Uncover the key techniques of cultivating the "T" shaped trellis of the grape canopy

Uncover the key techniques of cultivating the "T" shaped trellis of the grape canopy

Liu Ya et al

Funds: Hebei Province Modern Agricultural Industry Technology System Innovation Team Project (HBCT2021230404), Shijiazhuang Innovation Ability Improvement Program Project (198490157A)

With the improvement of people's living standards, the demand for grapes has increased, and the grape planting area has expanded year by year. As an effective means to extend the supply period of fresh fruits, facility viticulture has become a leading industry in some areas to improve the planting structure and increase farmers' income. According to reports, the mainland has an area of more than 2.8 million acres of facility grapes, and has become the country with the largest facility grape planting area in the world. At present, the traditional trellis cultivation method has many problems such as excessive planting density, low fruiting parts, vigorous growth of branches, poor ventilation and light transmission, etc., which affect the coloring and flavor of grapes, and the quality of fruits is very unstable. In addition, the increase in labor costs has led to the rising cost of grape planting, which has led to a decline in the production efficiency of grapes. The intensification of competition in the grape market and the change of people's lifestyles have prompted sightseeing and grape picking to become a good way for citizens to enjoy leisure and entertainment, and the grape industry is facing the problem of transformation and upgrading.

The cultivation of the "T" shaped trellis with a large canopy of grapes is a good fit for this development. This model reduces the planting density and increases the fruiting part of the grapes, and the main vine is perpendicular to the tree row, extending horizontally along the shelf, and the new shoots and the main vine are vertically and horizontally distributed on both sides of the main vine. This is not only conducive to the ventilation of the orchard, reducing the occurrence of pests and diseases, but also easing the tree momentum, reducing the summer pruning workload, saving labor, facilitating mechanized operation, and suitable for sightseeing picking. Moreover, horizontal leaf curtains are set between the rows, which can make full use of light to form photosynthetic products, thereby improving fruit quality, and has good stable yield and high yield. In order to promote the production and promotion of this model and guide the majority of fruit farmers to improve their planting technology, with reference to the research results in recent years and combined with the author's planting experience, the key technology of "T" shaped trellis cultivation of large canopy of facility grapes was summarized, in order to provide reference for the cultivation and rain-shelter cultivation and production of facility grapes in northern China, especially for the sightseeing picking gardens and boutique grape production gardens that carry out mechanized production.

1 Facility structure

1.1 Solar greenhouse

The orientation of the greenhouse construction is to sit north and face south east and west, 5~7 ° west, the distance between the front and back of the greenhouse is 2.5 times the highest point of the shed, the width of the shed is 8~10 m, the height of the shed is 3.8~4.5 m (0.5 m underground), and the length of the shed is 50~80 m.

1.2 Shelter from rain

1.2.1 Single rain shelter

The direction is north-south, the width of the shed is 10~12 m, the height of the shed is 3~3.5 m, the height-span ratio is 1:3~4, the distance between the arches is 1~1.2 m, the length-to-width ratio of the rain shelter is greater than 5:1, and the length is 60~100 m.

1.2.2 Multi-story rain shelters

The direction is north-south, the span of a single building is 6~8 m, and the height of the shed can be adjusted appropriately according to the production needs, with a shoulder height of 2.5~3 m and a ridge height of 1.5~1.8 m.

2 Varieties to choose from

Grape varieties cultivated in the "T" shaped trellis mode with large canopy should have strong aroma, strong growth, low light tolerance, easy flower bud differentiation, suitable for sightseeing and picking, and the yield and quality can better meet their cultivation goals. According to the requirements of different cultivation purposes and maturity periods, early, medium and late ripening grape varieties can be selected, such as early-ripening varieties 'South Taihu Lake Extra Early', 'Summer Black', 'Golden Honey', medium-ripening varieties 'Baoguang', late-ripening varieties 'Sunshine Rose', etc.

3 Colonization techniques

3.1 Preparation before colonization

According to the planned row spacing, dig a planting ditch with a width and depth of 0.6 m, apply 4~6 m 3 of rotten cattle and sheep manure per mu, mix with the soil and backfill 0.5 m, and then fill the surface with plain soil, and then water it thoroughly and solidify, and prepare for planting.

