Shot hole disease on Prunus laurocerasus caused by Neofusicoccum parvum in Serbia

Between 2010-2014 symptoms of a shot hole disease were observed on cherry laurel (Prunus laurocerasus L.) trees and shrubs in parks and other public plantings in Belgrade, Serbia. Ten symptomatic leaves were collected from each of the diseased plants and the associated fungus isolated and identified using multi-gene phylogenetic analyses and asexual morphological characters. The pathogen was identified as Neofusicoccum parvum. The same symptoms were produced when the pathogen was inoculated on test plants. To the best of our knowledge, this is the first report of N. parvum causing shot hole disease on P. laurocerasus.Tree Protection Co-operative Programme (TPCP), the University of Pretoria (South Africa), the Ministry of Education and Science of the Republic of Serbia (TR37008), European Cooperation in Science and Technology (COST) Actions Pathway Evaluation in Pest Risk Management In Transport (PERMIT FP1002) and A global network of nurseries as early warning system against alien tree pests (Global Warning FP1401).http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1439-03292017-12-31hb2017Microbiology and Plant Patholog

The use of salicylaldehyde derivatives as a nitrogen source for antibiotic production by Streptomyces hygroscopicus CH-7

In the present work, four derivatives of salicylaldehyde (salicylaldehyde-hydrazone, phenylhydrazone, semicarbazone and thiosemicarbazone) were synthesized using both conventional (95% ethanol) and green (crude glycerol from biodiesel production) solvents. The obtained compounds were identified by elemental microanalysis, as well as FTIR, UV/Vis and H-1-NMR spectroscopic methods. Yields of 93-98% of the compounds in crude glycerol were achieved within 10-25 min. The derivatives of salicylaldehyde and crude glycerol were used as a nitrogen and carbon source, respectively, in the medium for antibiotic (hexaene H-85 and azalomycine B) production by Streptomyces hygroscopicus CH-7. The highest concentrations of hexaene H-85 and azalomycine B were achieved in the medium containing salicylaldehyde-thiosemicarbazone (198 and 69 mu g/cm(3), respectively). Derivatives of salicylaldehyde also impacted the strain morphology. In the media with salicylaldehyde- phenylhydrazone and salicylaldehyde-thiosemicarbazone, S. hygroscopicus CH-7 grew like large dispersive pellets with long twisted filaments that produced the highest yield of the antibiotics

Worldwide diversity of endophytic fungi and insects associated with dormant tree twigs

International trade in plants and climate change are two of the main factors causing damaging tree pests (i.e. fungi and insects) to spread into new areas. To mitigate these risks, a large-scale assessment of tree-associated fungi and insects is needed. We present records of endophytic fungi and insects in twigs of 17 angiosperm and gymnosperm genera, from 51 locations in 32 countries worldwide. Endophytic fungi were characterized by high-throughput sequencing of 352 samples from 145 tree species in 28 countries. Insects were reared from 227 samples of 109 tree species in 18 countries and sorted into taxonomic orders and feeding guilds. Herbivorous insects were grouped into morphospecies and were identified using molecular and morphological approaches. This dataset reveals the diversity of tree-associated taxa, as it contains 12,721 fungal Amplicon Sequence Variants and 208 herbivorous insect morphospecies, sampled across broad geographic and climatic gradients and for many tree species. This dataset will facilitate applied and fundamental studies on the distribution of fungal endophytes and insects in trees

Trichoderma spp. From pine bark and pine bark extracts: Potent biocontrol agents against botryosphaeriaceae

