Problems and Countermeasures in Potato Production

Zhaosu is located in the northwest border, 1720-1860 meters above sea level, with a short frost-free period and a cool climate in mountainous areas. with the adjustment of industrial structure, potato has become the main crop of our regiment.

I. existing problems

1. Climatic influence

From April to early May 2007, due to high temperature and dry soil, it was difficult for potato to emerge, seed potato was withered, and Rain Water was more after emergence, resulting in rotten seeds, lack of seedlings and broken ridges.

two。 Poor quality of seed potato

In 2007, seed potato was rotten, sick and injured, and the diseased potato was not strictly removed during seed cutting. at the same time, the infected potato was introduced into the soil by cutting knife, resulting in rotten seed and lack of seedlings, which increased the field incidence. The spread of germs was caused by the sowing of seed potatoes with germs.

3. Effect of nitrogen fertilizer

In the process of potato growth, partial application of nitrogen fertilizer resulted in luxuriant growth of the upper stem and leaves, no sun decay in the lower leaves, top-heavy and serious lodging, resulting in late tuber and low starch content and yield.

4. Improper management

Poor tillage quality, sowing too deep or too shallow will affect the emergence rate in the field. Improper chemical removal caused more weeds in the field and inhibited the growth of potato, thus affecting the yield of potato. The cultivation machinery is not matched, and the cultivation of soil is not in time, so that the growth and development environment of potato tubers in the ground can not be satisfied, the tubers are easy to pop out of the surface and form green heads. Phytophthora infestans is easy to seep into the potato field with Rain Water, which increases the incidence of tuber infection and reduces the yield.

5. Sowing is too sparse

Seed potato was cut into pieces prematurely and kept improperly, resulting in rotten seeds and dryness during sowing. Sowing late, potato buds long, mechanical damage caused by lack of seedlings in the field. Weeding is not timely, weeds grow vigorously, resulting in weeds bullying seedlings. Frost appeared in the middle of May, causing some potato seedlings to freeze to death.

6. Disease influence

Late blight is common and serious in Zhaosu reclamation area. It is mainly due to sowing potato tubers slightly susceptible to Phytophthora infestans into the ground. When there is continuous overcast and rainy weather, the humidity is more than 75% and the temperature is more than 10 ℃, disease spots appear in the leaves, and the sporangia produced by diseased leaves expand around with the wind, rain and air flow, and fall into the soil to infect the growing tubers.

II. Countermeasures

1. Seed potato quality

Select high-quality seed potato, remove bud eye necrosis, disease and injured tuber, and select healthy seed potato with regular shape, smooth skin, weight of 20g / 25g and 1 / 2 bud eyes as seed. Seed potatoes weighing less than 40 grams can be sown as a whole, and large tubers are conducive to emergence and enhance drought resistance. It is strictly forbidden to sow rotten potato pieces with virus into the soil.

Cut the seeds 2-3 days before sowing and get rid of diseased potatoes. Prepare two cutters and strictly disinfect them with 75% alcohol or 0.1% potassium permanganate solution and rotate to prevent the spread of the disease. If the potato meat changes color, it can be eliminated. After cutting into pieces, it can be kept in good ventilation to prevent decay. You can also mix seeds with fresh plant ash so that the incisions are evenly stained with plant ash. Seed potato epidermis often carries pathogens, which can be treated with 70% tocopherol and agricultural streptomycin for surface treatment, which has a better control effect on potato early blight and late blight.

two。 Seed potato transportation

15 days before sowing, the seed potato was transferred from the seed cellar to outdoor drying to break the dormancy. Keeping the surface of tuber dry can inhibit the growth and spread of bacteria and prevent seed rot after rain. Accelerating germination before sowing, promoting precocious maturity, increasing yield, eliminating diseased rotten potato and reducing the rate of diseased plants or lack of seedlings after sowing are beneficial to the whole seedling.

3. Rotation and stubble

Continuous cropping of potatoes is the most taboo, and rotation should be done. The previous crop should be wheat, corn and other crops, can reduce the disease pressure to a minimum, but also conducive to the elimination of weeds, it is best not to use the previous stubble of Solanaceae crops.

4. Sowing mode

Sow seeds when the ground temperature of 10 cm is stable at 7: 8 ℃. The suitable sowing period in Zhaosu area is from the end of April to the beginning of May. According to different types of planters, the plant and row spacing should be adjusted appropriately, with a plant spacing of 15 cm and a row spacing of 80 cm. According to the soil moisture, the sowing depth is 8 cm, 667 square meters, 4200 cm and 4500 plants, and the sowing rate is 200 kg.

5. Types of fertilization

For every 1000 kg potato, 3.5kg of pure nitrogen, 1.5kg of pure phosphorus and 8kg of pure potassium are needed. Deep application of chemical fertilizer before sowing to avoid contact between fertilizer and seeds, 667 square meters of diammonium phosphate 10kg, urea 2.5kg, potassium sulfate 15kg.

6. Field management

After ① sowing, the potato seedlings were unearthed before they were unearthed, and the potato fields dominated by Gramineae weeds were sprayed evenly with 70% 90 ml of water in potato fields dominated by Gramineae weeds, with 10.8% high efficient herbicide EC 35% 40 ml or Jingshu 90 ml. In a plot of 667 square meters with many broad-leaved weeds, 150-200 grams of bentazone was used to spray the water evenly.

After ② potato seedlings appeared, the soil was cultivated for the first time by mid-ploughing machine to increase soil temperature and promote growth, with a depth of 8cm and 10cm, combined with weeding. When the seedling height is 15cm to 20cm, the soil is cultivated for the second time with a ploughing machine to thicken and widen the ridge, provide good conditions for tuber expansion, and reduce rotten potatoes and green heads. In the early stage of potato setting, 50 grams of paclobutrazol or 200 grams / 667 square meters of paclobutrazol or 200 grams / 667 square meters of paclobutrazol can be sprayed mixed with foliar fertilizer to promote tuber expansion and yield increase.

7. Pest control

The common diseases of potato are early blight, late blight, ring rot and black stem disease. Late blight mostly occurred in more seasons and before and after the flowering of Rain Water, and was prevented and treated with Dasheng or Yinfali and Antaisheng as soon as possible. If potato aphids and 28-star ladybugs are found, monocrotophos, saidan and dichlorvos can be used alternately. In addition, according to the growth situation, foliar spraying 1% potassium dihydrogen phosphate and 1% urea solution to improve plant disease resistance and prolong the functional period of leaves, heavy plots continuous control. The interval of pesticide application is 7 to 10 days, and the outbreak period of potato in Zhaosu reclamation area is generally from mid-June to mid-August, which is accompanied by the cross occurrence of early and late blight, which should be prevented together. During the growth period, the number of prevention and control is not less than 3 or 4 times.