Meloidogyne enterolobii egg extraction in NaOCl versus infectivity of inoculum on cucumber

Abstract

Extraction of eggs of Meloidogyne spp. in sodium hypochlorite (NaOCl) is a helpful procedure to assess the population levels and to obtain inoculum. In this sense, laboratory and greenhouse experiments were done to evaluate the effect of the NaOCl concentration on the viability of M. enterolobii eggs. Additionally, the objective of this investigation was to corroborate the preferable treatments to count populations in cucumber galled roots or to obtain inoculum of M. enterolobii. It was shown that the effect of the NaOCl concentration on the viability of M. enterolobii eggs is potentially detrimental. The NaOCl concentration caused a higher hatching, which in turn, resulted in non-infective larvae. Therefore, the best treatments to obtain inoculum of eggs of M. enterolobii included the 0.75% NaOCl (with 8-min stirring), 0.5% NaOCl (with stirring for 8, 12, and 16 min), and 0.3% NaOCl concentration (with stirring for 8, 12, 16, and 20 min). For a correct estimate of the egg population in roots, we show by several treatments that a concentration of 0.5% NaOCl (with stirring for 8, 12, and 16 min) and 0.75% NaOCl (with 8-min stirring) give the highest results.