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Protoplast fusion technology originated from cell-cell fusion technology in the 1950s and was initially applied to animal cells. The advantage of applying it in the field of edible fungi breeding is that compared with conventional natural selection and hybrid breeding methods, it could more effectively overcome certain incompatibility obstacles to achieve distant hybridization, and more purposefully select parents to obtain new varieties with outstanding characteristics. For these reasons protoplast fusion technology is becoming of great significance for the improvement of edible fungi strains, the breeding of new varieties, and the taming of difficult-to-cultivate species. At present, relatively stable and capable-of-fruiting fusants are limited to several genus and species, and using protoplast fusion for distant hybridization requires new breakthroughs overcoming vegetative incompatibilities. Technically, the acquisition and identification of fusants could also be improved to a more controllable approach. This article focuses on the longitudinal discussion of the role of protoplast fusion technology in the genetic breeding of edible fungi. It explains: i) the preparation and regeneration of protoplasts in the process, ii) the specific methods of fusion, iii) the identification, mutagenesis, and rejuvenation of fusants, and iv) possible impacts of two incompatible systems. Certain application practice cases are also introduced to summarize its promotion prospects.

Abstract Background Plastic is one of the most widely used materials worldwide in various fields, including packaging and agriculture. Its large quantities require proper disposal and for this reason more and more attention is paid to the issue of degrading plastic. Thanks to the production of non-specific enzymes, fungi are able to attack complex and recalcitrant xenobiotics such as plastics. In recent years, several spectroscopic methods were used to study the plastic degradation ability of different fungal species. Among these, Fourier transform infrared (FT-IR) and FT-Raman spectroscopy techniques are the most used. Surface-enhanced Raman scattering (SERS) spectroscopy is a powerful technique which uses metal nanoparticles (NPs) to enhance the Raman signal of molecules adsorbed on the NPs surface. In this work, the isolation of different fungi from field-collected plastic debris and the ability of these isolates to growth and colonizing the low-density polyethylene (LDPE) were explored by using scanning electron microscope (SEM), attenuated total reflectance-Fourier transform infrared (ATR-FTIR) and SERS spectroscopies. Results Forty-seven fungal isolates belonging to 10 genera were obtained; among them only 11 were able to grow and colonize the LDPE film. However, after 90 days trial, only one isolate of Cladosporium cladosporioides (Clc/1) was able to carry out the initial degradation of the LDPE film. In particular, based on SEM observations, small cavities and depressed areas of circular shape were visible in the treated samples. Additionally, ATR-FTIR, normal Raman and SERS analyses supported the structural changes observed via SEM. Notably, ATR-FTIR and normal Raman spectra showed a significant decrease in the relative intensity of the methylene group bands. Similarly, the SERS spectra of LDPE after the fungal attack, confirmed the decrease of methylene groups bands and the appearance of other bands referring to LDPE polyphenolic admixtures. Conclusions These results suggest that Cladosporium cladosporioides Clc/1 is able to carry out an initial degradation of LDPE. Moreover, combining ATR-FTIR, Raman and SERS spectroscopies with SEM observations, the early stages of LDPE degradation can be explored without any sample pretreatment. Graphical Abstract

A recurrent task in coordinated systems is managing (estimating, predicting, or controlling) signals that vary in space, such as distributed sensed data or computation outcomes. Especially in large-scale settings, the problem can be addressed through decentralised and situated computing systems: nodes can locally sense, process, and act upon signals, and coordinate with neighbours to implement collective strategies. Accordingly, in this work we devise distributed coordination strategies for the estimation of a spatial phenomenon through collaborative adaptive sampling. Our design is based on the idea of dynamically partitioning space into regions that compete and grow/shrink to provide accurate aggregate sampling. Such regions hence define a sort of virtualised space that is "fluid", since its structure adapts in response to pressure forces exerted by the underlying phenomenon. We provide an adaptive sampling algorithm in the field-based coordination framework, and prove it is self-stabilising and locally optimal. Finally, we verify by simulation that the proposed algorithm effectively carries out a spatially adaptive sampling while maintaining a tuneable trade-off between accuracy and efficiency.

The ascomycetes in the genus Morchella (commonly called morels) have a considerable economic and biotechnological value for their culinary and medicinal proprieties. However, their biotechnological interest is not limited to the fruiting body cultivation, but also in mycelial production to obtain bioactive compounds and other biotech products. In order to better exploit the biotechnological potentialities of morels it is necessary to improve the knowledge on their biology and mycelial characteristics. In this paper morphological and growth characteristics of mycelia, as well as biomass formation of Italian collections of five edible medicinal Morchella species [M. esculenta (L.) Pers., M. dunalii Boud., M. importuna M. Kuo, O'Donnell & T.J. Volk, M. disparilis Loizides & P.-A. Moreau and M. purpurascens (Krombh. ex Boud.) Jacquet.] are presented.

