Effects Of Cold Temperatures On Disease

Nathan Kleczewski Ph.D

We have experienced exceptionally cold temperatures in Delaware this Winter.  The main issue most growers are concerned with at this point is the impact on wheat or barley stands, particularly in late planted fields.  What about the impacts of these temperatures on field crop diseases?

It is difficult to say for certain what impact these temperatures will have on field crop diseases.  However, I speculate that it likely will negatively impact several pathogens that we saw during the rainy 2013 growing season, especially those that prefer warmer temperatures.  In particular, the deep cold throughout the region will likely push the rusts further south, which may impact when initial infections occur on our crops.  Frogeye leaf spot, which prefers warmer temperatures may also be negatively impacted.   The cold temperatures may also impact overwintering potential of late blight in potatoes that may originate from cull piles or weeds.  This does not mean that we will not have issues with these diseases in 2014, but the primary inoculum for some pathogens may be negatively affected.

Source : udel.edu