Conidia production and quality from entomopathogenic fungi in solid-state culture (SSC) are frequently inferred from results obtained in superficial culture (SC), however, there are no reports comparing both culture systems in similar conditions. In both systems, Isaria fumosorosea ARSEF 3002 and Isaria fumosorosea CNRCB1 were used (recently reassigned as Isaria javanica). Both systems were compared using two Isaria fumosorosea strains (ARSEF 3302 and CNRCB1) in terms of conidia production and quality, and also in sensitivity to oxidant pulses using a media with the same chemical composition (rice-oat mixture). Conidia production for both strains in SC was 6-fold higher respective to SSC in terms of conidia per grams of initial dry substrate (gds). Germination and viability did not show important differences between both culture systems, however, infectivity parameters from conidia towards Galleria mellonella larvae showed some differences between both systems. The differences in the conidia production between both systems were not explained in terms of specific area (α), however substrate availability per area (σ) affected the conidiation yields. The morphology of the substrate also explained these differences, since the oat bran may difficult the nutrient availability from endosperm, contrary to superficial morphology where substrates are ground making nutrients available for biomass and conidia production. Respirometry analyses, as indirect measurement of biomass, showed that the maximal production of CO2 per gds was obtained in SC.Oxygen pulses decreased conidia production respective to a normal atmospheric control independently of the strain, culture system or the application of 1 pulse (26%) or 2 pulses (26%x 2) every 24 hours. However, SSC resulted in a higher sensitivity to hyperoxidant pulses compared to SC. Conidia quality obtained in SC in both strains exhibited an increase in viability after oxidant treatments respective to atmospheric control, contrary to SSC with oxidant pulses, which did not improve viability. The infectivity in SC and SSC with oxidant pulses did not show consistent differences in infectivity parameters compared to atmospheric counterparts. In addition to the higher sensitivity to oxidant treatments, SSC with oxygen pulses presented a lower substrate invasion, probably by an insufficiency of oxygen, as consequence of differences in substrate quantity in both systems which was 15-fold higher in SSC respective to SC. Residual oxygen in oxidant treatments were determined, in SC remained between 10 to 20% during culture time, regardless if one or two daily oxygen pulses were applied, in contrast in SSC residual oxygen was close to 0%. The accumulation of CO2 in oxidant treatments behaved inversely to oxygen levels, since SC accumulated less CO2 than SSC.When initial substrate amount was equated (1 gds per experimental unit), conidiation in SC remained lower under oxidant pulses compared to normal atmosphere, however, in SSC conidia production increased with oxidant pulses for both stra...

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