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The invasive apricot aphid ( Myzus mumecola Matsumura) is an important pest of apricot trees ( Prunus armeniaca L.). In the presented study, laboratory bioassays using treated leaf disks of apricot were conducted to test the efficacy of twelve insecticides according to the maximum field dose. Additionally, dose-response curves were established for selected insecticides, and the effects on colony development were evaluated. Furthermore, a field trial was conducted to investigate the effectiveness of commonly used insecticides in apricot cultivation. The dose-response curves showed LC 50 values ranging from 0.08 mg/L for flupyradifurone, 0.15 mg/L for acetamiprid, 0.70 mg/L for etofenprox, 1.89 mg/L for sulfoxaflor, 2.64 mg/L for pirimicarb, 3.97 mg/L for deltamethrin, up to 6.79 mg/L for tau-fluvalinate. These aforementioned insecticides resulted in mortality rates ranging from 95 to 100% at the field dose. Azadirachtin, flonicamid, and pyrethrins showed mortality rates of 27 to 45%. Spirotetramat reduced the colony development and decreased the number of infested shoots by 86%. Spinosad, which is not recommended against aphids, showed minimal impact; reducing the number of exuviae in nymphs in the colony development bioassay. It can be concluded that the majority of the tested insecticides are effective against M. mumecola .

Alternaria sp. infections on apple ( Malus × domestica Borkh.) lead to impaired fruit quality and yield losses by leaf blotches and fruit spots, caused by host-specific toxins (HSTs) of the Alternaria apple pathotype like AM-toxins. Fungal isolates were obtained during severe outbreaks on cv. Gala, Golden Delicious, and Cripps Pink (cov) /Rosy Glow (cov) in South Tyrol and other regions in northern Italy. The isolates were tested for pathogenicity using in vitro assays with detached apple leaves. Conidial suspensions of pathogenic isolates were shown to provoke necrotic lesions also in apple seedlings and on fruits. Detached-leaf assay-guided fractionation of the isolates' culture supernatant and a high-resolution liquid chromatography-mass spectrometry (LC-MS) analysis tentatively identified 27 known Alternaria phytotoxins and a new putative toxin, (3ξ,4ξ,5ξ,6ξ,7ξ,11ξ)-3,6-dihydroxy-8-oxo-9-eremophilene-12-oic acid ( 1 ). The constitution and the relative configuration of the ring stereocenters of 1 were elucidated by NMR spectroscopy, revealing unique structural features among Alternaria phytotoxins. Indeed, molecular analysis revealed the lack of the toxin-related genes AMT1 , AMT4 , and AMT14 in all isolates from the region, suggesting that Alternaria apple blotch in the area was associated with another metabolite ( 1) .

During a study of yeast diversity in Azorean vineyards, four strains were isolated which were found to represent a novel yeast species based on the sequences of the internal transcribed spacer (ITS) region (ITS1-5.8S-ITS2) and of the D1/D2 domain of the large subunit (LSU) rRNA gene, together with their physiological characteristics. An additional strain isolated from Drosophila suzukii in Italy had identical D1/D2 sequences and very similar ITS regions (five nucleotide substitutions) to the Azorean strains. Phylogenetic analysis using sequences of the ITS region and D1/D2 domain showed that the five strains are closely related to Clavispora lusitaniae , although with 56 nucleotide differences in the D2 domain. Intraspecies variation revealed between two and five nucleotide differences, considering the five strains of Clavispora santaluciae . Some phenotypic discrepancies support the separation of the new species from their closely related ones, such as the inability to grow at temperatures above 35 °C, to produce acetic acid and the capacity to assimilate starch. Neither conjugations nor ascospore formation were observed in any of the strains. The name Clavispora santaluciae f.a., sp. nov., is proposed to accommodate the above noted five strains (holotype, CBS 16465 T ; MycoBank no., MB 835794).

