Author
OLIVEIRA, CLEMEN - Federal University Of Goias | |
GRABAU, ZANE - University Of Minnesota | |
Samac, Deborah - Debby | |
CHEN, SENYU - University Of Minnesota |
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 7/19/2015 Publication Date: 7/24/2015 Citation: Oliveira, C.J., Grabau, Z., Samac, D.A., Chen, S. 2015. Pasteuria endospore attachment to Pratylenchus species[abstract]. 54th Annual Meeting of the Society of Nematologists. East Lansing, MI. July 19-24, 2015. p. 118. Interpretive Summary: Technical Abstract: Pasteuria spp. are endospore-forming bacteria, and most of them are obligate parasites of nematodes. A number of studies have demonstrated that Pasteuria can effectively suppress nematode populations in natural fields and have promising potential as biocontrol agents. However, parasitism of nematodes by Pasteuria is generally highly species-, race-, and/or population-specific. A population of Pasteuria sp. was found on Pratylenchus sp. with a high percentage of nematodes having attached endospores in a soil sample collected from a field in Becker County in northwestern Minnesota, USA. The purpose of this study was to determine the ability of the Pasteuria population to parasitize different species and populations of Pratylenchus. Three populations (GR, WI, and PS) of Pratylenchus penetrans and one population each of Pr. zeae, Pr. hexincisus, Pr. agilis, Pr. scribneri, and Pr. brachyurus were tested for attachment of Pasteuria endospores to the nematodes. Field soil infested by Pasteuria and Pratylenchus was treated by freezing at –80 degrees C for 24 hours, presumably killing the nematodes while keeping the Pasteuria alive. The nematodes were obtained from gnotobiotic cultures on corn roots, and were added to the freeze-treated soil in vials. After 1 week of incubation at the room temperature (~23 degrees C), the mobile nematodes were recovered from the soil by incubating the soil on a screen immerged in water in a container for 24 hours, and the percentage of nematodes with attached spores were counted. Two populations (GR and WI) of Pr. penetrans had the highest percentage (55.5% and 46.5%, respectively) of individuals with attached spores, followed by Pr. zeae (26.2%). Pr. hexincisus, Pr. agilis, Pr. brachyurus, and Pr. scribneri had low percentage (1-3%) of nematodes with attached spores, while no spore was observed on the population PS of Pr. penetrans. This study demonstrated the species- and population-specificity of the Pasteuria population infecting species in the genus Pratylenchus. |