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Phomopsis cane and leaf spot (PCLS) is an important disease of grapevines, which is mainly caused by Diaporthe ampelina. Dispersal dynamics of D. ampelina spores were investigated in two vineyards, one in North Italy and one in Montenegro, by using spore samplers that collected alpha and beta conidia from rain water running off from PCLS-affected canes. The canes were collected from each vineyard, deployed and overwintered in the corresponding vineyards. In each of three years (2016, 2017, and 2018), conidial dispersal was investigated during one (Montenegro) or two (Italy) growing seasons following the deployment of the PCLS-affected canes. In the first growing season following cane deployment in both vineyards, alpha conidia were mostly found in runoff water after grapevine bud break, especially in April and May, and beta conidia were regularly found in numbers comparable to alpha conidia, most frequently from June to September. In Italy, high numbers of alpha and beta conidia were also collected during the second growing season following cane deployment. The dispersal dynamics of alpha conidia over time were described by a Gompertz equation using hydrothermal time (i.e., the accumulated effect of temperature on the maturation rate of pycnidia on days in which the number of hours of wetness was ≥ 6 or 9 h), with R2 and concordance correlation coefficient >0.9. Rain (≥ 0.2 mm) was a good predictor of conidial dispersal, with an overall accuracy of 0.97. These results increase our understanding of D. ampelina spore dispersal and should be integrated into warning systems for PCLS management.

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In the continuation of our systematic research of pyrazole coordination compounds, complexes of Cu(II), Ni(II), Co(II) and Zn(II) with 4-nitro-3-pyrazolecarboxylic acid ligand (L) were synthesized in the reaction of warm ethanolic solutions of the ligand and CuCl 2 Á2H 2 O, Ni(CH 3 COO) 2 , CoCl 2 Á6H 2 O and Zn(CH 3 COO) 2 , mixed in the metal-to-ligand ratio of 1:2. As the compounds could not be obtained in the form suitable for single-crystal structure analysis, their bis(ligand) structures, ML 2 (M = Cu II , Ni II , Co II and Zn II ) were proposed on the basis of elemental analysis, IR spectrometry, conductometric and TG-MS measurements. The low conductivity of the compounds additionally supports the deprotonation of the ligand and the formation of neutral complexes. The solvent content was calculated using the thermogravimetric (TG) data. According to TG data, the copper(II) compound crystallizes with 8 while nickel(II) complex with 4 water molecules, CuL 2 Á8H 2 O, NiL 2 Á4H 2 O. Complexes of Co(II) and Zn(II) contain 1 and 1.5 water molecules. Despite the differences in solvation properties, the high similarity in the course of the decomposition refers to the similar coordination mode of the organic ligand. The crystal and molecular structures of HLÁH 2 O and NH 4 [LHL] were determined by single-crystal X-ray structure analysis. Biological research based on determining the inhibition effect of commercial fungicide Cabrio top, ligand, and all newly synthesized complexes on Ph. viticola has been carried out using the phytosanitary method.

Aquatain® mosquito formulation (AMF) is a silicone‐based monomolecular film, which has recently been approved for use in the European Union. The physical mode of action based on lowering water surface tension prevents mosquito larvae/pupae respiration. Additionally, AMF disables gravid females from landing on the water surface and obstructs the natural oviposition process. Due to multistage effects on mosquitoes, AMF could be a product of choice for defined water body and container breeders such as Culex pipiens L. complex, principal vector of West Nile virus in Europe, and the invasive Aedes albopictus (Skuse) (both Diptera: Culicidae), vector of dengue and chikungunya viruses. The primary objectives of this study were to evaluate the efficacy of AMF, to determine the susceptibility of the immature forms of C. pipiens and A. albopictus, and the persistence/longevity of the product to suppress the eclosion of adults. AMF achieved high mortality rates of juvenile A. albopictus and C. pipiens under laboratory conditions. However, in the field C. pipiens larvae showed higher susceptibility to AMF than A. albopictus. Pupae of the two mosquito species were highly susceptible to the presence of AMF. When C. pipiens juveniles were exposed to AMF in the wild, effects lasted for 21 days in densely covered water bodies and 56 days in water recipients with less vegetation. In both breeding sites, natural habitat and artificial water recipient, the two mosquito species with high impact on public health in Europe could successfully be suppressed by application of AMF (1 ml m−2).

Phomopsis cane and leaf spot (PCLS), known in Europe as “excoriose,” is an important fungal disease of grapevines caused by Diaporthe spp., and most often by Diaporthe ampelina (synonym Phomopsis viticola). PCLS is re-emerging worldwide, likely due to climate change, changes in the management of downy mildew from calendar- to risk-based criteria that eliminate early-season (unnecessary) sprays, and the progressive reduction in the application of broad-spectrum fungicides. In this study, a mechanistic model for D. ampelina infection was developed based on published information. The model accounts for the following processes: (i) overwintering and maturation of pycnidia on affected canes; (ii) dispersal of alpha conidia to shoots and leaves; (iii) infection; and (iv) onset of disease symptoms. The model uses weather and host phenology to predict infection periods and disease progress during the season. Model output was validated against 11 independent PCLS epidemics that occurred in Italy (4 vineyards in 2019 and 2020) and Montenegro (3 vineyards in 2020). The model accurately predicted PCLS disease progress, with a concordance correlation coefficient (CCC) = 0.925 between observed and predicted data. A ROC analysis (AUROC>0.7) confirmed the ability of the model to predict the infection periods leading to an increase in PCLS severity in the field, indicating that growers could use the model to perform risk-based fungicide applications.

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Species of Zygophiala are components of the sooty blotch and flyspeck complex that blemish the cuticle of fruits reducing their economic value. In our study, six strains were isolated from apple fruit collected in orchards in Montenegro. Zygophiala montenegroensis is a newly described species based on its unique morphological characteristics and the analysis of multiple sequences including the internal transcribed spacer of the rDNA, the partial translation elongation factor 1-alpha and the actin genes. Zygophiala cylindrica is described as a new record in Montenegro and Europe.