Five problems in the production of growing Chinese Yam

In recent years, the author analyzed his own practice of planting twin frameless yam for 3 years, and investigated more than 10,000 local yam growers. It was found that no matter what variety was planted, there were five problems affecting the quality of Chinese yam in varying degrees.

First, yam erythema. Commonly known as rusty yam. Red spot of Chinese yam is a disease caused by nematodes. Infected during the growth period, affecting the development of tubers, small tubers, light weight. Nematodes mainly infect underground tubers and initially form reddish brown nearly round slightly concave spots on the tubers. On the seriously affected tubers, the disease spots are dense and fuse with each other, forming large dark brown patches. Control method: when sowing, use 1 bottle of root insect net potion and 50% carbendazim 250 kg per mu, combined with fertilization and watering into the sowing ditch. After that, it was poured with the same method every 1-1.5 months.

Second, Chinese yam anthracnose. This disease is the main disease that causes the early death of Chinese yam. Anthracnose mainly harms leaves and stems. The disease spot of the leaf is round to oval, the middle is grayish white to dark gray, and the margin is dark brown. The demarcation line between disease and health is clear. Prevention and treatment: Qi Miao began to spray the medicine for the first time, using 600-fold solution of chlorothalonil, and then sprayed once every 10-15 days. After the first infected spot was found on the leaves, it was alternately sprayed with 600-fold solution and 600-fold solution of thiophanate methyl.

Third, brown rot of Chinese yam. Commonly known as "rotten yam", young yam infection appears rotten, irregular brown spots or deformities, the disease becomes soft after a little rot, and the browning part of the tuber is often larger and deeper than the external spot after incision. It can be treated both in the prevention and treatment of anthrax.

Fourth, the yam bifurcates. There are two main reasons for the bifurcation of Chinese yam: ⑴ young yam tuber tip meristem bites after being bitten by insects; ⑵ fertilizer burns roots, artificial or other reasons cause yam bifurcation. The first reason was solved in the chemical treatment for the prevention and control of red spot, and the second reason should be paid attention to not to damage the root system of Chinese yam.

Fifth, flat yam. The root cause of flat yam is lack of water. The branches and leaves of Chinese yam should be watered during peak growth period and in case of drought. There used to be a folk proverb that "drought comes out of flat, wet out of circle". The more Dashan medicine is, the worse it is. We also spread the agricultural proverb "dry yam, wet taro", which also affects the drought-resistant watering of yam. It is worth mentioning that when no-deep tillage soil conditioner is used to replace the yam field, more attention should be paid to drought-resistant watering in the later stage of yam. No-deep tillage soil conditioner can play a full role only under the premise of sufficient water. However, the yam field can not accumulate water, only by ensuring that the ditches are connected, can we ensure the high quality and high yield of Chinese yam.