Author Bio

Dr. Lei Zhang is an Assistant Professor of Plant Nematology in the Department of Botany and Plant Pathology at Purdue University. He has extensive experience in both basic and applied research on plant-parasitic nematodes. His current research focuses on the diagnosis of plant-parasitic nematodes (PPNs), investigating the virulence of root-knot nematodes (RKN) in Indiana, and developing sustainable nematode management strategies using biological control agents and suppressive soils. Dr. Wenjing Guan is an Extension specialist at Purdue University, stationed Southwest Purdue Agriculture Center (SWPAC). She works with watermelon and melon growers in Southern Indiana, and smaller-scale vegetable and fruit growers across the state. Presentation: Addressing root-knot nematode challenges in high tunnel tomato production: Root-knot nematodes (RKN; Meloidogyne spp.) are among the most damaging soilborne pests affecting vegetable production, particularly in high tunnel systems where elevated soil temperatures and moisture levels favor their overwintering and population buildup. This presentation will provide an overview of root-knot nematode biology and the damage they cause in vegetables, followed by findings from a recent survey of plant-parasitic nematodes on small-scale vegetable farms across Indiana. One promising management strategy—using grafted tomato plants—will be discussed in terms of its effectiveness against RKN. However, our recent research has uncovered the emergence of virulent RKN populations in Indiana capable of overcoming the resistance conferred by tomato rootstocks. We will present evidence that strategic crop rotation involving grafted tomatoes, peppers, and potentially other vegetables can help reduce RKN pressure and slow the spread of these virulent populations. This integrated approach offers a path forward for sustainable RKN management in high tunnel vegetable systems.