Report shows climate change will affect which diseases damage crops

Horticultural Week: Climate change will bring about significant changes in the spectrum of diseases that damage horticultural crops - and in the majority of cases the severity of disease outbreaks will increase. This was the finding of a report by ADAS plant pathologist Dr Peter Gladders, who was commissioned by chemical company BASF to study the impact of increasing temperatures - experts predict a rise of 2 degsC by 2050 - and more variable rainfall.

Gladders looked at how these changes would influence disease incidence and severity in seven different crops - vegetable Brassicas, carrots, lettuce, onions, potatoes, strawberries and top fruit. He studied individual diseases - identifying the optimum temperatures and wetness needs for each pathogen and so predicting where changes might occur - to find that Brassicas, carrots, lettuce and potatoes could be among the worst affected crops.

…"Heavy rainfall events and subsequent flooding would increase soil-borne diseases such as clubroot and Phytophthora root rot. We could even see new diseases emerging. Verticillium wilt and Fusarium wilts are favoured by higher soil temperatures and summer drought.

"On the bright side, we could see less downy mildew and less light leaf spot because spore production is inhibited by high summer temperatures. In carrots, many pathogens are favoured by high temperatures and high rainfall."…

Potato varieties, a chart created by FCA00000, Wikimedia Commons, under the Creative Commons Attribution ShareAlike 3.0 License