Major potato producing state West Bengal is in the grip of blight disease and farmers are set to suffer huge losses this time due to the late attack of the fungi.

According to officials, the production in the state is set to fall by around 30 per cent this year despite an increase in acreage under cultivation.

The state, with the highest productivity of potato and second highest area under cultivation, has brought four lakh acres under cultivation this year. But the disease has affected almost 85 per cent of the area under cultivation.

The disease is caused by water mould or fungi active in wet weather conditions with moderate temperatures and high humidity.

The target for this year's potato production was set at 85 lakh (8.5 million) tonnes, as last year was good for potato producers. After the disease damage, the state is to produce around 65 lakh (6.5 million) tonnes only.

West Bengal's potato consumption is around 45 lakh (4.5 million) tonnes, and the rest of the production is sent to parts of Assam, Bihar, Andhra Pradesh, Orissa and Tripura. Some quantity, comprising mainly of the 'Jyoti' variety, is sent to Madhya Pradesh and Bangalore.

Meanwhile, a section of farmers has started storing inferior quality potatoes, said an agricultural marketing department official. Some of the cold storage owners have loaded more than 200,000 tonnes of 'Pokhraj' and 'S6' varieties. Water content in these two varieties is high which makes storage difficult.

Moreover, 'Pokhraj' and 'S6' varieties are also affected by the blight disease, which could damage the produce even in a cold storage.