A realized Tuber magnatum niche in the upper Sinni area (south Italy)

A realized Tuber magnatum niche, in the upper Sinni area (Serrapotamo, south Italy), was studied using geographic information system, direct in situ survey and genetic diversity at DNA marker loci. Truffières were north facing, associated with a fine loamy-sandy soil bearing high carbonate content over a conglomerate bead-rock substrate. Target area is located in Pavari's cold and medium-cold Lauretum phithoclimatic belts. Ascoma genomic DNA was analyzed and ITS sequences, microsatellites (MA2, MA4 and MA7), along with M13 minisatellite loci, did show low heteozygosity (HE = 0.153). Serrapotamo genotypes did not express localized markers when compared with Piemonte (north Italy) genetic material. ITS marker, monomorphic within T. magnatum, was efficient at distinguishing T. borchii in a mixture of both. Serrapotamo niche represents a unique T. magnatum diversity spot in the southernmost side of the Mediterranean region. Maintaining Serrapotamo T. magnatum diversity by undertaking conservation measures is adviced

Blended formulations of oregano-sage essential oils: antimicrobial, phytotoxic, and anti-quorum sensing investigations

There is a growing interest in the potential use of essential oils (EOs) as a possible alternative to synthetic pesticides. The formulation of bioinsecticides with different EOs could improve their bioactivities through synergic mechanisms. This study aimed to evaluate the biological activities of three blended oil formulations (BOFs) derived from oregano (Origanum vulgare L.) and sage (Salvia officinalis L.). The chemical composition of the individual EOs was investigated using GC-MS analysis. The BOFs were prepared as follows: i) 25% oregano EO + 25% sage EO (BOF-I); ii) 25% oregano EO + 5% sage EO (BOF-II); iii) 5% oregano EO + 25% sage EO (BOF-III). The BOFs were tested for their phytotoxic effects on Lepidium sativum, Solanum lycopersicum, and Lactuca sativa as well as their antimicrobial activity against some phytopathogens. The tested BOFs were evaluated for their possible anti-quorum sensing activity against Chromobacterium violaceum Schröter. GC-MS analysis revealed that the oregano EO is mainly composed of thymol (76%), p-cymene (5.7%) and carvacrol (3.2%). Whereas the dominant constituents of sage EO were transthujone and camphor. The results demonstrated that all tested BOFs possess an antimicrobial effect higher than each parent EO. In particular, BOF-II showed the highest effect against all tested bacteria and fungi. In addition, the three BOFs showed notable phytotoxic effects against all tested plants, particularly BOF-I. Whereas, the single sage EO at 25% showed the lowest significant phytotoxic effect, indicating its possible use as a natural herbicide. All examined BOFs showed promising quorum quenching activity against C. violaceum, especially at a concentration of 100%

Metagenomic Analysis of Bacterial Community Structure and Dynamics of a Digestate and a More Stabilized Digestate-Derived Compost from Agricultural Waste

Recycling of different products and waste materials plays a crucial role in circular economy, where the anaerobic digestion (AD) constitutes an important pillar since it reuses nutrients in the form of organic fertilizers. Knowledge about the digestate and compost microbial community structure and its variations over time is important. The aim of the current study was to investigate the microbiome of a slurry cow digestate produced on a farm (ADG) and of a more stabilized digestate-derived compost (DdC) in order to ascertain their potential uses as organic amendments in agriculture. The results from this study, based on a partial fragment of 16S bacterial rRNA NGS sequencing, showed that there is a greater microbial diversity in the DdC originated from agricultural waste compared to the ADG. Overall, the existence of a higher microbial diversity in the DdC was confirmed by an elevated number (1115) of OTUs identified, compared with the ADG (494 OTUs identified). In the DdC, 74 bacterial orders and 125 families were identified, whereas 27 bacterial orders and 54 families were identified in the ADG. Shannon diversity and Chao1 richness indexes were higher in DdC samples compared to ADG ones (Shannon: 3.014 and 1.573, Chao1: 68 and 24.75; p< 0.001 in both cases). A possible association between the microbiome composition at different stages of composting process and the role that these microorganisms may have on the quality of the compost-like substrate and its future uses is also discussed

Investigations on Fungi Isolated from Apple Trees with Die-Back Symptoms from Basilicata Region (Southern Italy)

