Bean root rot typically appears with a severe onset during the hot season.
![]()
Symptoms of the disease include damage to the roots and stems that are buried in the soil. Initially, the affected areas appear brown or dark brown, irregular in shape, and sometimes have red streaks. The lesions are slightly sunken, and the surface may crack and penetrate into the cortex. Plants in the flowering stage during spring and summer show symptoms such as yellowing of the lower leaves, withered edges, and the diseased leaves spread upward without falling off. During the high-temperature season in autumn, bean seeds germinate and become infected. The radicles develop russet-like lesions that gradually turn dark brown. The young leaves on the stems turn brown, shrink, and deform, while the older lower leaves remain relatively normal. The roots of the infected plants are sparse, and the plants are stunted. When the main roots rot or die, the upper stems and leaves begin to wilt, leading to plant death. The vascular bundles become reddish-brown. A key difference from bean blight is that the infection is usually confined to the root and base of the rhizome. Once the main root rots, it causes wilting symptoms in the above-ground parts. The pathogen responsible for bean root rot is a fungus belonging to the subphylum *Fusarium solani* (Mart.) App. et Wollenw. f. sp. *Phaseoli* (Berkh.) Snyder and Hansen. The disease spreads through mycelium and chlamydospores present in the soil, and can overwinter in manure, soil, and weeds. These sources serve as the primary infestation agents. The pathogen spreads via irrigation water, rain, tools, and fertilizers, entering through wounds. Conidiospores produced in infected tissues are dispersed by rain splash or flowing water, causing repeated infections. High temperatures (29–32°C) and high humidity create ideal conditions for disease development. Low-lying fields with poor drainage, soils with low viscosity, and areas with continuous cropping are often severely affected. The pathogen can survive in the soil for more than 10 years without a host. Seeds do not carry the pathogen, but infected or fertilized manure in the field serves as the primary source of infection in the following year. The disease spreads through rainwater, irrigation, and agricultural activities, entering the plant through underground wounds. The occurrence of the disease is closely related to the presence of the pathogen in the soil and the resistance of the bean varieties. Varieties such as Qiu Kang 6, Chun Feng 4, and Feng Shou 1 are more susceptible compared to resistant clay soils. Factors like chilling injury, application of decomposed manure, and root wounds can also contribute to the disease. In the Beijing-Tianjin region, outbreaks are particularly severe between June and August during the high-temperature season. Control methods include crop rotation: fields affected by the disease should be rotated with cabbage, onion, or garlic for more than two years, preferably using a dry-land rotation system. In seriously affected areas, soil treatment with 50% carbendazim or 40% triadimefon at a ratio of 1:500 can be used when transplanting seedlings in nutrition cups or sowing seedlings. Alternatively, a 1,000-fold dilution of liquid agents or a 1,000-fold solution of "Enemy" can be used for root watering. From emergence to the early flowering stage, the same agents can be applied at 1,000 times concentration, or 600–1,000 times diluted potassium permanganate, 20% CK at 1,200 times, or 50% thiophanate-methyl WP. These solutions should be poured at the base of the stem, once every 7–10 days for 2–3 consecutive times. Combining spraying and foliar applications, with 3–4 sprays, can enhance effectiveness.
Symptoms of the disease include damage to the roots and stems that are buried in the soil. Initially, the affected areas appear brown or dark brown, irregular in shape, and sometimes have red streaks. The lesions are slightly sunken, and the surface may crack and penetrate into the cortex. Plants in the flowering stage during spring and summer show symptoms such as yellowing of the lower leaves, withered edges, and the diseased leaves spread upward without falling off. During the high-temperature season in autumn, bean seeds germinate and become infected. The radicles develop russet-like lesions that gradually turn dark brown. The young leaves on the stems turn brown, shrink, and deform, while the older lower leaves remain relatively normal. The roots of the infected plants are sparse, and the plants are stunted. When the main roots rot or die, the upper stems and leaves begin to wilt, leading to plant death. The vascular bundles become reddish-brown. A key difference from bean blight is that the infection is usually confined to the root and base of the rhizome. Once the main root rots, it causes wilting symptoms in the above-ground parts. The pathogen responsible for bean root rot is a fungus belonging to the subphylum *Fusarium solani* (Mart.) App. et Wollenw. f. sp. *Phaseoli* (Berkh.) Snyder and Hansen. The disease spreads through mycelium and chlamydospores present in the soil, and can overwinter in manure, soil, and weeds. These sources serve as the primary infestation agents. The pathogen spreads via irrigation water, rain, tools, and fertilizers, entering through wounds. Conidiospores produced in infected tissues are dispersed by rain splash or flowing water, causing repeated infections. High temperatures (29–32°C) and high humidity create ideal conditions for disease development. Low-lying fields with poor drainage, soils with low viscosity, and areas with continuous cropping are often severely affected. The pathogen can survive in the soil for more than 10 years without a host. Seeds do not carry the pathogen, but infected or fertilized manure in the field serves as the primary source of infection in the following year. The disease spreads through rainwater, irrigation, and agricultural activities, entering the plant through underground wounds. The occurrence of the disease is closely related to the presence of the pathogen in the soil and the resistance of the bean varieties. Varieties such as Qiu Kang 6, Chun Feng 4, and Feng Shou 1 are more susceptible compared to resistant clay soils. Factors like chilling injury, application of decomposed manure, and root wounds can also contribute to the disease. In the Beijing-Tianjin region, outbreaks are particularly severe between June and August during the high-temperature season. Control methods include crop rotation: fields affected by the disease should be rotated with cabbage, onion, or garlic for more than two years, preferably using a dry-land rotation system. In seriously affected areas, soil treatment with 50% carbendazim or 40% triadimefon at a ratio of 1:500 can be used when transplanting seedlings in nutrition cups or sowing seedlings. Alternatively, a 1,000-fold dilution of liquid agents or a 1,000-fold solution of "Enemy" can be used for root watering. From emergence to the early flowering stage, the same agents can be applied at 1,000 times concentration, or 600–1,000 times diluted potassium permanganate, 20% CK at 1,200 times, or 50% thiophanate-methyl WP. These solutions should be poured at the base of the stem, once every 7–10 days for 2–3 consecutive times. Combining spraying and foliar applications, with 3–4 sprays, can enhance effectiveness.
Ointment Patch,Licorice Extract liquid,extracted from Aicao for body care,All Natural Ingredients Transdermal Patch
Jilin Manyitang Pharmaceutical Co., Ltd , https://www.likangpharmaceutical.com