Speaker
Description
Plant-parasitic nematodes cause major economic losses worldwide by infecting crops, diverting resources and impairing plant growth. While resistance aims to reduce parasite burden, tolerance allows plants to maintain yield despite infection, offering a complementary and potentially more sustainable strategy. Understanding how tolerance arises requires mechanistic insights into host-parasite interactions and their constraints.
We developed a mathematical model describing the coupled dynamics of plant growth, internal resource allocation and nematode population processes. The model incorporates key biological mechanisms, including resource-dependent plant development, nematode infection and reproduction, and feedbacks between resource limitation and parasitism. We analytically derived the basic reproduction number and identified equilibrium states: extinction, healthy plant and plant-nematode coexistence. We showed that coexistence strongly depends on plant resources, highlighting conditions under which tolerance can emerge. In addition, we numerically explored how variations in plant and nematode parameters affect tolerance over a cropping season. Our study highlighted the dual role of resource production: higher production increases plant growth but also promotes nematode proliferation. A compromise therefore emerges between promoting productive plants and limiting yield losses under infestation, shaped by nematode virulence and plant quantitative resistance.
