure the high-quality development of the apple industry, it is necessary to strengthen the research and practice of apple cultivation technology, the author focuses on the apple cultivation environment, seedlings, pruning, water and fertilizer, diseases and pests, etc., and at the same time summarizes and summarizes the cultivation technology, puts forward the prevention measures of apple tree frost damage, so as to provide reference for the majority of fruit farmers.