Olive (Olea europaea L.) is a very important crop grown in the Mediterranean part of Croatia. Olive branch and fruit dieback symptoms were observed in two olive orchards in Istria, Croatia. The samples from symptomatic trees were collected and brought to the laboratory for analysis. Based on their morphological characterization, isolated fungi were identified as Cytospora sp. Two representative isolates (one per orchard) were taken for molecular analysis, and based on DNA sequence data of the ITS and TUB gene regions, and phylogenetic analysis of the sequences, the isolates were identified as Cytospora pruinosa Défago. To determine pathogenicity, pathogenicity tests were conducted on detached olive branches and two-year-old olive trees in the greenhouse. This is the first report of C. pruinosa causing olive branch and fruit dieback in Croatia.

Phytopathogenic fungi are living organisms that cause plant diseases and great damage to agricultural products. Despite the wide range of commercial fungicide products in use, there is a clear need for new and environmentally friendly fungicides. Here we propose a new ecological fungicide, copper alginate microspheres prepared by ionic gelation. The microspheres were characterized (morphology and topography, encapsulation efficiency, loading capacity, swelling behavior, rheology, kinetics and mechanism of copper ions release) and their in vitro antifungal potential against selected genera of phytopathogenic fungi was evaluated. Copper alginate microspheres inhibited spore germination of Botrytis cinerea. Compared to the control, the inhibition of B. cinerea spore germination (48%) was greater than that of the commercial fungicide Neoram^® (22%). The mycelial growth of Cercospora beticola and Phytophthora ramorum was also significantly inhibited by the addition of copper alginate microspheres. Novel fungicide offer effective disease control while minimizing environmental impact and promoting sustainable agriculture practices.

In May 2021, a tomato producer reported an occurrence of a disease unknown so far in a greenhouse near Split, Croatia. About 30% of plants (cultivar Signora) have been affected. Symptoms resembled ...

Black stem borer, Xylosandrus germanus (Coleoptera: Scolytinae), was first recorded in Croatia in 2009. Until now, the insect has been reported only as a part of ambrosia beetles entomofauna in oak stands (Quercus robur and Quercus petraea). In 2021, severe attack of ambrosia beetles causing tree decline and mortality have been observed in three orchards of hybrid sweet chestnut (Castanea sativa x Castenea crenata). Orchards near Topusko, Marija Bistrica and Vugrovec were inspected for the symptoms. Twenty-seven adult ambrosia beetle specimens were collected from eight samples of damaged sweet chestnut trees, and were identified according to their morphology. All 27 ambrosia beetles were morphologically identified as X. germanus. This is the first record of black stem borer causing damage on cultivated sweet chestnut in Croatia. Considering similar reports from Italy and Slovenia, X. germanus could be regarded as a new, potentially damaging pest in chestnut plantations.