Val d'Agri is an important orchard area located in the Basilicata Region (Southern Italy). A phenomenon affecting cv. "Golden Delicious" apples which lead to tree death has been observed in the past several years in this area. This phenomenon has already been detected in about 20 hectares and is rapidly expanding. The symptoms observed were "scaly bark" and extensive cankers, mainly located in the lower part of the trunk, associated with wood decay. Dead plants ranged from 20% to 80% and, in many cases, trees were removed by farmers. In order to identify the causes of this phenomenon, investigations were started in autumn/winter 2019. In order to determine the possible causal agents, fungal and bacterial isolations, from symptomatic tissues, were performed in laboratory. Bacterial isolations gave negative results, whereas pure fungal cultures (PFCs) were obtained after 3-4 passages on potato dextrose agar (PDA) media. Genetic material was extracted from each PFC and amplified by PCR using three pairs of primers: ITS5/4, Bt2a/Bt2b and ACT-512F/ACT-783R. The amplicons were directly sequenced, and nucleotide sequences were compared with those already present in the NCBI GenBank nucleotide database. All isolated fungi were identified based on morphological features and multilocus molecular analyses. Neofusicoccum parvum, Diaporthe eres and Trametes versicolor were most frequently isolated, while Pestalotiopsis funerea, Phomopsis spp. and Diaporthe foeniculina were less frequently isolated. All nucleotide sequences obtained in this study have been deposited into the EMBL database. Pathogenicity tests showed that N. parvum was the most pathogenic and aggressive fungus, while Phomopsis sp. was demonstrated to be the less virulent one. All the investigated fungi were repeatedly reisolated from artificially inoculated twigs of 2-year-old apple trees, cv. "Golden Delicious", and subsequently morphologically and molecularly identified. The role played by the above-mentioned fungi in the alterations observed in field is also discussed

Garlic (Allium spp.) viruses: detection, distribution and remediation attempts in a European garlic collection

Garlic is an important vegetable crop in numerous countries used as food and natural based medicine. Similar to the majority of vegetatively propagated plants, garlic may be affected by several viruses that can cause severe crop losses. The present study aimed to screen 105 garlic accessions (mother plants) from 5 European countries (Germany, Czech Republic, Poland, Italy, and France) for possible presence of Onion yellow dwarf virus (OYDV), Leek yellow stripe virus (LYSV), Garlic common latent virus (GCLV) and Shallot latent virus (SLV). The occurrence of three Allexiviruses (GarV-A, GarV-B and GarV-C) in mixed assays was also investigated. Meristem-tip culture assays were performed in order to attempt eradication of the studied viruses. Garlic viruses identification was made by ELISA and RT-PCR. ELISA outcomes showed that all 105 garlic accessions were infected by different virus combinations. The OYDV and LYSV were identified, by ELISA, in all countries at 96% and 88,6% respectively and by RT-PCR at 99% and 96%. Furthermore, GCLV and SLV were detected by ELISA in about 88% and by RT-PCR at 89% and 90%, respectively with the exception of the studied Allexiviruses which were not amplified by RT-PCR with ALLEX1/ALLEX2 primers. Smaller meristem size (0,3-1,5 mm) led to better virus elimination efficiency (29%) compared to 8% obtained for the larger size (2-2,5 mm). The outcomes were opposite (16% vs. 90%) for plants regeneration. Virus elimination efficiency was linked to the virus type, e.g., OYDV and LYSV were eradicated at 90% while GCLV and Allexiviruses were difficult to eliminate (57,4% and 55,6% of eradication). Given the economic relevance of garlic crops worldwide and the frequently reported incidence of viral infections, it is important to make virus-free germplasm available. Therefore, investigating the garlic germplasm sanitary status and constantly improving it is of crucial importance aiming to increase the overall garlic production

Alternative Control of Phragmidium rubi-idaei Infecting Two Rubus Species

Organic berry plantations have been gaining popularity among farmers during recent years. Even so, farmers experience serious challenges in disease control management, which is a concern in organic farming. Phragmidiumrubi-idaei (DC) P. Karst is the pathogen responsible for blackberry and raspberry rust disease, one of the most present and active diseases in plantations. The antifungal certified products found on the organic farming market offer the opportunity for an efficient control strategy over plant pathogens in fruit shrub plantations. In this study, 5 natural based products—namely Altosan, Mimox, Canelys, Zitron, and Zeolite—were tested for their fungistatic effect over P. rubi-idaei. The experiments were carried out under laboratory conditions, performing observations over the impact of organic products, used at different concentration levels, on rust conidia germination. Moreover, field experiments were conducted in order to evaluate the efficiency of different treatments for rust control on raspberry (‘Polka’, ‘Veten’ and ‘Heritage’) and blackberry (‘Thorn Free’, ‘Chester’ and ‘Loch Ness’) varieties. Data analysis based on ANOVA tests showed significant differences between the tested variants and the control sample at p < 0.001. Furthermore, LSD test confirmed differences between all substances tested (p < 0.005). The natural products Canelys (formulated with cinnamon) and Zytron (based on citrus extract) have proven the highest inhibitory capacity for conidia germination during in vitro tests registering values of 80.42% and 78.34%, respectively. The same high inhibitory rates against rust pathogen were kept also in the field tests using the same two natural-based products mentioned earlier. In addition, outcomes from this study demonstrated that Zeolite is not recommended for raspberry or blackberry rust control

Antimicrobial and antioxidant properties and quantitative screening of phytochemicals of Fraxinus excelsior L. and Eschscholtzia californica Cham. mother tinctures

