Experiment on delayed cultivation techniques of red snow peach in plastic greenhouse

Hongxue peach is a very late ripening peach variety. The open field cultivation in our county is affected by late autumn rainfall and frost, so the fruit is not easy to mature. For this reason, since 2001, we have carried out delayed cultivation experiments in plastic greenhouse by adopting technical measures such as pre-promotion and post-control, delayed flowering, bagging and rain protection, temperature regulation, frost and leaf protection in plastic greenhouse. The results showed that the fruit hanging in the second year and the full fruit period in the third year could delay the fruit ripening by about 20 days, and the fruit maturity and high quality fruit rate were obviously improved.

1 the basic situation of the test shed

The test shed is located in Sangchuan Village, Lianhua Town, where the local altitude is 1456m, the average annual temperature is 9.8 ℃, the average annual rainfall is about 380mm, the sunshine hours are 2138h, the frost-free period is 166days, the soil is loess, the soil layer is deep, the content of organic matter is 0.89%, the pH value is 8.1, and the well water is irrigated. The experimental trees were planted in two plastic greenhouses with an east-west direction, with a length of 50m, a span of 7.0m, a ridge height of 3.8m and a shoulder height of 1.5m. The shoulder was provided with a 60cm-wide roll-film ventilation belt, and a working door was opened at each end of the greenhouse. The arch frame is covered with no dripping film.

2 delayed cultivation techniques and measures

2.1 planting in high-yield pits. In the first ten days of March, a high-yield pit of 60 × 60cm was dug in the greenhouse and applied with organic fertilizer 20kg and special fertilizer 0.5kg for fruit trees. it was mixed with topsoil and backfilled, watered and covered with soil. After the high yield pit was dug, the ground temperature was raised in the shed. In the middle of March, the finished seedlings of red snow peach were planted with row spacing of 1m × 2m, and Laishan honey was arranged as pollination tree according to 4 ∶ 1, with 3 rows in each shed and 50 trees in each row. Before planting, the necrotic whisker root was cut off, dipped in mud, irrigated in time after frost, the tree was covered with plastic film, fixed and dried, and the tree was high 25~30cm.

2.2 Tree control should strengthen the management of fertilizer, water and room temperature in April, May and June, promote the rapid growth of the crown, and control the crown to promote flowers in July and August. At the end of February of that year, thawing water was poured once, the shed was buckled at the beginning of March, and the tree plate was covered with plastic film. after buckling the shed, the room temperature was controlled at 16: 20 ℃, the temperature was controlled at 18: 28 ℃ in mid-March, and the humidity was 75% 85%. The greenhouse film was uncovered in the first ten days of May. For a long time, the plants were treated with potassium sulfate compound fertilizer 0.1kg, irrigated under the film, and foliar sprayed 0.3% urea + 0.5% potassium dihydrogen phosphate 2 times every 15 days to promote the exuberant growth of the tree in the early stage. In the middle of May, when the new shoot grew to 30cm, the angle was about 85 °. At the same time, the coring was carried out to promote the secondary branch. At the end of July and the beginning of August, 15% 200-fold PP333,10 was sprayed on the leaves and then sprayed again 200-fold solution PP333+ potassium dihydrogen phosphate 300x solution. For individual trees with large growth, in the middle of August, PP333 was applied according to 0.5~1g/ soil according to tree potential to control tree growth and promote flower bud formation.

2.3Fertilizer and water management adult trees apply organic fertilizer 8000kg per mu every autumn, mainly mature human and animal manure, stable manure and cake fertilizer, and topdressing during growing period. Potassium sulfate compound fertilizer 0.5kg/ plant was applied before sprouting; 0.5% potassium dihydrogen phosphate + 0.3% photosynthetic micro-fertilizer was sprayed on the leaves of new shoots at the beginning of the growing period; diammonium phosphate 0.5kg/ plant was applied at the fruit expansion stage, potassium phosphate compound fertilizer or fruit tree special fertilizer 0.5kg/ plant was applied at the hard core stage, and frozen water was irrigated once a year before freezing, and under the film after each soil fertilization.

