Field Evaluation of Susceptibility to Meloidogyne arenaria in Arachis hypogaea Plant Introductions

Resistance to Meloidogyne arenaria race 1 is not currently available in commercial peanut cultivars. Moderate levels of resistance have been identified in Arachis hypogaea plant introductions (PI) in previous greenhouse studies. The purpose of this work was to evaluate the effects of resistance in peanut PI on populations dynamics of M. arenaria in field plots. The PI designated as resistant in greenhouse studies had fewer M. arenaria in roots than the most susceptible PI. At midseason and at the end of the season, resistant PI had fewer M. arenaria in rhizosphere soil than the most susceptible PI. Seven resistant PI had lower numbers of M. arenaria than 'Florunner' at the end of the growing season. Gall index, egg mass index, number of eggs/plant, and number of eggs/g root from greenhouse screening were highly correlated with population levels of M. arenaria in the field, especially at midseason. These greenhouse indices should provide reliable estimates of host suitability in future studies.