Symptoms of Damping-Off and Rhizoctonia Rot in Herbaceous Flowers and Their Control Methods
Damping-off and Rhizoctonia rot are the main diseases of herbaceous flowers during the seedling-raising period. Cockscomb, scarlet sage, marigold, and garden balsam are highly susceptible to these diseases. The two have different pathogens: the main pathogen of damping-off is Pythium aphanidermatum, and the main pathogen of Rhizoctonia rot is Rhizoctonia solani, but their control methods are similar. The main symptoms and control measures of the two diseases are described below:
Damping-off is a major disease of herbaceous flowers at the seedling stage after seed germination. When seedlings are affected, water-soaked lesions appear on the stem base at or below the soil surface, then the diseased area turns brown, continues to spread around the stem, and the tissue necroses, causing the seedlings to topple over. When humidity is low, white cottony mycelium grows near the diseased plants. Rhizoctonia rot can affect plants from the seedling stage to transplanting. Dark brown lesions form on the stem base, gradually become sunken, and the diseased area constricts. When the diseased area expands all the way around the stem, the plant dies standing upright, generally without toppling.
The main control measures are as follows
(1) Soak seeds in 50% carbendazim wettable powder diluted 500 times with water for 1 hour;
(2) Spray the substrate used for seedling raising with 95% Lüheng No. 1 at 3000 times dilution to sterilize it;
(3) The sowing rate should not be too large; when sowing, water the bottom thoroughly in an appropriate amount, neither excessive nor so little that no watering is needed from sowing until the heart leaves emerge; avoid the occurrence of high temperature and high humidity in the seedling-raising site; when disease is found, promptly remove diseased seedlings and the seedlings around them;
(4) At the early stage of damping-off, spray 15% hymexazol aqueous solution at 450 times dilution; for Rhizoctonia rot, spray 20% tolclofos-methyl emulsifiable concentrate (Rizolex) at 1000 times dilution; when damping-off and Rhizoctonia rot occur at the same time, spray 72.2% Previcur aqueous solution at 800 times dilution plus 50% thiram wettable powder at 800 times dilution. Spray 2 to 3 kg of solution per square meter.
The above is Zuihua Web's introduction to the symptoms and control measures of two diseases of herbaceous flowers. We hope everyone can gain something from it!
Control of Damping-Off and Rhizoctonia Rot in Herbaceous Flowers
Damping-off and Rhizoctonia rot are the main diseases of herbaceous flowers during the seedling-raising period. Cockscomb, scarlet sage, marigold, and garden balsam are highly susceptible to these diseases. The two have different pathogens: the main pathogen of damping-off is Pythium aphanidermatum, and the main pathogen of Rhizoctonia rot is Rhizoctonia solani, but their control methods are similar. The main symptoms and control measures of the two diseases are described below:
Damping-off is a major disease of herbaceous flowers at the seedling stage after seed germination. When seedlings are affected, water-soaked lesions appear on the stem base at or below the soil surface, then the diseased area turns brown, continues to spread around the stem, and the tissue necroses, causing the seedlings to topple over. When humidity is low, white cottony mycelium grows near the diseased plants. Rhizoctonia rot can affect plants from the seedling stage to transplanting. Dark brown lesions form on the stem base, gradually become sunken, and the diseased area constricts. When the diseased area expands all the way around the stem, the plant dies standing upright, generally without toppling.
The main control measures are as follows:
(1) Soak seeds in 50% carbendazim wettable powder diluted 500 times with water for 1 hour;
(2) Spray the substrate used for seedling raising with 95% Lüheng No. 1 at 3000 times dilution to sterilize it;
(3) The sowing rate should not be too large; when sowing, water the bottom thoroughly in an appropriate amount, neither excessive nor so little that no watering is needed from sowing until the heart leaves emerge; avoid the occurrence of high temperature and high humidity in the seedling-raising site; when disease is found, promptly remove diseased seedlings and the seedlings around them;
(4) At the early stage of damping-off, spray 15 % hymexazol aqueous solution at 450 times dilution; for Rhizoctonia rot, spray 20% tolclofos-methyl emulsifiable concentrate (Rizolex) at 1000 times dilution; when damping-off and Rhizoctonia rot occur at the same time, spray 72.2% Previcur aqueous solution at 800 times dilution plus 50% thiram wettable powder at 800 times dilution. Spray 2 to 3 kg of solution per square meter.
Control of Damping-Off and Rhizoctonia Rot in Herbaceous Flowers
July 14 news from China Landscape Web: Damping-off and Rhizoctonia rot are the main diseases of herbaceous flowers during the seedling-raising period. Cockscomb, scarlet sage, marigold, and garden balsam are highly susceptible to these diseases. The two have different pathogens: the main pathogen of damping-off is Pythium aphanidermatum, and the main pathogen of Rhizoctonia rot is Rhizoctonia solani, but their control methods are similar. The main symptoms and control measures of the two diseases are described below:
Damping-off is a major disease of herbaceous flowers at the seedling stage after seed germination. When seedlings are affected, water-soaked lesions appear on the stem base at or below the soil surface, then the diseased area turns brown, continues to spread around the stem, and the tissue necroses, causing the seedlings to topple over. When humidity is low, white cottony mycelium grows near the diseased plants. Rhizoctonia rot can affect plants from the seedling stage to transplanting. Dark brown lesions form on the stem base, gradually become sunken, and the diseased area constricts. When the diseased area expands all the way around the stem, the plant dies standing upright, generally without toppling.
The main control measures are as follows:
(1) Soak seeds in 50% carbendazim wettable powder diluted 500 times with water for 1 hour;
(2) Spray the substrate used for seedling raising with 95% Lüheng No. 1 at 3000 times dilution to sterilize it;
(3) The sowing rate should not be too large; when sowing, water the bottom thoroughly in an appropriate amount, neither excessive nor so little that no watering is needed from sowing until the heart leaves emerge; avoid the occurrence of high temperature and high humidity in the seedling-raising site; when disease is found, promptly remove diseased seedlings and the seedlings around them;
(4) At the early stage of damping-off, spray 15 % hymexazol aqueous solution at 450 times dilution; for Rhizoctonia rot, spray 20% tolclofos-methyl emulsifiable concentrate (Rizolex) at 1000 times dilution; when damping-off and Rhizoctonia rot occur at the same time, spray 72.2% Previcur aqueous solution at 800 times dilution plus 50% thiram wettable powder at 800 times dilution. Spray 2 to 3 kg of solution per square meter.