Link to home

Adaptation of the causal agent of late blight, Phytophthora infestans, to climate change

Angie Cordoba: Universidad de los Andes

<div><em>Phytophthora infestans, </em>is the causal agent of late blight disease of potatoes and tomatoes. This pathogen is highly dependent on environmental factors such as temperature and relative humidity to fully develop its life cycle. Due to climate change, patterns in the development of plant diseases are expected to occur. Previous studies have investigated the effect of temperature on the rate of sporangial germination, the development of the infection, and mycelial growth. However, the effect relative humidity variation on the pathogen’s life cycle has been scarcely studied. Here, we investigated the effect of temperature and relative humidity on growth and disease progression of isolates of <em>P. infestans</em> to assess the adaptability of this pathogen under different climate change scenarios. The <em>in vitro</em> biomass production was evaluated at five temperatures (5, 10, 15, 20, and 25 ° C) and a relative humidity of 100%. The <em>in vivo</em> lesion area and production of sporangia were assessed by means of detached-leaf assays under the same five temperatures and a relative humidity of 100%. Lastly, both <em>in vitro </em>and <em>in vivo </em>assays were conducted at three different relative humidity ranges (40-50%, 60-70%, and 80-90%) at a temperature of 18 °C. This study provides further insights about <em>P. infestans</em>’ adaptability to changes in temperature and relative humidity.</div>