The antioxidant and antimicrobial activities of Fraxinus excelsior L. and Eschscholtzia californica Cham. mother tinctures against a range of foodborne bacteria were investigated to determine the major components and to analyse the action spectrum and antimicrobial effectiveness of the extracts. Results demonstrated a significant antioxidant activity of Fraxinus excelsior L. and a lower activity of Eschscholtzia californica Cham. and a good chemical phenolic composition with the highest content of flavonoids. The Fraxinus excelsior L. and Eschscholtzia californica Cham. mother tinctures demonstrated a middle-high antimicrobial activity against, respectively, 66.67% and 43.33% of all tested bacteria. The inhibitory activity showed a moderate effect on the growth of the sensitive strains in presence of extracts minimum inhibitory concentration. The synergistic actions of bioactive compounds detected in the extracts might be on the basis of antioxidant and biological activities observed and should be used in pharmaceutical, food preservation, alternative medicine and natural therapies fields

The bio-patina on a hypogeum wall of the Matera-Sassi rupestrian church "San Pietro Barisano" before and after treatment with glycoalkaloids

The investigation focused on the deterioration of the walls in the hypogeum of "San Pietro Barisano" rupestrian church, located in the Matera-Sassi (Southern Italy), one of the UNESCO World Heritage sites. The study evaluated the biocide activity of a mixture of natural glycoalkaloids (G.A.s) extracted from the unripe fruit of Solanum nigrum and applied to clean a hypogeum wall surface in the church affected by green patinas. The analyzed patina, collected before treatment and, at pre-established times, after treatment, showed changes in chemical composition detected by XPS, accompanied by visible discoloration and biological activity variation. The biocidal action of the glycoalkaloids mixture, directly employed on the wall surface, was effective after about four weeks for most patina colonizers but not for the fungal species that can migrate and survive in the porosities of the calcarenite. Consequently, the cleaning procedure requires the integration of fungicidal actions, combined with the consolidation of the surfaces, to obtain complete bioremediation and avoid subsequent biological recolonization. SEM images and associated microanalysis of pretreated green patina have revealed the biocalcogenity of some autochthonous microorganisms, thus preluding to their eventual isolation and reintroduction on the wall surface to act as consolidants once the bio-cleaning phase has been completed

Comparison of Bioactive Substances Content between Commercial and Wild-Type Isolates of Pleurotus eryngii

Mushrooms belonging to Pleurotus genus have been demonstrated to have important nutritional and medicinal value and their regular intake prevent many diseases, reduce the infection probability and increase immunity. In order to investigate the bioactive compounds produced by seven commercial (‘142 F’, ‘142 E’, ‘D+’, ‘V turbo’, ‘V 142’, ‘A 12’, ‘V 160’) and five wild-type (‘Albino 1107’, ‘Altamura 1603’, ‘Muro Lucano 139’, ‘Conversano 1250’, ‘Albino beige chiaro 1094’) P. eryngii isolates, the following qualitative analyses were performed: Total polyphenol content, antioxidant activity (EC50 of ABTS) and antiradical power (ARP) in fresh lyophilized and dry basidioma, and water content, -glucans and phenolic compounds in fresh samples. Standard methods were employed for each of the above mentioned aims. Total polyphenol content was diverse among the P. eryngii isolates. In particular, an elevated polyphenolic content was found in fresh lyophilized P. eryngii samples of the commercial isolates ‘V 142’ followed by ‘A 12’. The highest antiradical activity (ARP) was obtained by ‘Muro Lucano 139’ isolate. Wild P. eryngii isolates were characterized by higher water and -glucans contents compared to the commercial ones, and the highest values were registered for the ‘Albino beige chiaro 1094’ isolate. In conclusion, the present study allowed us to identify the commercial and wild-type P. eryngii isolates from the Basilicata region, with high nutritional and medicinal value based on their bioactive compounds

preliminary studies on productivity of white pleurotus eryngii isolates in protected cultivation

Four isolates of Pleurotus eryngii species-complex, originating from different basidiomata growing in a mountainous area of the Basilicata region (southern Italy) and characterized by white pileus cuticle (Wh A, Wh B, Wh C, and Wh D) were compared, in artificial cultivation conditions, to other isolates of the same mushroom with beige (Be 3, Be 5) or brown cap (Br 1, Br 2) originating from the same area of the former or selected among the commercial ones (Com 142 and Com 164) in order to evaluate their productivity and morphological features. The experiments were carried out in a greenhouse belonging to the Faculty of Agriculture, University of Bari Aldo Moro, in autumn winter 2010-2011, using substrate bags well colonized by P. eryngii mycelium and kept at 4-6°C for 5 months. Wh A and Wh D and, less significantly, Wh C, Be 5 and Com 142, produced a fresh basidioma yield significantly higher than the five other tested isolates (Wh B, Be 3, Br 1, Br 2 and Com 164). Only Com 142 produced the basidiomata of medium and maximum size significantly heavier and with larger pileus diameter than other tested isolates. Com 142 also resulted significantly different, for the basidiomata number/substrate bag, from the white pileus cuticle isolates except for Wh B. All tested isolates concentrated almost all (90-95%) of the sporophore yield in the first basidioma flush. No significant differences were found among all tested P. eryngii isolates in terms of yield earliness