Why is the yam dug up by planting yam deformed? What is the cause of yam deformity? Is there any way to prevent the deformity of yam? Ask netizens to help solve the malformations of yam, which are mainly caused by several reasons, such as the emergence of yam, the soil quality of the planting site, the planting methods of yam, and diseases and insect pests; the following is a detailed introduction and prevention methods of yam deformities for your reference. 1. The deformity of Chinese yam: the cause of the deformity: Chinese yam is cultivated in a large area, and yam mouth and yam slices have been cultivated in the soil for at least a year. It is easy to carry root-knot nematode, anthracnose, brown rot and so on. After the cultivation of yam seed blocks with bacteria, the disease occurred in a large area under suitable conditions (high temperature and rainy season from June to July). Make the yam grow abnormally. In addition, the mouth of 1-year-old and 2-year-old yam is more expensive, and some producers want to be cheap to choose the mouth of yam which has been cultivated for 4 ~ 5 years. Due to the aging of yam mouth, it is easy to mutate, forming bifurcation, bending and other abnormal yam. Solution: 1. Cut into pieces of the yam mouth or yam to be cultivated, soak the seeds with mancozeb 500,800 times solution or carbendazim solution for 3 minutes to kill the bacteria. 2. Try to use the annual yam mouth cultivated with high quality yam beans as seed. 3. The selection of 20-25 cm thick yam mouth or cut yam pieces as seeds is beneficial to the formation of stout vines and enhance the disease resistance of yam plants. Second, the deformity caused by the soil: the cause of the deformity: 1. The quality of the soil directly affects the growth of yam tubers. The yam growing in black clay is snake-shaped and foot-shaped, and the hairy root on the surface of tuber is thick and hairy; the yam tuber grown in sandy soil is slender and not thick enough. 2. The groundwater level of the soil is too shallow, the growth of yam plants is not exuberant, and the roots and tubers are easy to rot. 3. There are many diseases and insect pests in the soil of continuous cropping plot, and the color of tuber skin becomes darker and the quality becomes worse due to the influence of hormone secreted by root. The solution is as follows: 1. Select the uncultivated land of Chinese yam for production and cultivation, which can be cultivated continuously for 3 years, trench the ridge back of the first year Chinese yam in the second year, and plant it in the first year in the third year. 2. To choose sandy loam or loam with high dry terrain, good drainage and deep soil layer, the quality of the upper and lower soil should be the same. Third, the malformation caused by the mistake of Chinese yam planting method: the cause of the deformity: 1. The depth of trenching is not enough. The yam ditch is too shallow, and the basal meristem of the yam tuber begins to grow laterally after elongating to the bottom of the ditch, growing into a foot-shaped or serpentine yam. 2. The soil quality in the ditch is uneven. Chinese yam tubers are prone to bend or deform when they encounter bricks, stones and hard soil in the process of growth. 3. The mouth of Chinese yam is placed improperly. Due to the improper placement of the mouth of Chinese yam, 2-3 stems were generated. If not dealt with in time, multiple tubers were easily formed underground, which affected the quality of Chinese yam. Solution: 1. Digging trenches should be deep enough, and the depth of trenches varies according to the varieties of yam, but most yam tubers are 1-1.3 meters long, and trenches should be more than 1.3 meters. 2. Before planting Chinese yam, mixed organic fertilizer was applied, and the soil layer of 20cm to 30cm in yam ditch was rotated for three times to make the soil fertilizer mix evenly. 3. When cutting pieces and mouths of Chinese yam, the robust buds should have an oblique angle of 45 degrees with the ground, so as to maintain the top advantage of the robust buds and inhibit the growth of other buds. At the same time, the robust buds should be placed on the side to facilitate the growth of the aboveground stems and the elongation of the underground yam tubers. 4. Chinese yam deformities caused by diseases and insect pests: 1. Grubs, mole crickets and other pests bite yam tubers or basal meristems, resulting in insect eyes or bifurcations. 2. Root-knot nematode, anthrax and stem rot harm the leaves and tubers of Chinese yam and affect the quality of Chinese yam. Solution: 1. Organic fertilizer should be fully mature and mixed with a small amount of trichlorfon to kill bacteria and pests in organic fertilizer. 2. Before planting Chinese yam, soak the seeds with carbendazim 500-800 times solution, and sprinkle the fine sand or bran mixed with trichlorfon in the planting ditch. 3. From the first ten days of June, 500-fold solution of methyl topiramate and mancozeb was sprayed every 15 days to prevent and kill bacteria. Click to get more yam planting techniques click to get more vegetable planting techniques