First, the requirements of potato growth and development on the environment
1, potato temperature requirements
Potatoes are native to the alpine region of South America, and they like cold climate and are not resistant to high temperature. The temperature 17~2 1℃ is suitable during the growth period.
Seed potato: The lowest temperature of seed potato germination is 4℃, but it is very slow, and the suitable temperature for bud growth is 13~ 18℃. Sowing at high temperature, potatoes germinate first and then grow roots; Sowing at low temperature is to grow roots first and then germinate. Stem and leaf: The suitable temperature for potato stem and leaf growth is 17~2 1℃, and the most suitable temperature is about 20℃. When the temperature is below 7℃, the growth stops, and when the temperature drops to-1℃, the plants often die of freezing. When the temperature is above 25℃, the plant growth is obviously affected. At about 30℃, the aboveground growth stops, the stems and leaves become thinner, the leaf area shrinks and the stems and leaves turn yellow. Tuber: The optimum temperature for tuber formation of potato is 20℃. Generally, plants grow early at low temperature and delay at high temperature. High temperature of 27~32℃ is easy to cause the secondary growth of tuber and form deformed small potatoes. 2. Requirements of potatoes for light
Potatoes are photophobic crops. If the light is insufficient for a long time or planted in a place with too little light, the stems and leaves will easily grow in vain and the tuber formation will be delayed. Under the condition of long sunshine, stems and leaves, flowers and fruits and creeping branches all grow faster, while short sunshine is beneficial to the formation of tubers. Therefore, the requirements of potato stem and leaf growth for light length are different from those for tuber formation.
3. Requirements of potatoes for moisture
Potatoes are crops that need more water. Generally, it takes 300-600 ㎏ of water to form 1㎏ of dry matter. The yield of potato tuber is closely related to the soil water supply during the growth period.
If the soil lacks water after germination, it will have a bad influence on the growth of plants. The soil moisture should be maintained at 70%~ 80% of the field capacity at the stage of tree emergence, so as to promote the vigorous growth of stems and leaves. However, the soil moisture should be properly controlled and reduced from 80% to 60% at the stage of potato bearing. Sufficient soil moisture and uniform supply are required in the potato-bearing stage, and the soil moisture is required to reach 80% ~ 85% in this stage, and the soil moisture should be controlled in the later stage of potato-bearing to avoid tuber rot due to excessive soil moisture.
4. Requirements for soil and nutrients
Potatoes are not very demanding on soil, and they can be cultivated outside the sticky, acidic and alkaline soil. However, loam or sandy soil with more organic matter, deep soil layer, loose tissue and good irrigation and drainage conditions is the most suitable soil for potato cultivation.
Potato is a fertilizer-loving crop, so it is sensitive to fertilizer, which is the basis of yield formation. In the growth period, the absorption of potassium is the most, followed by nitrogen and phosphorus. Fertilizer demand in each growth period: Generally, plants are small in seedling stage, which requires less fertilizer. From tuber formation to tuber expansion stage, potatoes absorb nutrients quickly and in large quantities, which is the key period for potatoes to need nutrients all their lives.
Second, the management technology of potato cultivation in greenhouse
1, variety selection
In the selection of varieties, we should combine the characteristics of winter cultivation, and choose varieties with short tuber dormancy period, early tuber formation, concentrated tubers, small plant shape and erect stems. At present, the ideal varieties are Zhangshu 1, Dongbei Nong 303, Kexin 2 and so on.
2. Seed potato treatment
In order to ensure rapid and uniform emergence of seedlings, potato seed potatoes should be treated about 10~ 15 days before sowing.
(1), dicing
Selecting disease-free potatoes, the potato pieces with a weight of100g or more need to be cut into small pieces with at least 2 buds.
② Disinfection of seed potatoes
In order to prevent seed potatoes from getting sick, seeds can be soaked in formalin solution for 20-30 minutes before sowing, and covered with film for 6-8 hours after taking out.
(3) breaking dormancy and accelerating germination of seed potatoes.
