Learn strawberry cultivation techniques in a solar greenhouse and create a harvest orchard
Yang Xiaofei
Strawberry (Fragaria ananassa Duch), a perennial herb of the family Rosaceae, has a bright color, juicy, sweet and sour, and rich in nutrients. As a small berry with high economic benefits, it occupies an important position in the fruit and vegetable industry in northern China, because it is easy to pick, and plays an important role in the revitalization of rural industry and the development of urban agriculture and tourism agriculture to promote the integration of three industries.
Soil cultivation is the main production method of traditional strawberry cultivation in mainland China, but with continuous cropping, heavy cropping, and excessive application of chemical fertilizers and pesticides, strawberry soil cultivation has serious pests and diseases in recent years, especially the increase of strawberry soil-borne diseases, and the soil fertility of facilities has declined. In order to control pests and diseases and ensure yield and efficiency, the use of a large number of pesticides in a short fruiting cycle is difficult to ensure the green quality index of strawberry fruits, and the traditional cultivation manual management operation is inconvenient, and the fruit surface is easy to be polluted and damaged, which can easily lead to the reduction of strawberry fruit quality and yield. Issues such as the safety of pesticide residues in strawberry fruits have been questioned by consumers, which in turn has affected the sales and economic benefits of the strawberry market.
As a new modern technology, the development of soilless culture has effectively solved a series of problems faced by traditional strawberry soil cultivation, and the strawberry soilless cultivation mode using substrate has got rid of the soil restrictions and management obstacles in traditional cultivation, effectively overcome soil-borne diseases, broken the soil continuous cropping barriers, easy to control temperature and humidity, greatly reduced the use of pesticides in the cultivation process, ensured food safety and improved strawberry yield and quality, and made it easier to realize strawberry green production. Three-dimensional elevated soilless cultivation also improves the utilization of space in the facility, improves labor efficiency and comfort, and is more suitable for the combined development of strawberry picking and modern urban agriculture.
At present, the development of strawberry three-dimensional soilless cultivation technology in various parts of mainland China is unbalanced, and it is not widely used in Dalian. In order to provide scientific and technological support for the development of strawberry cultivation in facilities, after years of research and application, a relatively complete technical model of strawberry elevated soilless cultivation in Dalian has been summarized.
1. Construction of three-dimensional cultivation facilities
At present, the most common strawberry soilless cultivation elevated racks include single-layer elevated trough cultivation racks, stepped staggered cultivation racks, A-shaped brackets, etc.; In this study, A-shaped three-dimensional cultivation racks were used, with 4. 0cm×4. 0cm×6. 0cm galvanized square steel is welded into a tripod, the top is 1.2m high from the ground. 5m, the bottom span of the A-frame is 1.2m, the length of the cultivation frame is based on the span of the solar greenhouse, and one A-frame is installed every 1.5m, and the row spacing of each row of cultivation racks is 1m.
On both sides of the A-frame 30cm, 80cm, 3. 3m above the ground on the left and right sides of the main frame with a diameter of 15mm galvanized steel pipe respectively set up a row of 20cm wide, 15cm deep cultivation grooves, with ground cloth and buckles fixed into grooves. The 100g·m-2 white gardening cloth was fixed on the steel pipe of the cultivation groove with a buckle, and one drip irrigation pipe was laid in each cultivation groove, and the distance between the outlet holes of the drip irrigation pipe was less than 20cm. The black and white film with a thickness of 0.03mm is now in front of the bud, and the white side is facing outward.
The substrate is imported Indian REMMY cocoir, 30cm×30cm×12cm±2cm (5kg compressed, size before soaking), EC<0.3mS·cm-1, pH5.8~ 7. 0, Na (BaCl 2-H2 O) < 1. 0mmol ·L-1, K(BaCl 2-H2 O) <2. 0mmol·L-1, water content <18%, particle size 0~6mm, standard RHP. Dried coir needs to be soaked in water to keep it moist and filled into the cultivation trough, and high-quality commercial organic fertilizer can be added to the substrate to facilitate strawberry growth. To avoid substrate settling after watering, for seedlings with holes, the substrate filling should be flush with the edge of the cultivation groove, and if the seedlings are cultivated with bare roots, the substrate filling should be slightly higher than the edge of the cultivation groove. In order to reduce the substrate cost input in the cultivation process, coconut peat can be reused for 2~3 planting cycles, but the large roots of the strawberries in the previous season need to be removed and disinfected with horseragonin. The lost part of the substrate can be filled with a new substrate, which can be mixed evenly to ensure water retention and air permeability.
