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Entomopathogenic fungi (EPF) infect insects and are of interest for understanding host-pathogen interactions and biological control of insect pests. The fruit fly Drosophila melanogaster offers an excellent model system for exploring the biology of EPF and their interactions with insects. In this review, we describe the advantages of using D. melanogaster as a model system to study EPF and highlight EPF of relevance to agriculture. We also propose possible directions for future research in this area. We predict that in the future, D. melanogaster will continue to be a productive system for understanding the biology of the fungi attacking insects and will no doubt contribute to the future of biological control, conservation and other areas. [ABSTRACT FROM AUTHOR]

Abstract: Sea fan aspergillosis, first reported in the Caribbean in the 1990s, is one of the best-characterized coral diseases. The disease is named after Aspergillus sydowii, which was proposed as the sole pathogen. Here, inoculation of healthy fans in aquaria with A. sydowii failed to induce purpling and tissue necrosis, the characteristic signs of aspergillosis. Grafting experiments in situ, using diseased and healthy tissues, failed to induce permanent purpling in most cases, suggesting that fans have developed resistance to aspergillosis. The temporary purpling is likely a non-self-recognition response and not an exclusive criterion to diagnose aspergillosis. For the first time, we quantified fungal biomass in fans demonstrating that ergosterol concentration in healthy tissues was generally higher than that in the diseased tissues, contrary to our expectations for a fungal-induced disease. These results suggest that there are still considerable gaps in our understanding of aspergillosis, coral-associated fungal communities and coral non-self-recognition responses. [Copyright &y& Elsevier]

Abstract: Most fungal species from marine environments also live on land. It is not clear whether these fungi reach the sea from terrestrial sources as spores or other propagules, or if there are separate ecotypes that live and reproduce in the sea. The emergence of marine diseases has created an urgency to understand the distribution of these fungi. Aspergillus flavus is ubiquitous in both terrestrial and marine environments. This species is an opportunistic pathogen in many hosts, making it a good model to study the relationship between genetic diversity and specificity of marine fungi. In this study, an intraspecific phylogeny of A. flavus isolates based on Amplified Fragment Length Polymorphisms (AFLPs) was used to determine if terrestrial and marine isolates form discrete populations, and to determine if phylogeny predicts substratum specificity. Results suggest lack of population structure in A. flavus. All isolates may compose a single population, with no clade particular to marine environments. [ABSTRACT FROM AUTHOR]

Aspergilloses are opportunistic infections in animals and humans caused by several Aspergillus species, including Aspergillus flavus. Although the immune system of Drosophila melanogaster is extensively studied, little is known about the fly's specific responses to infection by A. flavus. We compared gene expression levels during induced infections in D. melanogaster by a virulent A. flavus isolate and a less virulent isolate, as well as from uninfected flies as a control. We found that 1081 of the 14,554 gene regions detected were significantly differentially expressed among treatments. Some of these up- and down- regulated genes were previously shown to be involved in defense responses against pathogens. Some are known to be involved in vitelline membrane formation in flies. Other up- and down-regulated genes are of unknown function. Understanding expression of these genes during the process of infection in flies should improve our knowledge of innate immunity in invertebrates, and by extension, in vertebrates as well. • This study provides a comparative transcriptomic data concerning Drosophila melanogaster infected with Aspergillus flavus. • 1081 transcripts were differentially expressed on infected and not infected D. melanogaster. • Expressed genes were involved in defense responses to virus, bacteria, fungi, and diseases. • Data will be of great value for understanding host immune defense against aspergillosis. [ABSTRACT FROM AUTHOR]

Graphical abstract Healthy, defoliated and fallen coffee plants in Puerto Rico after Hurricane Maria. Error bars show +1 s.e. Highlights • Impact of Hurricanes Irma and Maria in 2017 on coffee plants in Puerto Rico was surveyed. • Damage to plants was less than predicted: 64% healthy, 16% defoliated and 20% fallen. • Damage varied greatly among sites. • Orientation was related to damage; altitude, distance from the storm, precipitation and wind gust speed were not. • Coffee berry borer populations decreased after the hurricanes but recovered quickly. Abstract Hurricanes Irma and Maria hit Puerto Rico in September 2017. According to initial estimates, 90% of coffee plants were destroyed. We surveyed damage to coffee plants in 81 plots throughout the coffee-growing area of west-central Puerto Rico; we used the change in the Landsat derived Normalized Difference Vegetation Index (ΔNDVI) to estimate damage to vegetation in coffee farms. ΔNDVI values ranged from 0 to 0.36. Almost half of all plots had ΔNDVI ≤ 0.17 and had less than 20% damaged plants, whereas twelve plots in six municipalities were severely hit and had ≥80% plants damaged. Damage varied greatly among plots and even within plots. Probability of damage was significantly higher in sites with north- and south-facing slopes than in sites with east- and west-facing slopes. Neither minimum distance from the center of Hurricane Maria, altitude, precipitation nor maximum wind speeds were related to extent of damage. Coffee berry borer ( Hypothenemus hampei ) populations decreased after the hurricanes but recovered quickly. Understanding patterns of damage and their causes may help suggest ways to protect the coffee industry from future natural disasters. [ABSTRACT FROM AUTHOR]

