Submitted to: Nematropica
Publication Type: Abstract Only
Publication Acceptance Date: 10/20/2005
Publication Date: 12/1/2005
Citation: Kariuki, G.M., Brito, J.A., Kaur, R., Nyczepir, A.P., Dickson, D.W. 2005. Attachment of isolates of pasteuria penetrans to meloidogyne floridensis [abstract]. Nematropica. 35:79. Interpretive Summary: The Peach Root-Knot nematode, Meloidogyne floridensis, was redescribed from peach originally collected from Gainesville, Florida, United States. In greenhouse tests, the newly released Guardian peach rootstock, tomato and watermelon were good hosts; cotton was a poor host; tobacco, pepper and peanut were nonhosts. This nematode is of special interest to the peach industry in the Southeast, since it infects and reproduces on Meloidogyne resistant peach rootstocks. Finding an alternative to chemical control of this root-knot nematode species needs to be investigated. In 2004-05, the biocontrol agent Pasteuria penetrans isolates P20, PP1, and B4 were evaluated for their ability to attach to second-stage juvenile of two different isolates of the Peach Root-Knot Nematode (Mf1 and Mf2). Results indicate that the B4 isolate attached to both nematode isolates, showing 97% to 98% attachment rate to Mf1 and Mf2, respectively. These data provide useful insights into the use of Pasteuria penetrans (B4-isolate) as a potential biocontrol agent to manage the Peach Root-Knot Nematode in peach and vegetable industries in the Southeast.
Technical Abstract: Meloidogyne floridensis is a newly described root-knot nematode species that infects and reproduces on Meloidogyne resistant peach rootstocks. This nematode has been reported on cucumber, eggplant, tomato, snap bean, the lilac tasselflower in several Florida counties. There has been no report on Pasteuria spp. attaching and infecting M. floridensis. Pasteuria penetrans isolates P20, PP1, and B4 were tested for their ability to attach to second-stage juvenile (J2) of two different isolates of M. floridensis (Mf1 and Mf2). M. arenaria race 1 and M. javanica were used as controls. B4 attached to both M. floridensis isolates with a mean number of endospore per J2 of 24 and 19 for Mf1 and Mf2, respectively. PP1 attached with a mean number of 13 endospores per J2 for each nematode isolate. P20 showed a lower compatibility to Mf1 than to Mf2, with only 0.6 and 4 endospore attached per J2, respectively. B4 showed a 97% to 98% attachment rate to Mf1 and Mf2, respectively. These results demonstrate that B4 is a potential biocontrol agent for M. floridensis. Ongoing studies are underway to determine whether B4 and PP1 infect and develop in M. floridensis.