Effect of carbohydrate type and concentration on polyhydroxy alcohol and trehalose content of conidia of three entomopathogenic fungi Hallsworth, John E. and Magan, Naresh,, 140, 2705-2713 (1994), doi = https://doi.org/10.1099/00221287-140-10-2705, publicationName = Microbiology Society, issn = 1350-0872, abstract= The entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliaeand Paecilomyces farinosuswere cultured on solid agar media containing different carbohydrate components (glycerol, glucose, trehalose or starch) at concentrations of ≤ 142.7 g added carbon I-1for 30 d at 25 °C. The water activity (aw) of the media ranged from 0.925 to 0.998. Growth of M. anisopliaeand P. farinosuswas stimulated between 0.975 and 0.995 awon glucose media and that of P. farinosusat 0.975 awon glycerol media. At < 0.970 aw’growth of each fungal species was significantly reduced (P< 0.05). Polyhydroxy alcohols (polyols) and trehalose were extracted from conidia produced on different media and quantified using HPLC. Total polyol content of conidia produced on glucose media varied between 5.2 and 52.2 mg g-1for B. bassiana, 77.3 and 90.3 mg g-1for M. anisopliae, and 26.7 and 76.1 mg g-1for P. farinosus.The amounts of specific polyols in conidia varied significantly from media of different glucose concentrations. Mannitol was the predominant polyol in conidia of all three species, with conidia of M. anisopliae, for example, containing as much as 75.2 mg mannitol g-1when cultured on glucose media. The amount of the lower molecular mass polyols glycerol and erythritol was greater in conidia produced on glucose media with > 50.0 g added carbon I-1than that in conidia produced at lower glucose concentrations. Conidia contained between 10.8 and 20.8 mg glycerol plus erythritol g-1on glucose media with 142.7 g added carbon I-1, depending on species. Conversely, conidia of B. bassianaand P. farinosuscontained maximum amounts of trehalose (≤ 23.5 mg g-1) when produced on glucose media with < 50.0 g added carbon I-1and trehalose content was considerably less at higher glucose concentrations. There were accumulations of glycerol and erythritol in conidia of all three species when grown on glycerol media with > 25.0 g added carbon I-1, conidia of B. bassianacontained up to 154.0 mg glycerol plus erythritol g-1. When B. bassianaand P. farinosuswere grown on trehalose media, conidia contained up to 222.1 mg trehalose g-1. By contrast, conidia of M. anisopliaecontained < 17.0 mg trehalose g-1under all conditions tested. The water availability of solutions of different polyols is discussed in relation to their potential to act in osmotic adjustment during germination. The ability to manipulate polyol and trehalose content of fungal propagules may be critical in enhancing the storage life and efficacy of biological control agents., language=, type=