Problems and Countermeasures in Potato planting

The perennial planting area of potato in Yutian County is 70,000 mu, and the yield per mu is generally 2500-3500 kg. Most potato growers have some experience and good methods in cultivation and management, but on the whole, there are still many problems in potato cultivation and management. it is summarized as follows.

I. the phenomenon of species degradation

After continuous planting for several years, potato plants often appear dwarf, clump, weak growth, leaf shrinkage, smaller, brittle or ring spots, leaf veins become dark brown, leaves are easy to fall off, and serious death of the whole plant. The main cause of species degradation is the invasion of a variety of infectious bacteria and viruses. The only way to solve the degradation is to obtain virus-free seedlings through test-tube detoxification by agricultural scientists, then produce miniature seed potatoes, and then propagate into the original seed, the first-class seed potato and the second-class seed potato. The seed potato produced by this method is the healthy seed potato.

2. Tuber malformation

When harvesting potatoes, we often see grotesque potato pieces that are different from normal potato lumps, some grow a small head on the top or side of the potato blocks, some look like dumbbells, and some grow two or three protuberances on the original potato pieces, such as tumors, and so on. Such potatoes are called deformed potatoes. This situation is due to the fact that during a period of time after tuber tubers grow normally, the tubers stop growing temporarily or grow very slowly due to high temperature or drought, resulting in epidermis aging. Later, the environment was changed or the water supply was re-supplied after suitable temperature or drought, so that the potato blocks could not continue to expand uniformly and cause deformed potatoes. In order to avoid this kind of phenomenon, we should maintain the stability of production conditions, supply water and fertilizer normally, and try not to use potato blocks with serious secondary growth as seed potatoes, so as to prevent the production of deformed potatoes.

III. Improper selection of varieties

Many factors should be considered in the selection of potato varieties. First, we should choose varieties that adapt to local climatic conditions. Take this county as an example, potatoes in Yutian County are generally sown in the middle of March. The time of emergence is around the middle of April. The monthly average temperature in July is 26 ℃. According to the temperature requirements of potato growth and the climatic conditions of the county, varieties with a growth period of more than 95 days should not be planted. The second is to choose varieties that can occupy the local market at that time. For example, the precocious variety "Zaodabai" with concentrated tubers and large and neat tubers. It can not only appear on the market early and sell at a good price, but also the white meat looks beautiful. The third is to choose varieties with good quality, high nutritional value and good edible taste, such as "Feurita" with early maturity, shallow bud eyes and smooth potato skin. Fourth, the selection of varieties should also be based on the ripening period and stubble arrangement and other factors, to achieve both upper and lower stubble, high yield and bumper harvest throughout the year.

Fourth, crop rotation is not well done.

Potato is a crop that avoids continuous cropping, and the yield of continuous cropping is not only getting lower and lower, but also the occurrence of diseases and insect pests. Rotation is better with crops such as corn and millet, and it is best not to cross-stubble with Solanaceae crops such as eggplants, tomatoes and peppers, because they are cross-infected with similar infectious diseases. If you can't reverse stubble because of land and other reasons, you must pay attention to the following two points: first, fertilize according to the characteristics of potato fertilizer. Second, pay special attention to the occurrence of various infectious diseases. The first measure is to select virus-free seed potatoes, and the second is to do a good job in field disease monitoring, timely detection of the disease, it is best to use medicine before the disease.

Fifth, broadcast all kinds of pieces are too small

There are many cases in which potato seed blocks are small, and some aim to save money by buying small seed potatoes, thinking that if there is a bud hole to dig a piece, the big or small seed potato will grow the same; some of the original seed potato pieces are not big, only the potato meat around the bud eye is dug into very small seed blocks, and the rest is eaten. In fact, these practices will lead to uneven emergence of potato seedlings, weak seedling growth and reduced yield. According to foreign data, the yield per mu of buds weighing 14 grams is 1440 kg, while that of buds weighing 56 grams is 2144.7 kilograms per mu. The yield of large buds is 48.9% higher than that of small buds. In domestic experiments, the yield of 30 grams of buds sowing is 32.6 percent higher than that of 10 grams of buds. The problem is very simple. In a word, it is the truth of "mother big son fertilizer".

VI. Excessive density and insufficient nutritional area

In order to increase the yield, some adopt the method of close planting, taking more as the win, and some have a density of 6000 to 7000 trees per mu. Less fertilization results in thin and weak stems, insufficient nutrition, and can not be high yield. for example, the amount of fertilizer application will lead to excessive growth of stems and leaves, lodging and even branch and leaf decay due to excessive population shading each other. No matter what variety is planted, it must be planted reasonably and closely according to the variety.

7. Sowing is too shallow

In daily potato production, there are many phenomena that planting is too shallow. Planting too shallow, can cause tuber exposure, green head, but also can cause underground stolon exposure can not be tuber. The sowing is too shallow, the root system is also shallow, which reduces its ability to absorb fertilizer and water, and the plant is not strong enough to affect the yield. The more reasonable sowing depth is about 10 cm, and after ploughing and cultivating the soil, the total buried depth is up to 15-20 cm.

VIII. Unreasonable fertilization

Nitrogen fertilizer plays a very important role in the growth of potato. After applying nitrogen fertilizer, the leaf color is very green, and the effect is very obvious, which is deeply loved by farmers. However, potato needs the most potassium, followed by nitrogen, phosphorus and phosphorus, and the ratio of nitrogen, phosphorus and potassium is 2.5 to 1 / 5. On this basis, when determining the amount of fertilizer application, the utilization proportion of various fertilizers in the current year should also be taken into account. due to the different utilization rate in that year, 60% of nitrogen fertilizer, 20% of phosphate fertilizer and 50% of potash fertilizer should be used in that year. To sum up, the ratio of fertilizer application must be reasonable, and the yield should not be reduced due to excessive nitrogen fertilizer.