N. Smits et al., MODELING THE PERSISTENCE OF QUIESCENT CONIDIA OF THE ENTOMOPATHOGENICHYPHOMYCETE PAECILOMYCES-FUMOSOROSEUS EXPOSED TO SOLAR-RADIATION, Biocontrol science and technology, 7(3), 1997, pp. 365-375
Persistence of conidia of the entomopathogenic fungus Paecilomyces fum
osoroseus exposed to artificial and solar radiation at a constant temp
erature was studied by monitoring the ability to germinate and to form
colonies (colony-forming units, CFUs). The photic effect of radiation
on each of these variables was modelled by a decreasing function of U
VB irradiation (in J m(-2)). Germination ability was represented by a
logistic function and viability (log CFU) by an infinitely decreasing
function. Experiments carried out under artificial conditions, at thre
e different UVB irradiances (from 0.3 to 1.6 W m(-2)), similar to thos
e observed in nature, confirmed the adequacy of the predictor variable
and of the functions chosen for describing these data. The proposed m
odels appeared to be irradiance independent. Under solar radiation, th
e models were able to describe data collected on three different summe
r days in France (48 degrees 51'N, 2 degrees 06'E). However, it took a
greater amount of solar UVB radiation to produce the same effect as t
hat achieved indoors. This could be explained by differences in radiat
ion spectra. For each model, one set of parameters was sufficient for
representing all three sets of data: this constitutes an initial valid
ation of the models proposed.