Temporal expression patterns of spp. sporulation genes.

Endospore-forming bacterium in the genus spp. infect multiple agriculturally significant plant parasitic nematodes and has potential as a potent biological control. Success as a biological control requires not only spore attachment to the cuticle, but sporulation and reproduction within the nematode host. Tracking and identifying spp. development is then critical to demonstrating efficacy as a biocontrol. Microscopic observations suggest spp. follows the model bacterium, , sporulation. Here, we identified homologs of sporulation regulators in spp. and characterized the temporal expression of these genes throughout the bacterium's ∼30-d lifecycle in as a means of tracking sporulation development. Detectable levels of transcripts of were present as early as 5 d after the nematodes were exposes to spp. and were relatively constant throughout the 30-d lifecycle. Transcripts to were significantly higher in the middle of the lifecycle, while the transcripts of were detectable between 15 and 25 d, nearing the end of the lifecycle. These three markers can be used to track the process of sporulation in the nematode and augment microscopic observations. Tracking sporulation of spp. is important to fully realize its potential as a biological control method as it can more readily identify successful parasitism, define host ranges, and inform in vitro growth progress.