Blight

From Wikipedia, the free encyclopedia

This article is about plant diseases. For other senses of this word, see blight (disambiguation).

Look up Blight in
Wiktionary, the free dictionary.

Blight refers to a specific symptom affecting plants in response to infection by a pathogenic organism. It is simply a rapid and complete chlorosis, browning, then death of plant tissues such as leaves, branches, twigs, or floral organs.^[1] Accordingly, many diseases that primarily exhibit this symptom are called blights. Several notable examples are:

Late blight of potato, caused by the water mold Phytophthora infestans (Mont.) de Bary, the disease which led to the Great Irish Famine
Southern corn leaf blight, caused by the fungus Cochliobolus heterostrophus (Drechs.) Drechs, anamorph Bipolaris maydis (Nisikado & Miyake) by the bacterium Erwinia amylovora (Burrill) Winslow et al., is the most severe disease of pear and also is found in apple and raspberry, among others.
Bacterial leaf blight of rice, caused by the bacterium Xanthomonas oryzae (Uyeda & Ishiyama) Dowson.^[2]
Early blight of potato and tomato, caused by species of the ubiquitous fungal genus Alternaria
Leaf blight of the grasses

On leaf tissue, symptoms of blight are the initial appearance of lesions which rapidly engulf surrounding tissue. However, leaf spot may, in advanced stages, expand to kill entire areas of leaf tissue and thus exhibit blight symptoms!!

[edit] References

^ Agrios, George N. Plant Pathology. 5th ed. Burlington, MA: Elsevier Academic Press, 2005.
^ Oda, M., Sekizawa, Y., and Watanabe, T. 1966. "Phenazines as Disinfectants Against Bacterial Leaf Blight of the Rice Plant." Applied Microbiology 14(3):365-367.