Banana Infection chlorosis mossiac disease:Erwinia carotovora sub sp. carovora
- The disease is characterised by the presence of typical mosaic-like or discontinuous linear streaking in bands extending from margin to midrib.
- Rolling of leaf margins, twisting and bunching of leaves at the crown and a rigid erectness in newly emerged leaves
- The presence of dead or drying suckers is noticed in advanced cases referred as heart rot resulting from rotting of heart leaf and central portion of pseudostem
- Primarily infected banana plants develop severe mosaic symptoms in young growth showing broadly streaked chlorotic or yellowish green bands and patches or chlorotic mottling distributed in patches over the leaf lamina
- The leaves are narrower and smaller than normal and the infected plants are dwarf and lag behind in growth. Such plants do not produce bunches but as a virus reservoir.
Identification of pathogen:
- The causal agent of this disease is Cucumber mosaic virus(CMV). The virus is isometic, linear positive sense and single stranded RNA. The RNA is surrounded by a protein coat consisting of 32 copies of single structural protein which form isometric particles
- The primary transmission is through use of infected daughter suckers from diseased plants and the secondary spread of the disease is through melon aphid, Aphis gossypii and Aphids maidis.
- The banana gardens should be kept free from weeds.
- Infected suckers should not be used for planting.
- Weeds in the nearby areas should be removed as the virus survives in them in the off-season.
- Growing pumpkin, cucumber and other cucurbits between the rows of the banana crop should be avoided.
- Early detection by regular inspection of planting and eradication of diseased plants from the field as soon as they are noticed.
- Use of high input crop management system comprising of 10 kg farm yard manure at the time of planting and subsequently at an interval of 3 months. 1 kg neem cake, 200 gm nitrogen, 40 gm phosphorus, 200 gm potassium per plant, 4 weeding at 2 months interval up to 8 months stage.
- Spraying Methyl Demeton 0.03 per cent (0.3 ml/lit of water) at 3 to 4 weeks interval controls the vector and reduces the spread of the disease.
- Foliar spray of micronutrient (0.2% CuSo4(2ml/lit), 0.2% FeSo4(2ml/lit), 0.5% ZnSo4(5 ml/lit) and 0.1% H3Bo3(1 ml/lit of water) at 3,5 and 7th month after planting and spraying Glyphosate 2Kg per hectare to control weeds.
- Control of insect vector by spraying Phosphomidon at 1 ml per litre or methyl demeton at 2 ml per litre.
- TamilNadu Agritech Portal