Sustainable strategies such as classical or augmentative biological control are currently being evaluated for the long-term management of the alien invasive pest Halyomorpha halys (Stål) (Hemiptera: Pentatomidae). A three-year study carried out in northeastern Italy was performed to investigate the distribution and field performance of the H. halys egg parasitoid Trissolcus mitsukurii (Ashmead) (Hymenoptera: Scelionidae), in comparison with other parasitoid species. In the study area, adventive populations of T. mitsukurii were present since 2016, representing the earliest detection of this species in Europe. Trissolcus mitsukurii was the most abundant parasitoid and showed a higher "parasitoid impact" (i.e., number of parasitized eggs over the total number of field-collected eggs) compared to the other species, i.e., Anastatus bifasciatus (Geoffroy) (Hymenoptera: Eupelmidae), Trissolcus basalis (Wollaston) and Trissolcus kozlovi Rjachovskij (Hymenoptera: Scelionidae). The hyperparasitoid Acroclisoides sinicus (Huang and Liao) (Hymenoptera: Pteromalidae) was also recorded. Phylogenetic analysis of T. mitsukurii population distinguished two clades, one covering samples from Italy, Japan and China, the other from South Korea. The present study provides promising results for the biological control of a pest that is having a dramatic impact on a wide range of crops worldwide.

Acetylation of histones is a key regulatory mechanism of gene expression in eukaryotes. GcnE is an acetyltransferase of Aspergillus nidulans involved in the acetylation of histone H3 at lysine 9 and lysine 14. Previous works have demonstrated that deletion of gcnE results in defects in primary and secondary metabolism. Here we unveil the role of GcnE in development and show that a ∆gcnE mutant strain has minor growth defects but is impaired in normal conidiophore development. No signs of conidiation were found after 3 days of incubation, and immature and aberrant conidiophores were found after 1 week of incubation. Centroid linkage clustering and principal component (PC) analysis of transcriptomic data suggest that GcnE occupies a central position in Aspergillus developmental regulation and that it is essential for inducing conidiation genes. GcnE function was found to be required for the acetylation of histone H3K9/K14 at the promoter of the master regulator of conidiation, brlA, as well as at the promoters of the upstream developmental regulators of conidiation flbA, flbB, flbC, and flbD (fluffy genes). However, analysis of the gene expression of brlA and the fluffy genes revealed that the lack of conidiation originated in a complete absence of brlA expression in the ∆gcnE strain. Ectopic induction of brlA from a heterologous alcA promoter did not remediate the conidiation defects in the ∆gcnE strain, suggesting that additional GcnE-mediated mechanisms must operate. Therefore, we conclude that GcnE is the only nonessential histone modifier with a strong role in fungal development found so far., (Copyright © 2014 by the Genetics Society of America.)

Gene replacement via homologous double crossover in filamentous fungi requires relatively long (preferentially >0.5 kb) flanking regions of the target gene. For this reason, gene replacement cassettes are usually constructed through multiple cloning steps. To facilitate gene function studies in filamentous fungi avoiding tedious cloning steps, we have developed a PCR-assisted DNA assembly procedure and applied it to delete genes in filamentous fungi. While the principle of this procedure is essentially the same as other recently reported PCR-based tools, our technique has been effectively used to delete 31 genes in three fungal species. Moreover, this PCR-based method was used to fuse more than 10 genes to a controllable promoter. In this report, a detailed protocol for this easy to follow procedure and examples of genes deleted or over-expressed are presented. In conjunction with the availability of genome sequences, the application of this technique should facilitate functional characterization of genes in filamentous fungi. To stream line the analysis of the transformants a relatively simple procedure for genomic DNA or total RNA isolation achieving approximately 100 samples/person/day is also presented.

Stationary-phase cells displayed a distribution of relaxed plasmids and had the ability to recover plasmid supercoiling as soon as nutrients became available. Preexisting gyrase molecules in these cells were responsible for this recovery. Stationary-phase rpoS cells showed a bimodal distribution of plasmids and failed to supercoil plasmids after the addition of nutrients, suggesting that rpoS plays a role in the regulation of plasmid topology during the stationary phase.