Sessile organisms such as octocorals cannot avoid threats such as predation, parasitism or fungal infections through evasive responses. Instead, they rely on strategies that deter or reduce the impact of these threats. One such strategy is the development of hard structures such as sclerites, which are minute calcium carbonate skeletal elements located on top of the ectoderm and within the mesoglea and gastrodermal tube walls. Sclerites have multiple roles, including structural support of the colony and protection from predators. The role of sclerites as a physical barrier that deters fungal infection, however, is unknown. This study examines the potential role of sea fan sclerites as protection from fungal infection. To accomplish this, four different fungi isolated from healthy sea fans were inoculated into 5 mL tubes filled with culture media and with sclerites from healthy and diseased fans placed on top. To determine whether chemical compounds in the sclerites impact infection, sclerites from healthy and diseased fans were extracted for several days with acetone prior to inoculation. Results showed that the sclerite layer delayed fungal infection from reaching the agar when compared to controls (tubes with agar but no sclerites). There was no difference between tubes with healthy and diseased sclerites, but there were differences among sclerites extracted with acetone. This study suggests that, in addition to the roles in structural support and predator deterrence, sclerites play a role as physical and chemical barriers against to fungal infection. [ABSTRACT FROM AUTHOR]

Sun and shade coffee ( Coffea arabica L.) provide different biotic and abiotic environments which can affect the damage, distribution and reproduction of coffee pests. However, the effect of shade on damage by the coffee berry borer (CBB) Hypothenemus hampei (Ferrari), the most important coffee pest worldwide, is controversial and unclear. We compared infestation, total population per fruit and sex ratio of the CBB between shade and sun coffee, during two coffee-growing seasons in Adjuntas, Puerto Rico. According to generalized linear mixed models, CBB infestation was significantly higher in shade plots, and ranged from 7–52% compared with 4–26% in sun. However, the total population per fruit was higher in sun coffee fruits than in shade coffee, and the sex ratio was more biased to females in sun coffee. Sun coffee was characterized by higher temperatures and lower relative humidity. Environmental variables appeared to be important drivers of CBB population densities in field, with positive correlations between temperature and the number of pupae, juveniles, females and males. This tendency of larger populations in sun plots could represent a serious threat for coffee. In addition to fewer CBB in infested fruits in shade plots, we observed that shade coffee also had more natural enemies of CBB such as ants and entomopathogenic fungi. [ABSTRACT FROM AUTHOR]

Abstract: Aspergillus flavus is one of the most common fungal eukaryotes on the planet. It is notorious for production of aflatoxins, for causing aspergillosis in humans and animals, and as an opportunistic pathogen of animals and plants. Its role in marine habitats is unclear. Until now, little phylogeographic structure has been detected for the species, except at very local scales, and it appears to fit the classic dictum of microbial biogeography: Everything is everywhere. Here we use genetic relationships among isolates to determine phylogeographic structure, mating types, and differences in preferences for: marine vs. terrestrial habitats, various substrates, and clinical vs. nonclinical environments. Phylogenetic relationships among isolates were estimated using amplified fragment length polymorphisms (AFLPs) and mating types were determined for a worldwide sample of A. flavus isolates from diverse substrates and geographic locations. All isolates composed a single population, with no significant differentiation of marine vs. terrestrial isolates, clinical vs. environmental isolates, or association with substrate or geographic origin. There was evidence for local dominance of a single clade, probably clonal in origin and short-lived. The proportion of mating types was 1:1, supporting the hypothesis of recombination in natural populations. However, a high proportion of clinical isolates were MAT1-1 (85%), suggesting that a gene linked to the MAT1-1 idiomorph could play a role in pathogenicity. This study suggests that a more appropriate description of the phylogeography of A. flavus is ‘everything is everywhere, but not all the time.’ [Copyright &y& Elsevier]