What are the control methods for Canna leaf spot disease?
Canna
Regardless of raging winds and torrential rain, or the scorching sun, cannas mostly open facing the sky in all directions during their blooming period, except for some special varieties or cannas with their own defects caused by disease. As people have paid more attention to and grown fonder of cannas, they have gradually come to know that cannas are prone to catching leaf spot disease during the growing period if not properly cared for. However, leaf spot disease mainly harms the healthy leaves of cannas, so what should be done when this happens?
I. Symptoms
On leaves infected by leaf spot disease, reddish-brown spindle-shaped lesions or dark brown oval lesions appear, measuring 12 mm - 6 mm, or 3 mm, with dark brown edges, surrounded by a yellow halo of chlorosis, and a clear boundary between diseased and healthy tissue. In cloudy and humid weather, a sparse gray mold layer forms on the underside of the lesions.
II. Pathogen and disease pattern
Canna leaf spot disease is caused by infection with the fungus Cercospora cannae. This fungus mainly overwinters on the remains of diseased plants. After the plants sprout and grow in the spring of the following year, under suitable conditions, the pathogen spreads with the wind and infects plants, causing damage. This disease occurs in Kunming and other places in China.
III. Control methods
1. Clean the garden: in autumn and winter, thoroughly remove the remains of diseased plants from the flower garden and destroy them in a centralized manner, reducing overwintering pathogens to control the disease outbreak the following spring.
2. For flower gardens with severe disease, at the early stage of onset, spray 50% carbendazim wettable powder 600-fold solution, or 70% thiophanate-methyl wettable powder 800-1000-fold solution. To improve the control effect, the diseased leaves can first be removed before spraying.
Control methods for Canna leaf spot disease
Symptoms: Canna leaf spot disease mainly harms leaves. On infected leaves, reddish-brown spindle-shaped lesions or dark brown oval lesions appear, measuring 12 mm x 6 mm, or 3 mm x 3 mm, with dark brown edges, surrounded by a yellow halo of chlorosis, and a clear boundary between diseased and healthy tissue. In cloudy and humid weather, a sparse gray mold layer forms on the underside of the lesions.Pathogen and disease pattern: Canna leaf spot disease is caused by infection with the fungus Cercospora cannae. This fungus mainly overwinters on the remains of diseased plants. After the plants sprout and grow in the spring of the following year, under suitable conditions, the pathogen spreads with the wind and infects plants, causing damage. This disease occurs in Kunming and other places in China.
Control methods:
1. Clean the garden: in autumn and winter, thoroughly remove the remains of diseased plants from the flower garden and destroy them in a centralized manner, reducing overwintering pathogens to control the disease outbreak the following spring.
2. Chemical control: for flower gardens with severe disease, at the early stage of onset, spray 50% carbendazim wettable powder 600-fold solution, or 70% thiophanate-methyl wettable powder 800-1000-fold solution. To improve the control effect, the diseased leaves can first be removed before spraying.
How to control Canna leaf spot disease
Canna leaf spot disease affects the ornamental appearance of cannas and is a major disease during the growth of cannas. Today, the editor shares with you the control methods for Canna leaf spot disease.
Canna leaf spot disease mainly harms leaves. On leaves infected by leaf spot disease, reddish-brown spindle-shaped lesions or dark brown oval lesions appear, measuring 12 mm - 6 mm, or 3 mm, with dark brown edges, surrounded by a yellow halo of chlorosis, and a clear boundary between diseased and healthy tissue. In cloudy and humid weather, a sparse gray mold layer forms on the underside of the lesions. Below, the editor introduces the control methods for Canna leaf spot disease:
Pathogen and disease pattern of Canna leaf spot disease:
Canna leaf spot disease is caused by infection with the fungus Cercospora cannae. This fungus mainly overwinters on the remains of diseased plants. After the plants sprout and grow in the spring of the following year, under suitable conditions, the pathogen spreads with the wind and infects plants, causing damage. This disease occurs in Kunming and other places in China.
Control methods for Canna leaf spot disease:
1. Clean the garden: in autumn and winter, thoroughly remove the remains of diseased plants from the flower garden and destroy them in a centralized manner, reducing overwintering pathogens to control the disease outbreak the following spring.
2. For flower gardens with severe disease, at the early stage of onset, spray 50% carbendazim wettable powder 600-fold solution, or 70% thiophanate-methyl wettable powder 800-****-fold solution. To improve the control effect, the diseased leaves can first be removed before spraying.
The above is the article compiled by the editor on the symptoms and control methods of Canna leaf spot disease. With proper control of leaf spot disease, there is no need to worry about its impact on cannas.
Further reading:
Canna fertilization techniques, flower language, cultivation techniques, pest and disease control