The hot weather this summer has caused a significant drop in the number of cases of blight in P.E.I. potato fields.

Marleen Clark, who diagnoses plant disease for the P.E.I. Department of Agriculture, said the province had 31 confirmed cases of blight this time last year.

So far this year, there have only been three cases - a drop of 90 per cent.

"Late blight is very weather dependent on high humidity and moderately warm temperatures -- not a high temperature -- just a moderately warm day temperature and a cool night temperature," Clark explained.

Clark said that was the case for much of last year.

"So this year I think the conditions are a little bit different for the farmers," she said.

A fact sheet from the Provincial Department of Agriculture notes the ideal conditions for a severe outbreak of the fungus would be night temperatures of 13 C, accompanied by fog, rain, or heavy dew, and then day temperatures of 16 to 24 C

The three cases this year are in western P.E.I.

Clark noted farmers need to bring samples in immediately for testing if they suspect blight, and they should also inform their neighbours.