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Megaplatypus mutatus (Chapuis) (Coleoptera: Platypodidae) is an ambrosia beetle native to South America that causes economic loss and was recently introduced to Italy, where it attacks and damages live poplar trees. Sulcatol and sulcatone are male‐produced pheromone components involved in the mating process of M. mutatus. Their relative proportions are highly variable among insects, although the temporal pattern shows that initially only sulcatol is present, and sulcatone increases with time, until they are finally both depleted. Sulcatol and sulcatone may be produced de novo by the beetles, they may be produced by fungi, or both pathways may contribute to their production. Sulcatol is stored in the males’ hindgut but sulcatone is only present in emissions, so there is an oxidation process to transform the alcohol to the ketone before or during pheromone release. It is our hypothesis that fungi associated with M. mutatus are responsible for this process. In this work, we studied a possible contribution of associated microorganisms in the conversion of sulcatol into sulcatone and its consequent role in the temporal release pattern of these sex pheromone components observed in male insects. Moreover, we inhibited the postulated enzymes involved in this pheromone conversion process – 3‐hydroxy‐3‐methyl‐glutatyl‐CoA reductase (HMGR) and P450 enzymes of a fungal strain – and added an antibiotic and a fungicide to the homogenate during sulcatol‐sulcatone conversion. Among the fungal species, particular interest was given to Graphium basitruncatum (Matsush.) Seifert & Okada (Microascales), as it is present in male but not in female exoskeletons and in insect gallery samples, suggesting a possible different role in pherome production, as the male is the pheromone‐producing sex. Several isolated strains were able to convert sulcatol to sulcatone, whereas the fungus G. basitruncatum showed the highest production of this ketone. Additionally, inhibition of P450 enzymes and HMGR from G. basitruncatum on this alcohol‐ketone conversion demonstrated that HMGR is involved in sulcatone generation using sulcatol as precursor, and that P450 enzymes are not. Finally, sulcatone production diminished significantly in homogenized tissues of male and female M. mutatus following addition of an antibiotic and a fungicide. The results suggest that fungi associated with M. mutatus are involved in pheromone production.

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This work shows the way to develop a monolithic device for the release of an active agent. Different waxes to prepare monolithic dispensers were used. Studies to characterize the release rate of the pheromone dispensers, and to determine many physicochemical properties of the active components and waxes utilized as matrices, were conducted. The advantages of using monolithic devices as an insect pheromone dispenser in order to control an insect that attacks commercial poplar plantations were demonstrated. Also, the practical application employing monolithic dispensers manufactured in this paper with the sex pheromone of the ambrosia beetle Megaplatypus mutatus (Coleoptera: Platypodidae) was verified. This forest pest is known to attack tree plantations in South America. The release rates were mainly dependent of matrix hardness and viscosity, as well as the particle size of fillers. A good performance of the formulated monolithic dispensers was observed during the field trials, with a reduction of damage levels of 40%.

Considering that rhizospheric microorganisms play a critical role in providing the plant nutrients for growth and in the adaptation of plants to ecosystems, the aim of the present study was to evaluate the association between foliar endophytes and their effect on soil and rhizospheric fungi using Jatropha curcas, a promising crop for high-quality biofuel, as a model plant. We conducted a factorial experiment. Endophytes and selected rhizospheric fungi were isolated and identified, and the colonization of mycorrhizal fungi was recorded. While the most interesting result was the significant increase in mycorrhizal colonization when J. curcas was associated with endophytes, it was also evident that this association is able to modulate some soil chemical parameters. This study suggests that the association between J. curcas and endophytes has an impact on specific root symbiotic fungi that usually plays relevant roles in nutrient availability for plants, and it would provide tools to enhance plant growth and oil yields.

Highlights• There were no significant effects of host plant and location on fungal richness.• Two fungal species, belonging to Fusarium and Candida genera, were present in all the studied associations.• Results suggest that host plant identity would not be crucial to determine the composition of fungal communities associated to Megaplatypus mutatus. AbstractMegaplatypus mutatus is a major forest pest in Argentina and an emerging pest in Europe. In this study the multitrophic interactions between M. mutatus and associated fungi were assessed with a metagenomics approach (454-pyrosequencing). A total of 270 collection points from insect galleries from three locations in Argentina were pooled for pyrosequencing analyses. Two hosts, Populus deltoides and Casuarina cunninghamiana, were independently evaluated to characterize the fungal communities associated to M. mutatus; compare the culture-independent approach with previous culturing studies, in terms of data recovery related to the fungal community composition, and test the specificity of the fungal communities amongst locations and hosts. A Generalized Linear Mixed Model was performed to compare the fungal richness in each dataset, which showed no significant differences between taxa richness amongst locations. Principal Coordinates Analyses showed a separation between fungal communities within the same host, suggesting that host identity would not be crucial to determine the specificity in fungal communities. Candida insectalens and one Fusarium species, present in all hosts and locations, achieved 37.6% of the total relative frequency per taxa. These results complement the data from culturing methods previously reported, thus improving the accuracy and understanding of the fungal assemblages associated to M. mutatus.

We provide scientists and decision-makers with up-to-date information on Megaplatypus mutatus (Coleoptera: Curculionidae: Platypodinae), a forest insect native to South America that has invaded other regions. Emphasis is given to information that may prove relevant for the development of early detection, containment and management programs and improved risk analyses. The increase in global movement of people and goods, coupled with expected climatic scenarios, suggests that M. mutatus may arrive and establish populations in new areas. The major impact of this forest pest has always been reported in exotic tree species, even within its native range. The absence of a coevolutionary history with ‘naïve’ host trees is a relevant factor when analyzing and understanding the magnitude of the problem posed by this beetle and fungi associated with it. Notably, among preferred hosts are the widely planted Eucalyptus and Populus spp., facilitating the invasion of this insect into new regions and posing a threat to commercial forestry.

Currently, the detection of endophytic fungi is determined mostly by invasive methods, including direct isolation of fungal organisms from plant tissue in growth media, molecular detection of endophytic fungi DNA from plant material by PCR, or evaluation under microscopy techniques. In 2 this work we explore the potential of laser biospeckle activity (LBSA) to be used for the detection of endophytic colonization of leaves of a promising energy crop, Jatropha curcas L. We compared the laser biospeckle activity of endophyte infected and uninfected J. curcas leaves. The differences between blade and veins (including midrib) of the studied leaves was validated and growth parameters of the studied plants were also analyzed using the normalized weigthed generalized differences coefficient (nWGD). The obtained results showed a relationship between the endophytic burden of leaves and the LBS, suggesting that LSBA is a useful tools to detect endophytic colonization in situ.Also, the increased water movements inside leaves promoted by endophytic colonization could be explain by the obtained data.