Impatiens root rot

Impatiens occurs in all cultivation areas, which can cause plant death.

The symptoms mainly infected the root neck and the following parts of Impatiens balsamina, the primary gray-brown disease spot, and then expanded rapidly, making the root slightly swollen and turned into black-brown rot; the root neck tissue lost water and wrinkled after decay. The aboveground part showed sudden wilting of the diseased plant, and gradually intensified, like a temporary lack of water, but irreversible after watering.

The pathogen of the disease is fungus, Rhizopus nigricans. The pathogen overwintered in the soil with the residue of the diseased plant. The soil is too wet, the temperature is high, the plant is too dense, the environment of poor ventilation is conducive to the occurrence of the disease. The disease is usually more serious from July to August.

Prevention and cure method

(1) strengthen cultivation management. Impatiens should be planted in sunny and loose soil with good drainage and neutral to slightly acidic soil with good ventilation. Do not plant in semi-shady or wet places, so as to avoid overgrowth, lodging and poor flowering.

(2) it is necessary to keep the flower bed hygienic, remove the residual leaves in time, apply fully mature organic fertilizer, and apply more potash fertilizer appropriately to promote the development of new roots and prevent rotting roots.

(3) if it is found that the wilted diseased plant of the whole plant, the soil around the root belt should be dug up and buried in another place in time, and the original soil pit should be disinfected with 1% copper sulfate solution, and then replanted after drying for 7 days; in the case of potted plants, the diseased plant should be discarded on the pot, and the flowerpot should be soaked in 1% copper sulfate solution for 1 hour, then exposed to the sun for 7 days and then planted with new soil.