Common blight of beans
- Name of the disease
Common blight of beans
- The scientific name
Bacteria Xanthomonas campestris pv.phaseoli
- Type of disease Family of disease
Type: bacterial
Disease family: Xanthomonadaceae
- symptoms Common blight of beans
Small, watery, transparent spots about 2 mm in diameter that turn yellowish brown as the infection progresses and are surrounded by a small halo 2-3 mm wide of pale yellow tissue. As the infection progresses, the spots coalesce and large areas of tissue die. Papers Similar spots form on the stems and petioles of the leaves, except that they are rectangular in shape, and the seeds may become infected, shrink, wrinkle, and take on a reddish-brown color.
- Causes of common blight in beans
Bacteria move between the rows of cells and secrete enzymes that decompose the middle lamina of these cells, which leads to tissue decomposition and death and the appearance of the aforementioned symptoms. Likewise, microbes emerge from the stomata to the surface of the leaves.
- Suitable conditions for the spread of common blight in beans
In warm, humid weather with or without rain at temperatures from 28°C to 32°C.
- Development cycle of common blight in beans
Bacteria are found on infected plant residues and in seeds. The infection begins with the growth of bacteria on the shoot, and thus the infection occurs in the cotyledon leaves as they penetrate the soil. They enter through cracks in the cuticle layer, and growth increases between the rows of cells until it reaches the vascular tissue, where it is transmitted through the xylem vessels and Thus, symptoms occur on the stem and leaves. Infection can then occur through the entry of bacteria transmitted by.
Wind, dirt, humans, animals, rain water, through the holes in the leaves.
- Photos of the disease at its beginning and after its spread, in high quality, at least 5 photos in high quality
- Losses of disease spread
The disease spreads throughout most parts of the world. It has been known in the United States of America since 1886. It affects most types of beans, including green and dry types.
- Control strategy
- Mechanical control
- Physical control (tillage, sanitation, pruning, solarization)
- Biocides
- Preventive measures to prevent the occurrence of the disease
1- Planting and breeding varieties resistant to the disease. It has been found that most dry seed varieties are highly susceptible to the disease.
2- Use clean seeds free of infection.
3- Remove the remains of the bean plants and dispose of them with complete care.
- Antibiotic recommendations
Use antibiotics such as Streptomycin sulphate solution at a rate of 200 parts per million, and immerse seeds whose safety is doubtful in it for 10-30 minutes. The solution may be sprayed with a concentration of 300 parts per million and a little glycerin added to it.
All references and their links must be mentioned
https://mail.almerja.com/reading.php?idm=213456
https://aerif.chrkat.com/bacterial-diseases-affecting-beans/
https://plantpath.ifas.ufl.edu/u-scout/bean/common-bacterial-blight.html
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