2.4 Flower and fruit management

2.4.1 from the second year of planting, the method of buckling the shed twice a year is adopted. the first time is in the first ten days of February, the shed is covered with grass and 70% sunshade net, and the greenhouse temperature is controlled at 3-16 ℃. At the same time, in the middle of March, the trenches of deep 60cm and wide 20cm are dug around the greenhouse and filled with heat insulation plates to block the ground temperature transmission and reduce the greenhouse temperature to achieve the purpose of delaying flowering. The greenhouse film was uncovered in the first ten days of April, and the greenhouse temperature was controlled at 15: 26 ℃ 7 days before the film was uncovered.

2.4.2 Flower and fruit thinning and bagging strictly thinning flowers and fruits to control the amount of fruit left. When the flower bud is red, remove the upper flower, deformed flower, disease and insect flower, cut flower, leave the flower buds on both sides of the middle of the branch, spray 0.2%-0.3% borax to increase the fruit setting rate, the new shoot speed and long-term fruit thinning, according to 20~25cm to leave a single fruit or short fruit branch to leave 1 fruit, 3 fruit in the middle fruit branch, 3 fruit in the long fruit branch, 1 or no fruit in the bouquet-like fruiting branch, and the tree yield in the full fruit period is controlled between 5~7kg. Double-layer paper bags were set in the first and middle of June and unpacked 7-10 days before fruit ripening.

2.5 shaping and pruning

The tree is in the shape of a spindle. The adult tree has a height of 2 to 2.5 m and a dry height of 30~40cm. A bud branch after fixed stem is tied straight as the extension head of the trunk, and about 10 backbone fruiting branches are arranged at intervals of 20~30cm in the middle trunk. In summer pruning, 3 branches are retracted and 6 branches are left to maintain the leaf area of the tree body. In the early fruit stage, the backbone branch of the tree should pull the branch and pick the heart. When the backbone branch grows to 25~30cm, it continuously picks the heart to promote the second short branch. At the same time, the tree growth is strictly controlled by spraying PP333 combined with the pull branch. Remove redundant long fruit branches, overlapping branches, disease and insect branches when cutting in winter. In the full fruiting period, the tree mainly adopts pruning methods such as short truncation and lengthening branches, heavy truncation of long branches, slow release of developmental branches, retraction or thinning of senescent fruiting branches, etc., to prevent fruit parts from moving upward and outward.

2.6 Management of temperature regulation, frost prevention and leaf protection in buckle shed

In early September, the shed was fastened for the second time to prevent early frost from harming the trees and not covering the grass. After buckling the shed, the room temperature is the same as that outside the shed, keeping it at 21: 27 ℃ during the day, 16: 20 ℃ at night, and 60% relative humidity 65%. After 3 to 5 days, the room temperature should be lower than the external temperature to prolong the fruit hanging time, the daytime temperature is 20: 24 ℃, the night is 12: 18 ℃, and the relative humidity is 65% and 70%. Clean the shed surface and increase the light in the shed. On 3 consecutive cloudy days, the greenhouse supplementary light lamp is used to increase the light according to 100W/ square meters. For 4 hours a day, 0.3% photosynthetic micro-fertilizer is sprayed on the leaf surface to promote the normal photosynthesis of the tree and improve the photosynthetic efficiency. At the same time, uncover the plastic film and apply rotten chicken manure 1000kg every 5 days to increase the concentration of carbon dioxide in the greenhouse.

2.7 harvesting and uncovering film

The harvest period is in late October. According to the market demand, it is necessary to cool down and humidify timely, keep fruit hanging time, release air day and night after harvest, uncover plastic film 5 days later, fertilize, irrigate, prune and control diseases and insect pests after film removal, so as to strengthen the tree potential and cultivate new fruiting branches.

2.8 Disease and pest control

Spray Baume 3-5 °stone-sulfur mixture before sprouting. Spray 10% imidacloprid wet powder 800 times after falling flowers to control aphids, leaf moths and leaf rollers. During the growing period, the new shoots were sprayed with 80% Dasheng M45800 times, 1% avermectin EC 5000 times, and 25% diflubenzuron 1000 times to control perforation, aphids, pear heart borer, leaf rollers, leaf mites and other diseases and insects. Before bagging, spray 80% Dasheng M45800 times solution + 85% abamecarbazide 1000 times solution + amino acid calcium to kill insects and bacteria and replenish calcium. For a long time, the new shoot was sprayed with 65% Dysen zinc 500x + BT emulsion 800x + 10% polyantimycin 1000 times to control anthracnose, brown rot, perforation and so on. The roots of individual etiolated trees were irrigated with 6% Ryan 1 (chlorophyllin) 15~20g/ plant.