3.2 Planting

In mid-March, the soil thaws to the point of colonization before budding. The planting density can be adjusted according to the space and production needs in the facility, and the plant spacing is generally 2~3 m and the row spacing is 3~8 m. The combed and pruned roots were spread out and placed in the planting hole, and the roots were retained at 15~20 cm. When the soil fills more than the root system, gently lift the seedlings and shake, and the planting hole is filled with soil and then steadfast, so that the rhizome of the seedling is level with the ground, and the seedlings are watered thoroughly in time after planting.

4 Management Techniques

4.1 Rack and tree

Scaffolding is chosen for trellis planting. The scaffolding is made of steel frame columns and iron wires, with a height of 1.8~2 m, and a wire is pulled for each row of columns in the east-west direction, and an iron wire is pulled every 0.3~0.4 m in the north-south direction, and each wire is straightened with a tensioner and fixed on the column to form a supporting structure for grape trellis cultivation.

The tree has a single-stem, double-arm "T" shape. In the year of planting, the main stem and main vine were mainly cultivated, the height of the main stem was 1.65~1.85 m, and the "T" shape of single stem and double arm could be cultivated in the same year, that is, the two arms were retained as the main vine at the top of the main trunk, and the main vine was tied horizontally to the wire, and the fruiting branch groups were evenly distributed on the arms according to the spacing of 10 cm.

4.1.1 First year management

After planting and germination, a new shoot with strong growth is selected, and the pillar is vertically pulled and cultivated into the main trunk. In the process of trunk formation, the number of leaves was increased, the photosynthetic area was increased, and the rapid growth of the trunk was promoted. The two leaves of the secondary shoots on the main stem are not topped, and the new shoots are topped to promote the new shoots after the height reaches the predetermined height, and two new shoots with strong growth are selected from the secondary shoots extracted under the topping mouth and are horizontally pulled on both sides to cultivate the main vine.

A pair of shoots (fruiting mother branches) were left every 10 cm on the main vine, and 9-leaf secondary tips were cultivated according to the 4:3:2 or 3:3:3 pattern, that is, the first topping was carried out when the fourth or third leaf grew to a width of 1 cm, the second topping was carried out when the third leaf grew to a width of 1 cm, and the third topping was carried out when the second or third leaf grew to a width of 1 cm. For every 1.2 m extension of the main vine, leave 1 m for heavy topping, promote the secondary shoots, and repeat several times according to the row spacing until the shelf surface is full.

Winter pruning was completed from 20 days after leaf drop to 1 month before the wound flow. During winter pruning, the goal was to cover the shelf surface, leave two buds for the branches with a diameter of 0.8~1.2 cm, and cut the branches with a diameter of less than 0.8 cm at the base of the main vine to be 1 cm long, and the rest were all cut off.

4.1.2 Management in the second year and beyond

After bud break, the buds on the main stem are completely erased. The new shoots (fruiting branches) emitted from the fruiting mother branch are fixed with wire binding or tying device when they grow to about 6 leaves, and are vertically pulled and tied with the main vine, and the same side is selected and retained according to the spacing of 18~25 cm.

Fruiting branch topping is generally carried out 1 week before flowering, at the position of the adult leaves above the inflorescence. After topping, all the secondary tips below the inflorescence are erased, and one leaf is left above the inflorescence to be topped.

In winter, leave 1~2 full buds on the fruiting mother branch for pruning. The principle of pruning is to stay near and not far, strong and not weak, and leave not to stay, the purpose is to form an ideal frame and tree shape, prevent the fruiting part from moving outward, and control the amount and yield of fruiting branches of the tree. After 1~2 years of management, the "T" shaped scaffolding is basically formed, and the subsequent management method is the same as the second year.

4.2 Soil management

The large canopy "T" shaped trellis cultivation mode has a wide space under the tree, and the soil management mode should adopt the method of grass growth between the rows. Orchard grass can increase the content of soil organic matter, improve soil structure, enhance the ability of micro-environment regulation, reduce the occurrence of air and sunburn, and reduce the cost of pest control, which is the preferred soil management method for building environmentally friendly, labor-saving, efficient and high-quality orchards.

4.2.1 Naturally growing grasses

Use the grass seeds that naturally live in the soil to germinate and grow, and remove the weeds with high degree of lignification, tall, easy to string roots and entanglement, these vicious weeds can compete with the grape vine body for fertilizer and water.

4.2.2 Artificial grass planting

It is advisable to choose grass species with strong adaptability, rapid growth, long mulching period, shallow root system, shade tolerance, trampling resistance, and no common pests and diseases or host relationship with grapes, such as ryegrass, white clover, alfalfa, etc., and sow them from late April to early May.

