Steinernema kraussei and moringa oleifera extracts can suppress meloidogyne incognita infection on tomato

Abstract

Meloidogyne incognita (Kofoid and White) Chitwood (MI) is a potential threat to tomato (Solanum lycopersicum L.) production. In this study, the inhibitory effect of Moringa oleifera L. (MO) extracts and Steinernema kraussei Steiner (SK) as stand-alone treatments and in combination was assessed to suppress the reproduction and development of MI. Highly susceptible variety of tomato cv. 'Money Maker' was tested for the invasion and development of MI. Aqueous and ethanolic MO extracts were tested in combination with SK at three different concentrations and time intervals. After 12-h 'S' concentration of aqueous MO extract + ethanolic MO extract + SK produced 100% juvenile mortality while the treatment MO + SK caused the least juvenile mortality of MI. Juvenile mortality was increased in a time-dependent manner. Aqueous MO extract + ethanolic MO extract + SK produced 100% egg hatching inhibition at standard 'S' concentration. Plant growth was significantly enhanced in plants treated with MO extracts, SK and their combinations compared to MI treated control plants. The total number of infective juveniles/g root and soil, galls, egg masses, females were highest in MI treated plants while lowest in plants treated with a combination of MI + SK + aqueous MO + ethanolic MO after 60 days of inoculation. SK and MO has demonstrated significant potential to suppress MI infection. Therefore, further investigations should focus on their efficacy at field level to prevent the infection of MI.