Equipped with simple water and fertilizer integration equipment, it can effectively save water and fertilizer resources, pay attention to the needs of crops for fertilizer nutrients, and use Hydro Super⁃Dos45 proportional pump to fertilize with fertilizer buckets.
2 Selection of varieties and seedlings
Choose early-maturing, shallow dormancy, easy flower bud differentiation, good yield, strong resistance, and excellent quality varieties, and the commonly used varieties are "Hongyan", "Christmas Red", "Xiangye", "Gorgeous", etc. Seedlings are the basis for strawberry cultivation with high yield and excellent fruits, and the correct selection of high-quality pest-free seedlings can ensure the cultivation benefits from the source. Seedlings 3 leaves 1 heart, stem thickness > 0. 5cm, the stem thickness of the seedlings is 0. 8~ 1. 2cm, weight 20~ 40g, 3~ 5 functional leaves, sufficient nutrient reserves, fast seedling slowness, high survival rate, strong growth ability, conducive to the germination of stolons; The stem thickness of the seedlings is too small, the growth is weak and the seedling period is long. If the stem thickness is too large, the root system is easy to age, and if the weight of the seedling is too small, the functional leaves are few, and the growth is slow, which affects the quality of the seedlings.
3 Key points of colonization and management
Before planting seedlings, the seedlings should be prevented by disease once, and the strawberry seedlings should be soaked in the rooting and sterilization mixture for 5~10min (including leaves and roots), and the water should be drained. Dipping roots before planting can effectively reduce the seedling death rate and the incidence of diseases in the later stage after planting.
The planting depth is reasonable, deep and shallow and does not leak roots. If the root system of bare-root seedlings is too long and there are too many capillary roots, 1/3 of the front end can be cut off according to the situation, and not too much; Seedlings are planted directly into the substrate trough, with the arch back facing outward, and the plant spacing is 10cm. Water the planting water in time, and keep the substrate trough moist for 2~10 days after planting. After 4 days of planting, humic acid fertilizer or probiotic fertilizer should be applied at a low concentration every 4~5 days to promote rooting.
4 Essentials of growth management techniques
4. 1 Temperature Control
Strawberry budding stage, 25 ~ 28 °C during the day, 8 ~ 15 °C at night; Flowering period, 22 ~ 25°C during the day, 8 ~ 15°C at night; Fruit expansion stage, 20 ~ 25°C during the day, 6 ~ 10°C at night; Ripening period, 20 ~23°C during the day, 8~12°C at night. To avoid pollination due to temperature, it is recommended to keep the temperature of strawberry flowers in the greenhouse at 18~25°C during the day and 8~10°C at night; When there are many fruits, keep it at 20~25°C during the day and 6~8°C at night.
4. 2 Fertilizer and water management
The fertilizer supply of soilless cultivation mainly depends on drip irrigation with water, the substrate is kept properly moist during the cultivation process, the water is given every other day, a small amount is given many times, and the fertilizer is fertilized through the fertilizer applicator during irrigation. According to the growth needs of strawberries, the fertilizer ratio and type were adjusted to meet the fertilizer needs at each stage. Use a small amount of fertilizer many times, reduce the amount of fertilizer at a time, apply 15~22kg·hm-2 of water-soluble fertilizer of large elements each time, apply 1 time in 7~10d, and pay attention to timely replenishment of calcium, iron, magnesium, zinc and other trace elements. In the early stage of flowering and budding, high phosphorus was applied once, balanced fertilizer 20-20-20 was applied in the rest of the time, and the first high-potassium water-soluble fertilizer NPK 18-9-30 was applied after pollination and fruit set, and the application rate was increased or decreased according to the growth situation. After pollination, strawberries formed small green fruits, and humic acid, fulvic acid, and alginic acid fertilizers were added to promote fruit expansion, bacterial fertilizers were applied to promote root nourishment, root protection and fertilizer absorption, and amino acid foliar fertilizers were sprayed on the fruits to turn white, and humic acid and fulvic acid water-soluble fertilizers were applied with water to increase the growth quality and brightness and color of fruit surface.