4.2.3 Grass Management

After manually sowing grass seeds, it is advisable to use sprinkler irrigation to water in time to ensure the emergence rate. Other growth times are managed according to the actual water and fertilizer needs of grapes, and watering and fertilizing are not specifically aimed at grass. In addition, weeds should be removed in time at the early stage of weeding and in the rainy season, and the occurrence of weeds can only be controlled after the grass has fully covered the ground.

4.2.4 Use of Fresh Grass

Mechanical mowing was performed when the grass seed grew ≥ height of 40 cm. The number of mowing depends on the growth of the grass, and the mowing grass can be covered under the tree tray or collected and piled up for composting, which plays a role in improving soil structure, increasing soil nutrition, and strengthening the grape vines, while reducing the labor cost of hoeing and reducing the input.

4.3 Water and fertilizer management

The integrated technology of water and fertilizer has the characteristics of water saving, energy saving, labor saving, high efficiency and environmental protection, and has been widely used. For vineyards with large canopy "T" shaped trellises, it is advisable to adopt water-saving drip irrigation plus sprinkler irrigation and fertilization with water (except for basal fertilizer) integrated water and fertilizer management technology, and at the same time install drainage facilities to ensure waterlogging drainage.

4.3.1 Before Wintering

Freeze water at the right time and water thoroughly to enhance the frost resistance of the grapes by increasing the moisture content of the soil.

4.3.2 Pre-Embryonic

Combined with the rising temperature, the amount of irrigation should be sufficient, and it is advisable to penetrate 50~60 cm underground, and apply 5~10 kg of balanced water-soluble fertilizer per mu to ensure that the branches germinate neatly.

4.3.3 Before flowering

About 10 days before flowering, the flower water was irrigated, and the irrigation amount was slightly larger, and 5 kg per mu of high-nitrogen and high-phosphorus water-soluble fertilizer was applied with drip irrigation. At the same time, foliar spraying of 800~1000 times of amino acid foliar fertilizer can promote flower bud differentiation and improve the fruiting rate.

4.3.4 Fruit expansion period

The grapes grew rapidly during this period, requiring multiple fertilization and timely watering. At the young fruit stage, a balanced water-soluble fertilizer can be applied once, with a dosage of 5~7.5 kg per mu, and in the middle and late stages of expansion, medium nitrogen and high potassium are the main ones, with a dosage of 5~7.5 and 2.5~5 kg per mu, respectively, and liquid calcium and magnesium fertilizer and 800~1000 times of amino acid foliar fertilizer can also be sprayed on the foliar surface at this stage to promote fruit development and improve fruit quality.

4.3.5 Fruit coloring period

A small amount of water should be irrigated many times, and potassium fertilizer should be increased at the same time, phosphorus fertilizer should be applied less, nitrogen fertilizer should be controlled, and 5~7.5 kg water-soluble fertilizer should be applied per mu; liquid calcium and magnesium fertilizer can also be sprayed on the foliar surface to speed up sugar and coloring, prevent fruit cracking, and no more fertilization and irrigation should be applied 1 week before harvesting.

4.3.6 After fruit harvest

Generally, the basal fertilizer is applied in September by furrow application. That is, the ditch was opened at 40~50 cm on one side of the tree, and the ditch was deep to the concentrated distribution area of the root system, and the next year was carried out in turn on the other side. Fully decomposed cattle and sheep manure is the main fertilizer, and 4~5 m 3 is applied per mu, and medium and trace element fertilizer and phosphorus and potassium fertilizer are applied at the same time.

4.4 Flower and fruit management

4.4.1 疏穗

In the inflorescence separation stage, the panicle was thinned according to the characteristics of the variety and the expected yield, and the strong branches left double spikes, the moderate branches left single spikes, and the weak branches did not leave panicles. At the same time, the fruit ears were reshaped and pruned, and the secondary panicles that affected the spike shape and the overdense spikelets in the middle part were cut off to ensure consistent flowering and fruit setting and improve the fruit setting rate.

4.4.2 Fruit thinning

When the grape fruit and mung bean are large, the fruit is thinned, and the small fruits, over-dense fruits, deformed fruits and diseased and insect fruits on the fruit ears can be divided into multiple times, and the fruit spacing can be adjusted, and each fruit spike retains 60~100 grains according to the size of the fruit of the variety, and the yield is controlled at 1500~1800 kg per mu.

4.4.3 Bagging

Spray fungicides and insecticides in time after grain thinning and shaping, focus on spraying fruit ears, and then bag after the liquid medicine is dry, pay attention to avoid dew and high temperature at noon, until the fruit is picked up about a week before harvesting.

