Question: Citrus canker is caused by –
Options:
(a) Fungus (1)
(b) Bacteria (2)
(c) Virus (3)
(d) MLO (4)
Bacteria: Citrus canker is caused by the bacterium Xanthomonas citri subsp. citri. This bacterium infects the leaves, twigs, and fruits of citrus plants, causing lesions and scabs. These lesions can lead to defoliation, fruit drop, and ultimately reduced yield.
🔑Key Points:
Citrus canker is a plant disease that affects the citrus species.
Cause – Bacterium Xanthomonas.
Symptoms –
Brown spotting or lesions on leaves.
The lesions develop a water-soaked margin with a yellow ring around it.
Blemishes or blisters on the fruit rind.
Leaf and fruit drop in premature stage.
Fruits affected by citrus canker are safe to consume but becomes less appealing.
🛑 Additional Information::
• Some other bacterial diseases of plants are:
Crown gall – Agrobacterium tumefaciens
Common blight of beans – Xanthomonas campestris
Soft rot – Erwinia carotovora
• Some fungal plant diseases are:
Late blight of potato – Phytophthora infestans
Black rust of wheat – Puccinia graminis
Loose smut of wheat – Ustilago nuda
• Some viral plant diseases:
Tobacco mosaic disease – Tobacco mosaic virus (TMV)