COTTON :: MAJOR DISEASE :: LEAF CURL DISEASE

Leaf Curl Disease- Cotton leaf curl virus
Symptoms
Downward and upward curling of leaves and thickening of veins and enation on underside of leaves are the characteristic symptoms of the disease. In serve infection all the leaves are curled and growth retarded. Boll bearing capacity is reduced

Pathogen
  It is caused by Cotton leaf curl virus - a begomovirus of family geminiviridae. The virions are typical geminate particles, ss circular DNA, bipartite genome with DNA-A and DNA-B components.
Disease Cycle
  The primary source is the viruliferous whitefly vector Bemisia tabaci. The alternate hosts and cultivated hosts serve as virus reservoirs throughout the year. Not transmitted by seed or contact.
Management

• Management of planting date to avoid peak vector population.
• Elimination of volunteer perennial cotton and alternate hosts including malvaceous hosts like wild okra
• Use of fungus Paecilomyces farinosus which parasitizes B.tabaci. It brings down vector population.
• Foliar application of neem leaf extract and 1% neem oil resulted in 80% reduction of virus transmission.
• Vector management by application of granular systemic insecticides.