Verticillium wilt (caused by Verticillium dahliae Kleb.) is an important disease affecting olive (Olea europaea L.) production. Effective control of this disease relies on integrated management strategies. In vitro antifungal activity of two hydroxytyrosol (HTyr) enriched extracts (HTE1 and HTE2) obtained from olive mill waste products (OMWP) was assessed against V. dahliae. Inhibitory effects of pure HTyr as a standard, and HTE1 and HTE2 at different concentrations, were evaluated on mycelium growth and conidium germination of V. dahliae. Chemical characterization of HTE1 and HTE2 allowed identification and quantification of HTyr as the main constituent in both extracts along with other low molecular weight phenols. HTE1 showed a higher inhibitory activity in both growth and conidium germination of V. dahliae. At the tested concentrations, low antifungal effects of HTyr were observed. After 3 d, 1 mg mL-1 of HTE1 gave greater inhibition of mycelium growth than HTE2 or HTyr. After 24 h, HTE1 gave 55% inhibition of conidium germination, and HTyr and HTE2 both gave 37% inhibition. This study has demonstrated that phenolic compounds derived from OMWP have antifungal activity against V. dahliae, indicating the potential of these compounds for eco-friendly control of Verticillium wilt.

Olive anthracnose induced by different Colletotrichum species causes dramatic losses of fruit yield and oil quality. The increasing incidence of Colletotrichum fioriniae ( Colletotrichum acutatum species complex) as causal agent of olive anthracnose in Italy, is endorsing new studies on its biology, ecology, and environmental factors such as temperature. Five isolates from different sampling sites in Lazio region (Central Italy) were studied under controlled laboratory conditions aiming to better understand the differences of thermal development among the isolates and to lay the foundations of a future mathematical model able to describe the key aspects of the pathogen's life cycle. The mycelial growth rate and the conidial germination rate were assessed at seven different constant temperatures (5, 10, 15, 20, 25, 30, and 35°C) and fixed relative humidity (100% RH). The obtained dataset was analysed to estimate the parameters of mathematical functions that connect the mycelial growth rate and the spore germination with the environmental temperature. The parameters set provided as the result of this study constitute a key step forward in the biological knowledge of the species and the basis for future formulations of mathematical models that might be the core of decision support systems in an integrated pest management framework.

During the last decade, the European hazelnut (Corylus avellana) has been threatened by several bacterial and fungal infections. In particular, at least four different Pseudomonas species have developed the capability to converge into the same host. However, one of these species, Pseudomonas avellanae, may infect other hosts as well. Here, we newly provide the complete genome sequence of two Pseudomonas avellanae strains obtained by a combination of long Oxford Nanopore Technologies reads (ONT) and short Illumina reads. These have been included in a comparative analysis with all the genomes of Pseudomonas strains known to infect Corylus avellana available on the NCBI database, and the genomes of Pseudomonas avellanae strains infecting other host plants, like Prunus, Actinidia and from the river epilithon. The Pseudomonas strains clustered according to their taxonomy, host and geographic origins. The identification of specific traits related to each population cluster could give us insights regarding the host–pathogen interaction and the host range specificity. Indeed, the Pseudomonas avellanae strains infecting hazelnut have a peculiar set of three type III secretion effectors, while the Pseudomonas avellanae infecting Prunus and Actinidia are carrying the genomic WHOP island, necessary for woody‐host infection. The syringae cluster, instead, contains more phytotoxins, the ice nucleation cluster, but less effectors. Thus, here, we confirmed that the convergence into the same host was possible due to different unrelated mechanisms of infection.

The capability of entomopathogenic fungi to live as plant endophytes is well established. However, their presence in undiscovered environmental niches represents the beginning of a new challenging research journey. Recently, Akanthomyces muscarius (Ascomycota, Cordycipitaceae) (Petch) Spatafora, Kepler & B. Shrestha was isolated from hazelnut buds infested by the big bud mite pest Phytoptus avellanae Nalepa, which makes the buds swollen, reddish, and unable to further develop. Gall formation is known to be regulated by a consortium of microbes and mites, and to better understand the possible role of A. muscarius within the infested gall, its whole genome sequence was obtained using a hybrid approach of Illumina and Nanopore reads. The functional and comparative genomics analysis provided within this study may help answer questions related to the ecology and the entomopathogenicity of this fungus.