Differences in free fatty acids (FFAs) chemical composition of insects may be responsible for susceptibility or resistance to fungal infection. Determination of FFAs found in cuticular lipids can effectively contribute to the knowledge concerning insect defense mechanisms. In this study, we have evaluated the susceptibility of three species of cockroaches to the entomopathogenic fungi Metarhizium anisopliae (Metschnikoff) Sorokin by topical application. Mortality due to M. anisopliae was highly significant on adults and nymphs of Blattella germanica L. (Blattodea: Blattellidae). However, mortality was faster in adults than in nymphs. Adults of Blatta orientalis L. (Blattodea: Blattidae) were not susceptible to the fungus, and nymphs of Blaptica dubia Serville (Blattodea: Blaberidae) were more susceptible to the fungus than adults. The composition of cuticular FFAs in the three species of cockroaches was also studied. The analysis indicated that all of the fatty acids were mostly straight-chain, long-chain, saturated or unsaturated. Cuticular lipids of three species of cockroaches contained 19 FFAs, ranging from C_14:0 to C_24:0. The predominant fatty acids found in the three studied species of cockroaches were oleic, linoleic, palmitic, and stearic acid. Only in adults of Bl. orientalis, myristoleic acid, γ-linolenic acid, arachidic acid, dihomolinoleic acid, and behenic acid were identified. Lignoceric acid was detected only in nymphs of Bl. orientalis. Heneicosylic acid and docosahexaenoic acid were identified in adults of Ba. dubia.

Insect repellent textiles are currently being investigated as a complementary tool to control disease vectors, such as mosquitoes. The application of microencapsulated biopesticides to textiles is a promising low-toxicity alternative to other control methods, as microcapsules may prolong the release of the repellent agent. In this work, microcapsules containing two biopesticides, namely citronella essential oil and citriodiol® were prepared and applied to cotton textiles using a variety of techniques. The aim of this work was to evaluate these functional textiles to select the most efficient, durable systems. Citriodiol-treated cotton presented a prolonged durability, and 100% repellency could be achieved for more than 30 days after padding onto cotton fabrics. It has to be pointed out that all these repellent textiles have been obtained by scalable, low-cost methods which would require no additional investment for textile finishing industries.

Filamentous fungi of the genera Lecanicillium and Akanthomyces (Ascomycota: Hypocreales: Cordycipitaceae) have been isolated from a variety of insect orders and are of particular interest as biological control agents for phloem-sucking plant pests. Three aphid- and whitefly-pathogenic fungal strains that had been isolated from naturally infected Trialeurodes vaporariorum and Myzus persicae in Argentina were assigned to the species Lecanicillium uredinophilum by combined analyses of morphology and ITS, LSU, EF1A, RPB1 and RPB2-based molecular taxonomy, giving rise to both the first description of this fungus from hemipteran insects and its first report from outside South-East Asia, especially from the American continent. A combination of phylogenetic reconstruction and analysis of pair-wise sequence similarities demonstrated that—reflecting recent changes in the systematics of Cordycipitaceae—the entire species L. uredinophilum should be transferred to the genus Akanthomyces. Consequently, the introduction of a new taxon, Akanthomaces uredinophilus comb. nov., was proposed. Moreover, extensive data mining for cryptic A. uredinophilus sequences revealed that (i) the fungus is geographically widely distributed, including earlier unrecognized isolations from further American countries such as the USA, Mexico, and Colombia, and (ii) entomopathogenic and mycoparasitic lifestyles are predominant in this species.

The aim of the present review is to summarize the current knowledge about Leptolegnia chapmanii as a pathogen of mosquito larvae. To this end, we present data on its identification, distribution, host range and effects on non-target organisms, effects of environmental factors, in vitro growth, release and persistence in anthropic environments, and effect combined with other insecticides. The data presented allow confirming its potential as a biocontrol agent.