4.5 Pest and disease control

Due to the good ventilation and light transmission of this planting mode, compared with the conventional dense plantation, the incidence is less and milder, and the focus is on the prevention of diseases such as gray mold, anthracnose, powdery mildew and downy mildew, as well as pests such as green blind bugs, thrips and mites.

At the same time, it is necessary to pay attention to physiological diseases such as air burning and sun burning, such as some grape varieties are prone to air burning from the young fruit stage to the hard core period (June to July), mainly due to the high temperature and high humidity conditions, resulting in water imbalance, fruit browning, depression and other symptoms, which seriously affect the quality and commodity value of grapes, after the grapes are expanded, the use of a shading net with a light transmittance of more than 70% to block the fruit ears, or before 9:00 a.m. and 5 p.mAfter 00 hours, moderate water spraying should be carried out to cool down, and irrigation should be reduced before the high temperature comes, and drainage should be carried out in time after rain to ensure the normal physiological metabolism of the root system. In addition, opening vents during high temperature periods and using sprayers, fans and other facilities to promote air flow in the facility can also relieve the environmental pressure of high temperature and high humidity.

4.5.1 Agricultural control

In winter, the vineyard should be cleared, the branches and fruits damaged by diseases and insects should be removed in time, and the ecological environment of the vineyard should be improved by taking them out of the shed for centralized harmless treatment; the ecological environment of the vineyard should be improved; the water and fertilizer management should be strengthened, the density of branches and leaves should be adjusted, the tree strength should be strengthened, and the immunity of the tree should be improved; the temperature and humidity should be reasonably regulated, and the occurrence and spread of diseases and pests should be reduced.

4.5.2 Physical control

Install insect nets at the vents, and hang yellow and blue sticky insect boards and insecticidal lamps in the facility to trap and kill insects.

4.5.3 Biological control

According to the occurrence of insect pests in the field, natural enemies (such as lacewings, small flower bugs, mite-eating ladybugs, etc.) are manually released or targeted microbial pesticides, plant-derived pesticides, mineral-derived pesticides, etc. are selected for effective control.

4.5.4 Chemical control

Before germination, broad-spectrum insecticides and fungicides are generally used, such as sulfur powder + tetrachlorantraniliprole + octachlor, etc., to eliminate overwintering pathogens and eggs; germination, leaf development, flowering to bagging are the key periods of pest control, it is recommended to spray pyrazole • enoylmorpholine/mancozeb + iprodione/fludioxonil + fludioxamide • biphenyl/spiroethyl ester • pymetrozine; pay attention to protect the leaves after bagging, you can alternately use lime-reduced Bordeaux liquid and broad-spectrum protective fungicide. To avoid the development of resistance, it is recommended to use a variety of insecticides and fungicides with different control mechanisms.

5 Discussion and conclusions

The mainland is the world's largest producer and consumer of table grapes, and the grape industry plays an important role in rural revitalization, but the proportion of high-quality grapes is not high, so improving the quality of grapes has become an urgent problem to be solved in the production of grapes in the mainland, and the appropriate cultivation mode plays a key role in it.

The "T" shaped trellis cultivation mode of large canopy of grape in the facility has low planting density and large space between rows, and the yield increase in the early stage is relatively slow. In order to make more efficient use of land resources, the ecological conditions can be improved through the soil management model of grass growing between rows, creating a soil environment that is suitable for grape growth, has a good structure and is optimally fertile. Once the tree shape is cultivated in the later stage, the skeleton of the tree body is clear, the branches are evenly distributed, the light condition will be improved, the shaping and pruning work can also be standardized, saving labor and time, greatly reducing the daily workload, the yield is relatively stable, the fruit quality is relatively high, and the purpose of reducing costs, improving quality and efficiency can be achieved, and there are good development prospects.

The core technology of this cultivation model is the cultivation of a single-stem, double-arm "T" shaped tree, but in view of the vast territory of the mainland and the differences in environmental conditions in various places, it is necessary to adapt measures to local conditions and apply flexibly according to the actual situation when promoting and applying. At the same time, according to the management of different stages of the year, plan in advance, reasonably arrange agricultural activities, adjust the balance between vegetative growth and reproductive growth, underground and aboveground in each period, do a good job in pest prevention and meteorological disaster monitoring, and pay attention to recording production files, so as to facilitate the production of high-quality standardized products and promote the high-quality development of the grape industry.