What are the tree management measures for peach tree cultivation?

Strengthen tree nutrition

Branch growth and leaf area expansion provide the basis for producing nutrients for flower bud differentiation, which is beneficial to flower bud differentiation. Excessive fruiting in the current year will weaken the tree vigor, leading to reduced shoot growth in that year. Conversely, if the plant grows too vigorously, it consumes too many nutrients, which instead inhibits flower bud differentiation. Therefore, tree vigor should be regulated in a timely manner to resolve the contradiction of nutrient competition among peach tree growth, fruiting, and flower bud formation, so as to facilitate the smooth progress of flower bud differentiation. During summer pruning, efforts should be made to improve canopy light exposure and increase the storage of tree nutrients, so that all parts of the flower organs develop fully. At the same time, strengthen fertilizer and water management after fruit harvest.

Strengthen pest and disease control

After fruit harvest, strengthen pest and disease control, combined with foliar fertilization, to prevent abnormal early autumn defoliation and promote leaf photosynthetic efficiency and the accumulation of photosynthetic products, thereby overcoming poor flower bud differentiation quality and pistil degeneration caused by insufficient stored nutrients.

Artificial supplementary pollination

The peach tree is a tree species with a high self-fruit-setting rate, but abnormal weather such as low temperature, rain, and frost can adversely affect fruit setting. Artificial supplementary pollination can effectively increase the fruit-setting rate, promote uniform and well-formed fruit, and tends to increase fruit size. Pollination varieties are often selected from those with large flower quantities and overlapping flowering periods. In production, when establishing an orchard, multiple varieties are mixed-planted or planted in a ratio of 1:4 or 1:5.

Artificial supplementary pollination is generally carried out as follows:

1. Collection of pollen. The following simple method is used to collect peach tree anthers: 1-2 days before the initial flowering stage, place the collected flowers of the pollinating variety on a smooth painted tabletop, gently rub the flowers by hand, then sieve to obtain the anthers; alternatively, place the flowers in an iron sieve with a 0.25 cm aperture, spread clean white paper underneath the sieve, then gently rub the flowers by hand, and the anthers will fall onto the white paper. Although this method wastes some anthers, experiments show that the anther loss rate is generally below 20%, and compared with picking anthers flower by flower with tweezers, the work efficiency can be increased by dozens of times.

2. Methods for treating pollen. The methods include natural air-drying, heated kang drying, and electric light drying.

Points to note when drying anthers: First, temperature. If the temperature is too high, the germination rate is low and the pollen yield is small; if too low, the drying time is long. The suitable drying temperature is 20-25°C, and the temperature is required to be relatively stable. Second, time. At a maintained temperature of 20-25°C, the drying time is generally about 36 hours. Third, never expose pollen to direct sunlight. The germination rate of sun-dried pollen is only 10-20%, while the germination rate of air-dried or oven-dried pollen can reach more than 50%.

3. Storage of pollen. The prepared pollen, in addition to being used for artificial pollination in the current year, can be refrigerated if there is any surplus, in preparation for pollination of fruit trees in greenhouses in winter or for use the following year. Generally, the pollen is placed in a brown glass bottle and sealed; it can also be sealed in a plastic bag, wrapped in black paper, then packed in a plastic bag, and stored in a refrigerator below zero degrees. Before use, a germination test is required. Pollen stored by this method generally retains a viability of more than 70% after one year.

4. Artificial pollination. At full bloom, the collected pollen is made into a sugar-urine pollen solution and sprayed with a sprayer. The formula for the sugar-urine pollen solution is 5 kg water + 10 g pollen + 10 g urea + 5 g borax + 100 g white sugar + a little adhesive, mixed together. Alternatively, spraying 10-20 mg/kg of PCPA (para-chlorophenoxyacetic acid) at flowering and spraying 20 mg of naphthalene acetic acid after flowering can both increase the fruit-setting rate. Prepared pollen can also be mixed with talcum powder or milk powder at a ratio of 1:5-10, then applied to flowers with a rubber tip, or put into a gauze bag and shaken on the tree so that the pollen is scattered for pollination. When pollinating, proceed from the top of the canopy and from the outside of the canopy toward the inside. Repeating 3-4 times at full bloom can significantly increase the fruit-setting rate.

5. Pollination by bees. In orchards where the pollinating variety accounts for more than 20% and is evenly distributed, releasing mason bees or honeybees at flowering can significantly increase the fruit-setting rate. The pollinating wild bee, the mason bee, has been tested and has a relatively good pollination effect, and can increase the fruit-setting rate in peach orchards by 11%. The method is as follows: 3-5 days before peach trees bloom, take the bee cocoons out of a 4-5°C refrigerator or fruit storage, put them into prepared bee nest tubes, with one bee cocoon per nest tube, the head of the cocoon facing the tube opening, and seal the tube opening with relatively thin toilet paper to facilitate the emergence of adult bees from the nest. Then hang the bee nest tubes (50 or 100 tubes bound into a bundle) on the south-facing wall of the orchard watch room, near the collection nest tubes, to facilitate recovery. Release 50-70 adult bees per mu.

Reasonably delay flowering

1. In early spring, cover the ground with crop straw to reduce ground radiation and delay ground warming.

2. Whitewash the tree trunks to reduce the trunks' absorption of solar energy.