In this paper, the cultivation technology of green food shoots in Yongjing County is elaborated from the aspects of variety selection, seedling selection and breeding, preparation before colonization, colonization, field management, pest control, harvesting, storage, packaging and transportation.
<h1 class="pgc-h-arrow-right" >1 variety selection:</h1>
Choose varieties with high yield, good quality and strong disease resistance, such as Shooter 101, Mantang Hong, Emperor, Caesar, Sanqingxiang and so on.
<h1 class="pgc-h-arrow-right" >2 seedlings:</h1>
2.1 Seed treatment: Spring lettuce seed treatment: soak the seeds with 20-30 °C warm water for 4h, and then scrub the mucus on the seed coat, fish out and dry. Then wrap it with wet gauze or wet towel, put it under 15-25 °C conditions to germinate, the germination period needs to be rinsed 2-3 times a day with 15-25 °C warm water, and the seeds can be sown when 80% of the seeds are white. Autumn lettuce seed treatment: Green shoots like cold and cold, and the most suitable temperature for seed germination is 15-20 °C. Autumn lettuce is generally in june-early July seedlings, at this time the climate is hot, the seeds should not germinate, the most common low temperature treatment method, that is, first soak in cool water for 12-24h, and then the seeds are bagged in a cool place, the temperature is maintained below 25 ° C, each day need to be rinsed with 15-20 ° C warm water 2-3 times, after 3-4d, 80% of the seeds can be sown when germination.
2.2 Seedling breeding method: the use of acupuncture disc seedlings. Process: Matrix pre-wetting - loading - pressing nesting - sowing - mulching - film opening - seedling management. Select high-quality commercial seedling substrate with 128-hole burrowing disc. The height of the substrate is generally 0.5 cm from the upper edge of the hole plate, and it is scraped flat with a ruler; the treated seeds are evenly sown on the substrate, sowing 1-2 seeds per hole; using automated sowing, only 1 seed per hole is sown. After sowing, it is covered with vermiculite, and then scraped flat along the upper edge of the nursery plate with a ruler to remove the excess vermiculite, and then the sown hole plate is placed neatly on the seedbed for filming, and the film is removed after the seedlings emerge.
2.3 Seedling period: Spring lettuce is bred in the nursery in February to March, and autumn lettuce is bred in June and July, and the seedling period is 30d. Watering and fertilizing at the seedling stage: The seedling tray after sowing is watered in time, watered thoroughly at one time, and watered more than 2 times a day to ensure that the substrate is moist, and the watering is moderate for the bottom hole of the hole plate. Spray 0.5% urea with water once as the seedlings grow 4 true leaves. Inter-seedling: 4d after sowing, the seedlings begin to emerge, and when the real leaves are exposed, the inter-seedlings are required to be one seedling per hole, and the inter-seedlings are watered in time after the inter-seedlings.
2.4 Disease and pest control at the seedling stage: After the seedlings are unearthed, they are fumigated once a week with bacteriobacterium clearing and cypermethrin smoke agent. Temperature control: the temperature is not higher than 20 °C during the day, and not less than 10 °C at night. Refining seedlings: 6d before colonization, refine the seedlings, gradually extend the time to uncover the shed film during the day, let the sun be directly exposed, postpone the curtain release time at night, and continuously improve the adaptability of the seedlings to the external environment, and finally achieve the seedlings' full adaptation to the external environment.
<h1 class= "pgc-h-arrow-right" >3 Prepare before colonization</h1>
Fertilizer requirement: Pure nitrogen (N7.7kg, pure phosphorus (P2O53.0kg, pure potassium) (K2O11.4kg) absorbed in the soil is 2:1:3, which belongs to potassium-loving crops. Land preparation: every 666.7 thirty application of organic fertilizer 800-1000kg, potassium fertilizer 8-10kg, compound fertilizer 60kg evenly spread, with a rotary tiller deep turning, the land is flat, the soil is finely crushed, no larger soil blocks. Ridge: 70 cm wide, 30 cm furrow, 20 cm high. The ridge surface is covered with mulch film, and the mulch film is required to be flattened, close to the ridge surface, and compacted on both sides to prevent the spring wind from revealing the film.
