Pre-parasitic second-stage juveniles (pre-J2s) of Meloidogyne graminicola are non-feeding in soil, and their migration, localization and successful invasion of host roots are essential for survival. Chemotaxis is thought to play a central role in host localization, but the mechanisms of chemotaxis are poorly understood. In this study, we cloned and evaluated the molecular characteristics and functions of four chemosensory genes, including Mg-odr-3, Mg-odr-1, Mg-tax-4, and Mg-osm-9. Quantitative real-time PCR (qRT-PCR) analysis revealed that Mg-odr-3 and Mg-osm-9 tended to be expressed in pre-J...
