Effect of culture filtrates of Pseudomonas striata, Trichoderma harzianum, T. viride and Aspergillus awamori on egg hatch of Meloidogyne javanica uri icon

abstract

  • The root-knot nematode, Meloidogyne javanica, is an important parasite of field crops in the tropics. To develop eco-friendly management options for this nematode, culture filtrates of Pseudomonas striata (strain 303), Aspergillus awamori, Trichoderma harzianum OPT NAB and T. viride were screened for their effects on egg-hatch in laboratory experiments. Five egg masses of M. javanica approximately the same size and colour were transferred in 5 ml of culture filtrates in 2.5-cm diameter Petri dishes and incubated at 25°C. Filtrates of non-inoculated nutrient broth, potato dextrose broth and distilled water were used as negative controls. The number of hatched second-stage juveniles in 5 replications for each treatment was determined after 7 and 14 days. Results suggest that culture filtrates of P. striata strain 303 were the most effective in reducing egg hatch of M. javanica by up to 95% compared with controls, whereas culture filtrates from A. awamori, T. harzianum and T. viride reduced egg hatch by 13 to 69%. The inhibitory effect on egg hatch of the organisms tested was reversible, except that of P. striata strain 303, by transferring the eggs to distilled water. The results indicated that culture filtrate of P. striata 303 is lethal for M. javanica eggs and may be considered in a nematode management strategy

publication date

  • 2002