Effects of cuticle source and concentration on germination of conidia of two isolates of Nomuraea rileyi

Abstract

The effects of cuticle from larvae of Trichoplusia ni, Heliothis zea and H. virescens on rate and extent of germination of conidia of a Mississippian isolate (MS) and an Ecuadoran (EC) isolate ofNomuraea rileyi were studied. Solid substrates generally stimulated more germination than submerged substrates. There was little or no effect of cuticle source (H. zea or H. virescens) on germination of either the EC isolate or the MS isolate cultured on a solid substrate, however, differences in patterns of germination were obtained in submerged substrates. Addition of cuticle of H. zea or H. virescens generally increased the germination time for the M S isolate. Germination time for the EC isolate was significantly increased when H. virescens cuticle was used.

Cuticular fatty acids of Galleria mellonella (Lepidoptera) inhibit fungal enzymatic activities of pathogenic Conidiobolus coronatus

“…The species-specific nature of the exoskeleton seems to be a decisive factor governing the sensitivity or resistance of various insect species to fungal infection [ 5 ]. The composition of the cuticle strongly influences conidial adherence and germination, resulting in the susceptibility to a fungal pathogen varying between species [ 4 , 6 , 7 , 8 ].…”

Bioassay and enzymatic comparison of six entomopathogenic fungal isolates for virulence or toxicity against green peach aphids Myzus persicae

“…Insect pathogenic fungi infect insects by breaching the host cuticle composed of chitin fibrils embedded in a matrix of proteins, lipids, pigments and Nacylcatecholamines (Richard et al, 2010). The cuticle composition strongly influences conidial germination, resulting in the differential susceptibility of various insect species to a fungal Pathogen (Boucias and Latge, 1988;El-Sayed et al, 1991;Wang et al, 2005). They secrete extracellular enzymes proteases, chitinases and lipases to degrade the major constituents of the cuticle (that is, protein, chitin and lipids) and allow hyphal penetration (Wang et al, 2005;Cho et al, 2006).…”

The cuticular fatty acids of Calliphora vicina, Dendrolimus pini and Galleria mellonella larvae and their role in resistance to fungal infection

“…Susceptibility or resistance of various insect species to fungal invasion may result from several factors, including differences in the structure and composition of the exoskeleton, the presence of antifungal compounds in the cuticle, as well as the efficiency of cellular and humoral defense reactions of invaded insect (Vilcinskas and Gö tz, 1999). The cuticle composition strongly influences conidia germination, resulting in the differential susceptibility of various insect species to a fungal pathogen (Boucias and Latge, 1988;El-Sayed et al, 1991;Wang et al, 2005). The nature of the inductive triggers has not been determined, but while the protein and chitin composition of the insect procuticle appears similar in all insects, the epicuticular components are extremely heterogeneous and therefore have the potential to lead to different pathogen responses in particular insects (Thompson, 1973;Wang et al, 2005).…”