Pinus sylvestris bark represents a rich source of active compounds with antifungal, antibacterial, and antioxidant properties. The current study aimed to evaluate the antifungal potential of P. sylvestris bark against Botryosphaeria dothidea, Dothiorella sarmentorum, and Neofusicoccum parvum (Botryosphaeriaceae) through its chemical (water extracts) and biological (Trichoderma spp. isolated from the bark) components. The water bark extracts were prepared at two temperatures (80 and 120◦C) and pH regimes (7 and 9). The presence of bark extracts (30%) caused inhibition of mycelial growth of B. dothidea and D. sarmentorum for 39 to 44% and 53 to 60%, respectively. Moreover, we studied the antagonistic effect of three Trichoderma isolates originating from the pine bark. Trichoderma spp. reduced growth of B. dothidea by 67%–85%, D. sarmentorum by 63%–75% and N. parvum by 55%–62%. Microscopic examination confirmed typical mycoparasitism manifestations (coiling, parallel growth, hook-like structures). The isolates produced cellulase, β-glucosidase and N-acetyl-β-glucosaminidase. The volatile blend detected the emission of several volatile compounds with antimicrobial activity, including nonanoic acid, cubenene, cis-α-bergamotene, hexanedioic acid, and verticillol. The present study confirmed in vitro potential of P. sylvestris bark extracts and Trichoderma spp. against the Botryosphaeriaceae. The study is an important step towards the use of environmentally friendly methods of Botryosphaeriaceae disease control

Climate, host and geography shape insect and fungal communities of trees

Non-native pests, climate change, and their interactions are likely to alter relationships between trees and tree-associated organisms with consequences for forest health. To understand and predict such changes, factors structuring tree-associated communities need to be determined. Here, we analysed the data consisting of records of insects and fungi collected from dormant twigs from 155 tree species at 51 botanical gardens or arboreta in 32 countries. Generalized dissimilarity models revealed similar relative importance of studied climatic, host-related and geographic factors on differences in tree-associated communities. Mean annual temperature, phylogenetic distance between hosts and geographic distance between locations were the major drivers of dissimilarities. The increasing importance of high temperatures on differences in studied communities indicate that climate change could affect tree-associated organisms directly and indirectly through host range shifts. Insect and fungal communities were more similar between closely related vs. distant hosts suggesting that host range shifts may facilitate the emergence of new pests. Moreover, dissimilarities among tree-associated communities increased with geographic distance indicating that human-mediated transport may serve as a pathway of the introductions of new pests. The results of this study highlight the need to limit the establishment of tree pests and increase the resilience of forest ecosystems to changes in climate

Biotic threats for 23 major non-native tree species in Europe

For non-native tree species with an origin outside of Europe a detailed compilation of enemy species including the severity of their attack is lacking up to now. We collected information on native and non-native species attacking non-native trees, i.e. type, extent and time of first observation of damage for 23 important non-native trees in 27 European countries. Our database includes about 2300 synthesised attack records (synthesised per biotic threat, tree and country) from over 800 species. Insects (49%) and fungi (45%) are the main observed biotic threats, but also arachnids, bacteria including phytoplasmas, mammals, nematodes, plants and viruses have been recorded. This information will be valuable to identify patterns and drivers of attacks, and trees with a lower current health risk to be considered for planting. In addition, our database will provide a baseline to which future impacts on non-native tree species could be compared with and thus will allow to analyse temporal trends of impacts

Worldwide diversity of endophytic fungi and insects associated with dormant tree twigs

International trade in plants and climate change are two of the main factors causing damaging tree pests (i.e. fungi and insects) to spread into new areas. To mitigate these risks, a large-scale assessment of tree-associated fungi and insects is needed. We present records of endophytic fungi and insects in twigs of 17 angiosperm and gymnosperm genera, from 51 locations in 32 countries worldwide. Endophytic fungi were characterized by high-throughput sequencing of 352 samples from 145 tree species in 28 countries. Insects were reared from 227 samples of 109 tree species in 18 countries and sorted into taxonomic orders and feeding guilds. Herbivorous insects were grouped into morphospecies and were identified using molecular and morphological approaches. This dataset reveals the diversity of tree-associated taxa, as it contains 12,721 fungal Amplicon Sequence Variants and 208 herbivorous insect morphospecies, sampled across broad geographic and climatic gradients and for many tree species. This dataset will facilitate applied and fundamental studies on the distribution of fungal endophytes and insects in trees.Datapaper</p