Correlation of Tobacco Yield,Value, and Root-Knot Index with Early-to-Midseason,and Postharvest Meloidogyne Population Densities

Certain nematicidal treatments for the control of root knot of tobacco in six field experiments in North Carolina were used to determine early, midseason, and postharvest densities of eggs and larvae of Meloidogyne spp., postharvest root-knot indices, and crop yield and value. Various statistical correlations showed that population densities determined 6-8 wk after transplanting were more indicative of treatment effectiveness than postharvest densities. Logarithmic transformation of early and midseason population data stabilized the variance.