Research Papers: Effect of Meloidogyne incognita and M. javanica on the Growth of Two Flue-Cured Tobacco Cultivars

Abstract

Greenhouse studies were carried out to evaluate the effect of three Meloidogyne incognita and one M. javanica populations on the growth of the flue-cured tobacco cultivars "Hicks Broadleaf" and "NC-95", susceptible and resistant respectively to M. incognita. Significant differencies were found among populations and between them and the uninoculated controls in the number and green weight of leaves, as well as the height and green weight of stems. However, none of the populations caused consistently more damage than the others. In "NC-95", the reductions in growth caused by the three M. incognita populations, which did not cause formation of galls on the roots or reproduced, was often more pronounced than those caused by a population of M. javanica which readily reproduced and formed root-knots on this cultivar. Reproduction of the four root-knot nematode populations was greater during spring than during fall, when average soil temperature was 6 C lower (24 C vs 18 C.)