RESEARCH NOTE/NOTA INVESTIGATIVA DETECTION OF PLANT-PARASITIC NEMATODE DNA IN THE GUT OF PREDATORY AND OMNIVOROUS NEMATODES

Cabos, R. Y. M., K.-H. Wang, B. S. Sipes, W. P. Heller, and T. K. Matsumoto. 2013. Detection of plant-parasitic nematode DNA in the gut of predatory and omnivorous nematodes. Nematropica 43:44-48. A protocol for molecular gut analysis of nematodes was developed to determine if predatory and omnivorous nematodes from five different guilds prey on Rotylenchulus reniformis, Meloidogyne incognita, and Radopholus similis. Mononchoides, Mononchus, Neoactinolaimus, Mesodorylaimus, and Aporcelaimellus were collected from Hawaii agroecosystems. Gut contents were released by slicing nematodes and pipetted into a PCR tube. Appropriate speciesspecific primers for the PCR reaction were determined by the predominant plant-parasitic nematodes associated with the source of the predatory and omnivorous nematodes. Predator and omnivore samples containing ingested R. reniformis, M. incognita and R. similis amplified a band of the desired size of 224, 342, and 269 bp, respectively. All predator and omnivore genera tested were positive for plant-parasitic nematode DNA in at least 22% of the specimens assayed. The highest percentage of positive detections (55%) was in Neoactinolaimus. This study confirmed that species-specific PCR primers could detect targeted plant-parasitic nematode prey in the gut of excised nematodes. This protocol could be adopted to further our understanding of the role of nematodes in soil food web interactions.