Gene Expression Changes Induced by Reniform Nematode Infection in Cotton Roots

Host resistance to the Reniform Nematode (RN), Rotylenchulus reniformis Lindford and Oliveira, has been identified in diploid cottons Gossypium arboreum, G. herbaceum, and G. longicalyx (Stewart and Robbins, 1 ). Histological studies have identified two possible mechanisms of resistance: first, a darkened, necrotic syncytial cavity occurs (hypersensitive reaction); and second, a less frequent mechanism may occur that consists of the absence of hypertrophy of the syncytial cells. In this case the female reaches maturity but has reduced fecundity (Carter, 1 1; Agudelo et al., 00 ). The objectives of this study were to describe cotton root gene responses to reniform nematode infection in resistant and susceptible accessions, and to identify potential genes involved in feeding site formation and resistance reactions.