The whole potato was soaked in gibberellin of 5 ~10mg/l for 30min, and the cut potato pieces were soaked in gibberellin of 0.5 ~1mg/l/0min. After drying the surface moisture, they were placed in wet sand to accelerate germination. Generally, two or three layers of seed potatoes and sand are stacked, and the upper part is covered with straw and covered with a film, and the temperature is kept at15 ~ 20℃; Sandy soil should be dry and wet, and the principle of kneading into a ball in hand and letting it go is mastered. Excessive humidity and water accumulation are strictly prohibited. In the process of artificial germination, check every 5 ~ 7 days to remove rotten seed potatoes. Generally, it will sprout after 10 days. Take out the seed potato with a bud length of1~ 2cm, and leave it in a bright place for 3 ~ 5 days to make the bud green and robust. When the pretreated seed potato bud length is1~ 2cm, it can be sown.
3. Soil preparation and fertilization
Before sowing 10 days or more, the plastic film should be buckled, and the soil preparation should be used as the border and base fertilizer should be applied to create good conditions for potato root growth and tuber expansion. Sufficient base fertilizer should be applied at one time before sowing. Centralized furrow application or spreading application before soil preparation can be adopted, and 2,000-3,000 kg of organic fertilizer, 45-60 kg of compound fertilizer, 40-50 kg of potassium sulfate and 30 kg of calcium superphosphate can be applied per mu. After soil preparation and fertilization, the border is generally wide 1.5 m and high 25 ~ 30 cm.
Step 4: sow seeds
All localities should flexibly master the sowing date according to the actual climatic conditions. It is suggested that the amount of seeds per mu of greenhouse should be 150~200 kg, and about 5,000 plants should be planted, with a spacing of 25 cm and a row spacing of 30 cm. Hole sowing or furrowing sowing can be adopted, and after sowing, plant ash or other surface fertilizers are covered, and plastic film is covered.
5. Field management
Field management after sowing is mainly in the following aspects:
(1), breaking the membrane to lead seedlings
After sowing, check regularly. When 30 seedlings emerge, the film should be broken in time to lead seedlings, and the broken film should be covered with soil after leading seedlings.
② Temperature management in greenhouse
After sowing, the greenhouse should be sealed. After emergence, if the outside temperature is low, it is best to build a small arch shed for multi-layer coverage, or cover it with sunshade net and non-woven fabric floating surface. The temperature should be controlled at 18~25℃ in the daytime and 8~ 12℃ at night. According to the temperature requirements of different potato growth periods, the greenhouse temperature can be adjusted appropriately to promote the rapid growth and development of plants.
③ Growth regulation
In winter, under the condition of sufficient base fertilizer, potatoes planted in greenhouses generally don't need topdressing, just keep proper soil moisture. However, in the actual growth process, plants may grow in vain. If this happens, the vegetative growth and reproductive growth of potatoes should be coordinated, and 50 mg/L uniconazole can be sprayed on the leaves.
④ Water and fertilizer management
If the base fertilizer is insufficient, the potato is obviously deficient in fertilizer, and the nutrition can be supplemented by foliar topdressing. Spray with 0.35% potassium dihydrogen phosphate once every 7~ 10 days, and spray twice continuously. In water management, we should master it flexibly according to soil moisture. Due to the use of plastic film mulching cultivation, coupled with the low temperature at this time, there is generally no shortage of water. However, attention should be paid to the supply of water during the potato-bearing period, which can be properly watered or dripped in the ditch. The watering time must be carried out at noon on a sunny day, and ventilation should be strengthened to reduce humidity. In the late stage of potato production, water should be controlled to prevent the tuber from rotting due to excessive soil water.
(5), pest control
The main diseases of potato during its growth period are virus disease, bacterial wilt, late blight, gray mold, etc. The pests are mainly aphids, black cutworms, crickets, ladybugs, etc., which should be prevented and controlled in time according to the condition.
The management of potato planting in greenhouse is relatively simple, but we should not neglect it, especially in the regulation of overgrowth and temperature and humidity, so as to avoid diseases.