Review of Pasteuria penetrans: Biology, ecology, and biological control potential

Pasteuria penetrans is a mycelial, endospore-forming, bacterial parasite th at has shown great potential as a biological control agent of root-knot nem atodes. Considerable progress has been made during the last 10 years in und erstanding its biology and importance as an agent capable of effectively su ppressing root-knot nematodes in field soil. The objective of this review i s to summarize the current knowledge of the biology, ecology, and biologica l control potential of P. penetrans and other Pasteuria members. Pasteuria spp. are distributed worldwide and have been reported from 323 nematode spe cies belonging to 116 genera of free-living, predatory, plant-parasitic, an d entomopathogenic nematodes. Artificial cultivation of P. penetrans has me t with limited success; large-scale production of endospores depends on in vivo cultivation. Temperature affects endospore attachment, germination, pa thogenesis, and completion of the life cycle in the nematode pseudocoelom. The biological control potential of Pasteuria spp. have been demonstrated o n 20 crops; host nematodes include Belonolaimus longicaudatus, Heterodera s pp., Meloidogyne spp., and Xiphinema diversicaudatum. Pasteuria penetrans p lays an important role in some suppressive soils. The efficacy of the bacte rium as a biological control agent has been examined. Approximately 100,000 endospores/g of soil provided immediate control of the peanut root-knot ne matode, whereas 1,000 and 5,000 endospores/g of soil each amplified in the host nematode and became suppressive after 3 years.