Nematicidal activity of Pochonia chlamydosporia blastospores and attempts to improve dehydration tolerance and storage stability with additives.

For the widespread application of Pochonia chlamydosporia as a bionematicide, cost-effective production coupled with robust stabilization processes are essential. Blastospores produced through submerged liquid fermentation yield large quantities of infective propagules in a short period. This study aimed to evaluate the nematicidal activity of P. chlamydosporia blastospores from two fungal strains against the eggs of two plant-pathogenic nematodes, as well as to assess the use of various additives to enhance their dehydration tolerance and storage stability. For the more promising strain, submerged culture yielded 1 × 109 blastospores mL-1 after 96 hours. Juvenile hatch inhibition was more pronounced with blastospores (64.8%-86.7%) than conidia (48.2%-65.3%) on Meloidogyne javanica and M. enterolobii eggs, respectively. Skim milk added to the liquid medium prior to inoculation or 72 hours after fermentation protected fungal cells from dehydration. Following dehydration, storage stability after 10 days was significantly greater at 4°C compared to 25°C. Stabilization processes to prevent cell mortality during dehydration are crucial for the development of blastospores as active ingredients in bionematicides.