At the first flowering stage and the second stubble of flowers and buds, pay attention to timely supplementation of calcium fertilizer, calcium deficiency is easy to appear soft fruit, and amino acid foliar fertilizer containing calcium, boron and magnesium can be sprayed on the foliar surface every week. Strawberry is a continuous flowering and fruiting cash crop, its healthy growth needs available nutrients, generally 18 days after flowering into the fruit expansion stage, since then foliar spray of amino acid humic acid foliar fertilizer to ensure the yield and quality of strawberry. When strawberry fruit changed color, two times of low-nitrogen, medium-phosphorus and high-potassium fertilizer (5-20-35) were applied alternately with high potassium (18-9-30) to promote the transport of photosynthetic products to the fruit and improve the sweetness of the fruit. The surface of the coir cultivation substrate is easy to dry, and the fertilizer and water are concentrated in the middle and lower layers of the substrate, so the overall fertilizer and water conditions of the cultivation groove should be observed in the process of water and fertilizer management, and the water and fertilizer should be given according to the demand.
5 Key points of plant management
Pay attention to the timely removal of stolons and side buds, too many side buds will lead to too many strawberry leaves, and the leaves will be very small due to space constraints, which will affect the ventilation and light transmission of the plant, and easily cause flower buds to be infected with gray mold; Too many side buds will also affect the concentrated supply of strawberry nutrients to the fruit, choose the side buds on both sides of the main bud in time, generally leave 2 strong side buds, avoid consuming nutrients, and keep it as soon as possible. Remove the old leaves in time before flowering, and do not pick the old leaves during the flowering period to avoid affecting the quality of flowers and the later growth of fruits. The first stubble flowers were picked once 20 days before flowering, and the old leaves were removed once at the end of the first stubble, and the fungicide was applied once after each leaf picking. Maintain a certain functional leaf to ensure the growth of the fruit. When the flowering reaches 10%, it is necessary to release bees, 1 box·667m-2, at least 3 spleen bees, moderately active. Thinning flowers and fruits can adjust the growth potential of strawberry, and thinning flowers and fruits of three stubbles according to the 3-2-2 pattern is conducive to the formation of continuous stubble of flowers and fruits.
6 Pest control
6. 1 Disease control
The problem of heavy cropping of strawberry cultivated in traditional soil makes soil-borne diseases serious, which is an important factor limiting the yield, quality and efficiency of strawberry cultivation production, which is solved by soil disinfection, pesticide control and other methods. Coco peat cultivation can effectively avoid soil-borne diseases caused by heavy cropping, and reduce the application and labor of pesticides. In order to prevent the occurrence of diseases, 3~5 days after colonization, the combination of oxamyl and 44% methalonil plus difenoconazole plus thiomycetes can be used to prevent root rot, bacterial wilt, verticillium wilt and anthracnose. On 8~10 days after colonization, fluridine amine 200g·L-1 plus enoylmorpholine 200g·L-1 plus prochloraz plus chunleimycin plus mesomycin was used to prevent fungal diseases (such as anthracnose, root rot, powdery mildew, snake's eye disease) and bacterial diseases (such as leaf spot and bacterial wilt) It has both protection and treatment, which greatly reduces the infection of post-seedling pathogens.
At the same time, the prevention and control of pesticides is combined with the hanging sulfur fumigation lamp to prevent and control strawberry powdery mildew; During the flowering period, it is recommended to use tobacco agents (pythium, pyrimidinamide, pyrimidimamide, bacillus subtilis, pyrimecyclic amine) to control gray mold; When the humidity is high, reduce the supply of water and fertilizer, avoid excessive amount in small quantities, strengthen ventilation, and reduce the causes of high humidity incidence of diseases such as gray mold.
