Research Papers: Estudio de Resistencia a Meloidogyne incognita en Variedades de Tabaco "Flue Cured"

Resumo

A study on the resistance of twenty five tobacco (Nicotiana tabacum L.) varieties to the root-knot nematode, Meloidogyne incognita (Kofoid and White) Chitwood was performed under greenhouse conditions at the Agrarian University La Molina, Lima, Peru (252 m.a.s.l.). Tobacco plants were grown in nematode infested and non-infested soil in square boxes. The average air temperature was 28C. Data on root gall index, plant height, number of leaves per plant and nematode population density in the soil were determined at 45, 75, and 105 days after planting. Nematode identification was also effected to confirm the species. Susceptible varieties showed no tolerance to the root-knot nematode as indicated by reduced plant height. The number of leaves per plant was also significantly reduced. Some varieties evaluated as resistant showed increases in the number of leaves. The flue cured tobacco varieties which showed the best resistance and tolerance to M. incognita were: Cocker 254, Cocker 258, Co