Detailed Explanation of Potato Plastic Mulch Cultivation Techniques
The potato is a perennial herbaceous plant of the Solanaceae family, whose tubers are edible, and it is the third most important food crop in the world, after wheat and corn. The potato is also known as earth egg, malingshu, foreign taro, etc., and is the tuber of a Solanaceae plant. Together with wheat, corn, rice, and sorghum, it forms one of the world's five major crops. The potato originated in the Andean region of South America, and its history of artificial cultivation can be traced back at least to approximately 8000 to 5000 BC in the southern region of Peru. The major potato-producing countries mainly include China, Russia, India, Ukraine, and the United States. China is the country with the largest total potato production in the world.
Morphological characteristics of the potato:
Herbaceous, with underground stems tuberous, oblate or 15-80 cm tall, hairless or sparsely pubescent. The stem is divided into two parts: the aboveground stem and the underground stem. Oblong, about 3-10 cm in diameter, the outer skin white, pale red, or purple. The color of the tuber skin is white, yellow, pink, red, purple, and black, and the tuber flesh is white, pale yellow, yellow, black, blue-green, purple, and black-purple. Plants grown from seeds form a slender main root and branched lateral roots; while plants propagated from tubers have no main root and only form a fibrous root system. The aboveground stem is rhombic and hairy. The primary leaves are simple leaves with entire margins. As the plant grows, odd unequal pinnately compound leaves gradually form.
The leaflets are often alternating in size, 10-20 cm long; the petiole is about 2.5-5 cm long; the leaflets, 6-8 pairs, ovate to oblong, the largest up to 6 cm long and up to 3.2 cm wide, the smallest less than 1 cm in both length and width, with pointed tips, slightly unequal bases, entire margins, both sides covered with white sparse pubescence, lateral veins 6-7 on each side, slightly curved at the tip, the petiolule about 1-8, millimeters. The corymb is terminal, later lateral, the flowers white or blue-purple; the calyx bell-shaped, about 1 cm in diameter, sparsely pubescent outside, 5-lobed, the lobes lanceolate, with a long tapering tip; the corolla rotate, about 2.5-3 cm in diameter, the corolla tube hidden within the calyx, about 2 mm long, the limb about 1.5 cm long, with 5 lobes, triangular, about 5 mm long; the stamens about 6 mm long, the anther 5 times the length of the filament; the ovary ovate, hairless, the style about 8 mm long, the stigma capitate. The berry is spherical, smooth, green or purple-brown, about 1.5 cm in diameter. The seeds are kidney-shaped, yellow. The flowering period is summer.
Potato Plastic Mulch Cultivation Techniques
Plastic-mulched potatoes are mostly in the winter fallow stage during most of their growth period, with simple management, and are especially suitable for agricultural areas as a winter agricultural development project for intercropping and relay intercropping with other crops.
1. Deep plowing and land preparation before winter, and early application of organic fertilizer as base fertilizer.
Choose sandy loam soil suitable for potato growth, and after harvesting late rice or cotton, deep plow 2-3 times. In early to mid-January, in combination with deep plowing, apply 2000-3000 kg of decomposed barnyard manure or ash residue per mu as base fertilizer to promote soil maturation and loosening. At the end of January and the beginning of February, make beds 1-1.2 m wide including the ditch (ditch width about 30 cm), open a ditch in the center of the bed, and apply 40 kg of ternary compound fertilizer per mu in the ditch as base fertilizer.
2. Use improved varieties first, and carry out careful sprouting.
For plastic-mulched potatoes, it is advisable to choose early to mid-maturing varieties such as E Potato No. 1, Chuanyu Early, and Nanzhong 552, to avoid tuber formation at high temperatures. 15-20 days before sowing, cut the seed potatoes into pieces (50 g/piece or more) or use whole tubers (20-30 g/piece) for sprouting, soaking the seeds in a 1-2 mg/L gibberellin solution for 5-10 minutes; for cut seed potatoes, the soaking concentration should be lower and the time shorter. After gibberellin treatment, cover with wet river sand or wet rice straw, place in a greenhouse for sprouting, ensuring the temperature is 18-20°C and the air humidity is about 70%. After 10 days, sprouts will emerge; when the sprouts are 1 cm long, let the seed potatoes be exposed to light to encourage the sprouts to turn green and become thick and strong.
3. Sow at the right time, and plant at a reasonable density.
Before sowing, raise a high ridge 20 cm from each side of the bed, with a ridge height of 30 cm, then open a 10 cm shallow ditch on the ridge surface, place the sprouted seed potatoes in the ditch, with a plant spacing of 20 cm, sowing about 7000 holes per mu, using 150-200 kg of seed potatoes, cover firmly with fine soil after sowing, then cover the bed surface with 1 m wide microfilm, and compact the surroundings. When plastic-mulched potatoes are sown, the temperature is still low, root growth predominates, and sprouts grow very slowly. In early March, the potatoes emerge one after another, and the film must be broken in time to release the seedlings.
4. Topdressing and earthing up.
After the potatoes emerge, apply dilute human and animal urine 1-2 times according to the seedling condition to promote seedling growth. In mid-April, they enter the branching stage, and a heavy application of tuber-promoting fertilizer is needed, using 2000 kg of human and animal urine plus 10 kg of compound fertilizer per mu poured into the hills, or making holes between plants to bury the fertilizer. Plastic-mulched potatoes generally do not lack water, but during the tuber formation period (mid-April to mid-May), drought requires channeling water through the ditches, with the water level not exceeding half the ditch depth. During the branching stage, special attention should be paid to earthing up; on the one hand, it can suppress weeds under the film, and on the other hand, it promotes the potato to form more stolons, prevents the stolons from extending out of the soil and becoming aboveground branches, or prevents the potatoes from turning green when exposed to light, which plays an important role in increasing yield.
5. Harvest in time.
In mid to late May, the harvest period can be flexibly controlled according to the market and the following crop; when harvesting, pick the large ones and leave the small ones, and harvest in batches.
6. Two intercropping and relay intercropping patterns.
1. Potato + watermelon + late rice: For potatoes, make beds 1-1.2 m wide, and when sowing, leave one empty bed as a reserved row for watermelon every 3 beds sown; raise watermelon seedlings in early April, and in late April transplant watermelon on both sides of the empty bed at a spacing of 0.5 plants, two rows per bed; after the potatoes are harvested, draw a ditch in the middle of the empty bed, and combine the beds between the two wide rows of watermelon to form a wide bed of 4-4.5 m, with the vines climbing toward each other, planting 550 watermelon plants per mu; after the watermelon is harvested in mid-July, plant late rice.
2. Potato + hybrid cotton: When sowing potatoes, make beds 2 m wide including the ditch, with a bed surface width of 1.7 m, and sow one row of potatoes on each side of the bed; raise hybrid cotton seedlings in early April, and from late April to early May transplant two rows of cotton in the center of the bed, with a narrow row spacing of 0.8 m, a wide row spacing of 1.2 m, and a plant spacing of 0.4 m; after the potatoes are harvested, draw a ditch in the middle of the bed between the two narrow rows of cotton to form new bed ditches and bed surfaces, so that the two wide rows of cotton form one bed, and the two narrow rows of cotton are arranged on both sides of the bed ditch.