The potato crop is affected by a large number of virus diseases resulting in deterioration in the

quality of seed stock and low yield of tubers

Viral diseases of potato

Mild Mosaic

(Potato Virus X, PVX)

The disease is known to occur

world wide where the crop is

grown regularly.

Symptoms

Mild mosaic (patches of normal

and light green areas on the leaf)

is the general symptom clearly

visible on young plants.

Leaflets are malformed and

death of leaf tip.

Mode of spread of Potato Virus X, PVX

– Infected tubers

Contact between diseased and healthy plants

Severe Mosaic (Potato Virus Y, PVY)

known to occur throughout the world.

Symptoms :The disease induces severe symptoms like crinkling (uneven leaf blade), rugosity (roughness), necrosis (death of tissues) and ultimately leaf dropping.Stunted growth of plants.Lower leaves have black necrotic veinsSize and number of tubers are reduced.

Mode of spread of Potato Virus Y, PVY

Infected tubers

Secondary spread through aphid vectors

Mode of spread of Potato Virus Y, PVY

Infected tubers

Secondary spread through aphid vectors

Potato Leaf Roll Virus (PLRV)

Potato leaf roll is a destructive viral disease of potato, reducing yield and quality of tubers

SymptomsLeaflets roll upwards from the margin and progress towards the midribs until the entire lamina is involvedInfected plants are stunted and have a light yellow to pale green color.

Leaflets are thick, leathery, brittle & rattling sound when disturbed.Few tubers cluster around the stem.Tubers develop necrosis.

Mode of spread of Potato Leaf Roll Virus

(PLRV)

Infected tubers

Spread by Aphid vectors

Mode of spread of Potato Leaf Roll Virus

(PLRV)

Infected tubers

Spread by Aphid vectors

Obtain certified seeds from a reliable source and plant early in the season

Rouge out infected plants as soon as detected in the field.

Dehulming should be done when aphid population starts building up and then leave the tuber in the soil to mature. Control of aphid vectors: Using systemic insecticides at planting eg. Dimethoate @ 1ml/lit.

Management of potato virus diseases