MySheen

Control methods of bacterial wilt of chrysanthemum

Published: 2024-11-22 Author: mysheen
Last Updated: 2024/11/22, First, the symptoms of damage: the upper leaves of the infected plant wilted for 3-5 days, the bottom leaves turned yellow, the appearance of stem nodes near the ground was brown, the succulent part of the root rotted, the epidermis and fleshy root also turned brown, and then became lead-white. The vascular bundle of the cross-sectional stem turns brown, squeezed by hand or spilled by moisturizing, and the diseased root can also be removed from.

First, the symptoms of damage: the upper leaves of the infected plant wilted for 3-5 days, the bottom leaves turned yellow, the appearance of stem nodes near the ground was brown, the succulent part of the root rotted, the epidermis and fleshy root also turned brown, and then became lead-white. The vascular bundles of the diseased stems turn brown, and the diseased roots can also flow out of the cracks when they are squeezed by hands or spilled by moisturizing. The course of the disease is short, from the onset to death only a few days, different from the long course of Fusarium wilt. Second, the morphological characteristics of pathogens: the pathogen is Ralstoniasolanacearum, short rod-shaped, single-celled, round at both ends, solitary or twin, with a size of 0.9-2.0 × 0.5-0.8 (micron). Overgrowth flagella 1-3; colony round or irregular on Agar medium, slightly raised, dirty white or dark brown, smooth with bright light. Gram staining was negative. Third, the characteristics of the disease: the bacteria overwintered in the disease residue and organic fertilizer mixed with disease residue. When there is an appropriate time in the next spring, it often invades from the root and neck wound door, mainly destroying the transport tissue, making it brown and rotten, causing the aboveground parts to die or wither. The bacteria is mainly transmitted by Cao strain, and it can also be transmitted by soil, irrigation water and agricultural tools. In the hot and rainy season, the fields with poor drainage are prone to disease, the terrain is low-lying, and the disease is serious in continuous cropping land. Fourth, control methods: (1) select disease-resistant varieties. (2) careful maintenance, timely removal of diseased plants, and disinfection of diseased points with quicklime. (3) soaking roots with Ralstonia solanacearum antagonistic bacteria MA-7 and NOE-104 can also be sprayed or infused with 72% agricultural streptomycin sulfate soluble powder 3000 times or 20% Longke bacteria suspension 500x, 50% succinic fertilizer copper wettable powder 500x, 30% Ludabao suspension 400x, 53.8% can kill 2000 dry suspension 900x-1000 times once every 7-10 days. Continuous prevention and treatment for 2-3 times.

 
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