Pythium and Phytopythium species associated with weeds collected in vegetable production fields in Brazil

Abstract

Significance and Impact of the Study: The presence of weeds in cultivated areas is a limitation on vegetable production in Brazil. Beyond their competition for water, nutrients and light, weeds may be alternative hosts of plant pathogens, favouring their survival and potential increase in population. In this work, six Pythium and two Phytopythium species were identified infecting weeds collected from vegetable fields in Brazil. Most of these Pythium and Phytopythium species identified are polyphagous plant pathogens, attacking many plant species including many vegetables. This finding has ecological and epidemiological significance indicating weeds can be reservoirs and inoculum sources of pathogens for vegetable crops.