< h1 class = "pgc-h-arrow-right" >4 colonization</h1>
Colonization period: spring shoots are planted in 3-4 parts per month, and autumn shoots are colonized in July and August. Colonization density: The colonization density should be determined according to the characteristics of varieties, climatic conditions and soil fertility, etc., the general colonization row spacing is 40cm, the plant spacing is 20-25cm, and 5500-6500 plants are colonized every 666.7m2. Colonization method: double-row plum type colonization.
<h1 class="pgc-h-arrow-right" >5 field management</h1>
Slow seedling stage: 2-3d after colonization, water the seedlings slowly, and then combine with the cultivation of soil 1-2 times, the weather is hot and dry in the early stage of the growth of autumn shoots, and it should be watered appropriately many times to keep the soil moist. Rosette stage: combined with watering, nitrogen fertilizer (N3-5kg, potassium fertilizer (K2Ol-3kg) per 666.7 m2. Succulent stem formation period: keep the soil moist, combined with watering, and apply nitrogen fertilizer (N2-4kg) every 666.7 m2, no fertilizer within 20 days before harvest.
<h1 class = "pgc-h-arrow-right" >6 pest control</h1>
Agricultural control: implement 2-3 years of crop rotation, select disease-resistant varieties, create suitable reproductive environment conditions, cultivate seedlings of the right age, test the soil for balanced fertilization, apply harmless organic fertilizer, and rationally use chemical fertilizers. After harvesting, the dead branches and weeds are cleaned up in time, and the harmless treatment is concentrated to keep the countryside clean. Physical control: Hang yellow plates in the field, one per 10x2m2, set between rows, hang 15 cm away from the plant, and trap whitefly, aphids and American spotted diving flies. Chemical control: use according to the requirements of Appendix A.
Downy mildew: 72% Pulik wettable powder 800 times liquid, or 30% enoyl morpholine suspension 1000 times liquid or 75% Bacillus clear wettable powder 600 times liquid spray. Gray mold disease: 50% humus fungus wettable powder 800 times liquid, or 30% pyrimidine suspension 1500 times liquid spray. Viral diseases: spray once with 10% imidacloprid wettable powder 1000 times liquid. At the beginning of the disease, 20% virus A wettable powder 1500 times liquid or 3% ateling wettable powder 1000 times liquid was sprayed. Brown spot disease, black spot disease: at the beginning of the disease, spray 75% Bacillus Qing wettable powder 1000 times liquid plus 70% methyl tolbuzin wettable powder 1000 times liquid, or 50% paraheine wettable powder 1500 times liquid. Stem rot: Sprayed with 72% agricultural streptomycin soluble powder 4000 times liquid at the beginning of the disease. Powdery mildew: Sprayed with 15% triazolidone wettable powder 1500 times liquid at the beginning of the disease. Aphids, whiteflies: 10% imidacloprid wettable powder 1000 times liquid spray, red spider can use 8% acealoid emulsion 6000 times -8000 times liquid.
<h1 class= "pgc-h-arrow-right" >7 Harvesting, storage, packaging and transportation</h1>
Harvesting: Green shoots can be harvested after about 65 days of colonization, and the height of green shoots can reach 45cm, and the heart and outer leaves are usually harvested. Storage: cold storage, the green shoots to be stored in 3-5 units, into a film bag thickness of 0.03mm, sealed packaging, the yard is placed on the rack of the cold storage, under the appropriate temperature and humidity conditions can be stored for about 3 weeks. Transportation and packaging: Long-distance transportation should be transported by insulated vehicle at the right temperature, and bamboo baskets and plastic baskets with good support performance should be used to reduce mechanical injury and prevent browning.