Blight, slugs and weather threaten potato crop


The potato harvest is under a three-pronged attack which could lead to a shortage of home produce later in the year, it emerged at the weekend.

First, the potato acreage is likely to be down by 2,000 acres this year because of continuing bad weather.

The drop in production could lead to a shortage of Irish stocks as crops have already been badly hit by blight and blackleg disease as the weather has prevented farmers spraying against these diseases.

Teagasc, the agriculture and food development authority, warned that potato blight represented the second threat to the crop and is now so widespread that in some places fields of main-crop potatoes had been ploughed out where the disease was out of control.

And a third threat was identified at the weekend when it was learned that potato crops face "a severe onslaught" of slugs from mid-July onwards because of the severe wet weather which encourages the pest.

Mr Tom Maher, national potato specialist with Teagasc, said almost 2,000 acres of the crop remained to be planted at the onset of the wet weather in May.

"The likelihood of these crops being planted now is slim. If farmers do not get an opportunity to plant over the next few weeks, they should significantly reduce the level of nitrogen fertiliser," he said.

He warned farmers that if they applied more than 125 units of nitrogen per hectare on late planted crops, the crops would mature too late and would be very prone to blight during the autumn.

He said that because of the weather conditions, blackleg disease was now a major problem in an early variety of potato, British Queens.

He said there was no chemical cure for blackleg in potatoes other than to let the crop mature and hope that the blackleg tubers would rot out.

Regular spraying, he said, was the best defence against blight but farmers should also search for blight sources, such as potato dumps and in cereal crops.

He warned that the main crop varieties, Rooster and Maris Piper, were at most risk from slug attacks later next month.

To deal with the impact of the weather, Teagasc has arranged a series of special farm walks for growers in the main growing areas to begin on July 2nd.