6. 2 Pest control
Pest prevention uses 1 agent every 15 days, and the agent is selected according to the type of pest for prevention, early detection and early treatment. Prevention and treatment of aphids can be done with 10% flufenamide, red spider predator mite biological control, split off the bottom of the old leaves and then spray mite net 2000 times the solution plus 1500 times the solution, the 2nd day to release the new California small mites, release 1 bottle for every 500 strawberries, 30 days apart for 1 supplemental release, each bottle of 1000 strawberries released.
7 Analysis of input- and output-effectiveness
Taking the 65m long and 10m wide greenhouse of this test as an example, each greenhouse three-dimensional cultivation frame is welded by galvanized square steel and 15mm diameter galvanized steel pipe, and the steel input is 2. 00,000 yuan, welding labor cost 1. 80,000 yuan; The cultivation groove is fixed with a ground cloth and buckle, the cost is about 5000 yuan, which can be used for 5 years, and the cost of coir substrate is 1. 60,000 yuan; Black and white film 3500 yuan, can be used for 3~5 years; The cost of drip irrigation and fertilizer applicator is 4500 yuan, which can be used for 3~5 years, and the fertilizer input cost is 6000 yuan. Each greenhouse planted 12,000 strawberry seedlings, with an output of 3,400kg, a high-quality fruit rate of 60%, a picking price of 60 yuan·kg-1, and a sales volume of 200,000 yuan. Soilless cultivation of coconut peat with water and fertilizer integration facilities can effectively save water and fertilizer, water and fertilizer can be applied together to reduce labor costs, three-dimensional frame cultivation avoids the traditional soil cultivation of strawberries requires a lot of manpower and heavy labor operation, the fruit surface is easy to be polluted, and the rate of high-quality fruit is low, the use of three-dimensional soilless cultivation can effectively use the barren land, saline-alkali land, etc., which can not be used for production, improve the utilization rate of land and space, and improve the production efficiency of unit land. The number and yield of strawberry seedlings planted by the elevated soilless cultivation method in the same plot are about 1. 8 times, greatly reducing the production labor intensity, reducing labor costs, making it easier to achieve labor-saving and clean production, improving fruit quality and picking customer experience, and increasing the benefits of 6~80,000 yuan·667m-2.
8 Deficiencies in coir cultivation of strawberries
The main reason for limiting the popularization and application of strawberry coir three-dimensional cultivation technology is the high initial investment cost, the composition of coco peat elevated cultivation requires coco bran substrate, cultivation frame steel, cultivation trough floor cloth, drip irrigation facilities, water and fertilizer application facilities and other materials, and coco peat should be selected after desalination treatment, EC value is lower than 0. 5 buffered coir has higher requirements for the solubility of the required fertilizer, the composition of water-soluble fertilizer is reasonable and there is no precipitation, and the cost of high-quality materials is high. There is a certain difference between coir cultivation and traditional soil cultivation in the field production technology management, coco bran itself does not contain nutrients, and the fertilizer storage capacity is limited, the elements required for the growth of strawberry soilless cultivation are all supplied with water by drip irrigation, and the quality yield is more closely related to water and fertilizer management, so the cultivation process has higher requirements for plant growth and fertilizer ratio and water and fertilizer control technology in each growth period, although elevated soilless cultivation can effectively use saline-alkali land, barren land and other land that is not suitable for the growth of horticultural crops. However, the ground in the greenhouse needs to be compacted to avoid the slope of the cultivation frame and cultivation groove due to the uneven surface.
9 Conclusion
As a renewable resource, strawberry cultivation is more conducive to the sustainable development of agriculture than peat, and at the same time, it also greatly improves the water and fertilizer utilization efficiency, reduces the occurrence of diseases, improves the rate of high-quality fruits, and promotes the yield and quality of strawberries. It is labor-saving, labor-saving, and has both beautiful and comfortable picking experience, which is more suitable for the application and development of sightseeing agriculture. In practical application, it is necessary to control the technical points of each growing environment to ensure an excellent production environment for strawberries, so as to improve economic benefits. In this study, only the production and management technology of coco peat elevated soilless cultivation of strawberry was studied, and the effects of different substrate ratios and different fertilizer ratios on strawberry quality were not discussed in detail, which can be used as the focus of future research.