Positive PCR but no active growing Neopestalotiopsis
When strawberry plants start to wilt, it’s easy to point the finger at Neopestalotiopsis. Especially when PCR results come back positive. But let’s take a moment to understand what that actually means. PCR confirms the presence of DNA, not necessarily a living, active fungus. So yes, Neopestalotiopsis might be there – or it was there – but it’s not the whole story.
Plating Neopestalotiopsis
When we plate these plants, we often see a much more complex picture. Multiple pathogens show up: Fusarium spp., Colletotrichum, Cylindrocarpon, Phytophthora, and Neopestalotiopsis. In other words, this is not a single-pathogen issue. We’re dealing with a disease complex – and more importantly, a root rot – above ground disease complex.
Focusing only on leaf infections caused by Neopestalotiopsis could lead you to overlook the more serious threat lurking below ground. Root rot quietly wipes out your plants, and by the time it becomes visible, it’s often too late.
Going heavy on fungicides might seem like a quick fix, but be careful, this can backfire. Overapplication leads to extra plant stress, and stressed plants are more vulnerable to root pathogens. Plants can’t fight on two fronts at once. If all their energy goes into managing chemical stress and foliar infections, the roots become an easy target.
I have been analysing plants in the Netherlands as well as Canada. They tell the same story. We have a disease complex, not just Neo-P.