Prevention and treatment of red or withered root of kidney bean without new root

Kidney bean red root

1. Characteristics of symptoms:

From the perspective of kidney bean growth, the bottom leaves began to yellowing and thinning from bottom to top, and the growth potential was weak. If you pull out the plant, you will find that the kidney bean root system is red or withered, the root system is little or no new root, and there are red stripe disease spots on the main root of some roots. Kidney bean growth is slow, the disease is serious, affecting kidney bean pod setting, flowers and pods drop.

Second, the cause of the disease:

1. Retting roots. Too much watering leads to excessive soil moisture and poor water and air permeability in the soil, which is not conducive to the normal growth of kidney bean roots and poor root growth, resulting in underdeveloped roots, commonly known as "retting roots". When serious, the whole root system peeling or capillary root decreased.

two。 Burn the roots. Caused by fertilizers and chemicals. Excessive or unreasonable fertilization leads to root burning, and in a small number of cases, it is related to the incomplete maturity of organic fertilizer in the base fertilizer. In addition, in the case of excessive or non-uniform application of fungicides to control red roots or nematodes during planting, kidney beans will burn roots due to excessive dosage.

3. The planting is too dense. Kidney beans are planted densely, and some even plant 5-7 seeds in one hole, resulting in nutritional competition among plants. In general, kidney beans are infected with germs after the wound and there are more red roots.

4. The ground temperature is too low. In the case of too low ground temperature, the appropriate ground temperature for root growth can not be guaranteed, resulting in poor root growth, not easy to produce capillaries, and prone to root redness.

5. Root rot. In the case of excessive humidity, legume roots are easy to be infected by root rot pathogens, resulting in red roots.

6. Anthrax. There are red roots in legume roots due to anthracnose infection, usually accompanied by red sunken spots on the stems above the surface, red linear spots on the veins on the back of leaves, and so on.

How to prevent and cure kidney bean red root:

1. Irrigate root. "Deep roots and luxuriant leaves". Only when the roots are good, kidney beans can grow well. So you have to have a good root. It is recommended that every half a month to one month, root irrigation, methyl topiramate or carbendazim or bromopyronil and other agents, add rooting agent, root irrigation, can effectively reduce the death of trees. Pay attention to the large dosage, the adult stage can be irrigated with 42 to half a jin of water, it should be noted that kidney beans around the disease should be continuously irrigated for 3 times, which can effectively control the development of the disease.

two。 Water and fertilize. Watering should be done frequently with a small amount of water, a small amount of fertilizer for many times, and a reduction in the amount of chemical fertilizer used. It is suggested that the application of humic acid fertilizer or root-promoting fertilizer can maximize the normal root growth, reduce the amount of chemical fertilizer, avoid root injury or root burning, and properly reduce the poor root growth caused by low ground temperature.

3. Spray fertilizer on the leaves. Spraying foliar fertilizer containing calcium, magnesium, iron and other trace elements can promote the normal growth of leaves and, to a certain extent, improve the resistance of kidney bean to adverse environmental conditions.

4. Remove the diseased plant. Kidney beans that have occurred should be removed in time, and quicklime can be sprinkled into the soil around the removed kidney beans to disinfect the soil, kill germs and avoid large-scale infection of kidney bean Verticillium wilt.

5. The potion is applied to the hole. It is necessary to pay attention to the soil mixing treatment of the medicament, and generally carry on the mixing treatment according to the proportion of the medicament to the soil at 1:10, and pay attention to that the dosage should not be too large, which can reduce the drug damage caused by excessive or uneven application.

6. Appropriate sparse planting. It can reduce the kidney bean root competition caused by overplanting, avoid insufficient nutrition supply, and provide a suitable growth environment for the root system.