Plant-parasitic nematode infections in rice: molecular and cellular insights

Being one of the major staple foods in the world, and an interesting model monocot plant, rice (Oryza sativa L.) has recently received attention from molecular nematologists studying the cellular and molecular aspects of the interaction between this crop and plant-parasitic nematodes. In this review, we highlight recent advances in this field, with a focus on the best-studied root-knot nematodes. Histological studies have revealed the cellular changes inside root-knot nematode-induced feeding sites, both in the compatible interaction with Oryza sativa and the incompatible interaction with the related species Oryza glaberrima. After comparing the published data from transcriptome analyses, mutant studies, and exogenous hormone applications, we provide a comprehensive model showing the role and interaction of plant hormone pathways in defense of this monocot crop against root nematodes, where jasmonate seems to play a key role. Finally, recent evidence indicates that effectors secreted from rice-infecting nematodes can suppress plant defense.