Pedodiversity is generally neglected in studies concerning soil organic carbon (SOC). Therefore, this investigation aimed to explore the effect of soil types on the following: (1) soil processes related to organic matter (OM) dynamics along the profile; and (2) the microbial community and functionality within the uppermost horizon. Humic Dystrudepts (HD), Typic Dystrudepts (TD), and Humic Lithic Dystrudepts (HLD) were selected in beech forests of the Apennine ridge in the Emilia-Romagna Region (Italy). Soils were sampled by horizons until parent material, and physico-chemical and functional analyses were performed. The results showed that both HD and HLD soils had a higher SOC accumulation than TD, particularly within the deeper horizons. Such accumulation might be due to the lower turnover rate of soil OM forms, namely fulvic acid-like substances, humic acid-like substances, and non-extractable OM. Noteworthy, the A horizons showed slight differences in SOC among the soil types, suggesting similar SOC decomposition processes. This fact was confirmed by the lack of differences in microbial DNA-based diversity and functionality. This study highlighted the importance of combining pedodiversity and microbial diversity for a wider perspective on SOC dynamics.

Tuber magnatum Picco is the most expensive of the truffles and a great deal of research has been carried out in an attempt to solve the mysteries of its ecology and biology. However, considerable work remains to be done particularly on those secrets of its life cycle that remain a mystery. It is known that T. magnatum is heterothallic, but it has yet to be determined how fertilization occurs between the two strains of different mating types. It is also known that the white truffle is an ectomycorrhizal fungus, and its mycorrhizas can be produced in greenhouses, but then they seem to disappear in the field. The role of other soil microorganisms, fungi and bacteria, on its soil mycelial development and fructification is intriguing but is far from being completely understood. All these uncertainties have made the cultivation of T. magnatum extremely difficult and only recently have we had the scientific proofs that it is possible. Even so, many questions remain unanswered and the management practices of T. magnatum plantations are still to be better defined to also enable the taming of this truffle.

Abstract Background Mushrooms have always been considered an important source of food and biologically active compounds with several medicinal properties. In recent years, different methods were used to study the quality and chemical composition of mushrooms. Among these, Fourier transform infrared (FT-IR) and FT-Raman spectroscopy techniques have been successfully applied to identify different mushroom species. However, the structural biomolecule components existing in the mycelium or in the fruiting bodies may produce strong fluorescence emission that overlaps the Raman radiation, thus avoiding their analyses by Raman. SERS spectroscopy is a powerful technique which uses metal nanoparticles (NPs) to enhance the Raman signal of molecules adsorbed on the NPs surface. In addition, SERS is able to quench the macromolecule florescence. In this work, we have employed silver nanoparticles in order to get mushroom fingerprints based on SERS as quick procedure to analyze and identify different chemical compounds from the fruiting bodies of six edible and/or medicinal mushrooms: Lentinula edodes, Ganoderma lucidum, Pleurotus cornucopiae, Pleurotus ostreatus, Tuber aestivum and Tuber magnatum. Results SERS analyses performed directly on fruiting body fragments produced characteristic spectra for each species. One group of mushrooms (L. edodes, G. lucidum, T. aestivum and T. magnatum) was dominated by the bands of nucleic acids; and the other one (P. cornucopiae and P. ostreatus), by the bands of pigments such as melanins; carotenoids; azafilones; polyketides; and flavonoids located in the cell wall. Additionally, bands corresponding to cell wall polysaccharides, particularly chitosan and 1,3-β D-glucan, were identified in the extracts of P. cornucopiae, P. ostreatus and L. edodes. No signal of cell wall polysaccharides was found in G. lucidum extract. Raman mapping of the analyzed samples was useful in tracking the spatial distribution of the marker bands. Moreover, the principal component analysis (PCA) carried out on the acquired SERS spectra, allows to discriminate the analyzed mushroom species. Conclusions The SERS technique has the ability to generate a strong Raman signal from mushroom fruiting bodies using Ag-NPs deposited directly on intact, untreated mushroom tissues. Using this methodology, commonly applied laboratory time-consuming methods can be avoided or bypassed as well as analysis time can be reduced. Graphical Abstract

Tuber borchii is a precious truffle, which forms ectomycorrhizal associations with several coniferous and broadleaf trees, arbutoid mycorrhizas with the strawberry tree and recently it was found also to form orchid mycorrhizas with Epipactis atrorubens. In this work, we investigated the formation of T. borchii mycorrhizas in other orchid species (Anacamptis morio, Cephalanthera longifolia, Limodorum abortivum, Ophrys sphegodes, Orchis purpurea). To this aim the orchids growing in three T. borchii production areas located in Emilia Romagna region (Italy) were collected and the presence of T. borchii mycorrhizas was investigated by morphological and molecular approaches. For T. borchii molecular identification, specific primers were used by a nested PCR approach. Tuber borchii was identified in 2 out of 6 samples of A. morio, 3 out of 4 samples of C. longifolia, and 2 out 6 samples of O. sphegodes. The ecological and biological roles of the orchid association in the truffle life cycle are discussed.

A genome-wide association study (GWAS) was performed as a preliminary step to identify regions potentially related to ham quality traits. In this research, genomic information was obtained from 238 commercial hybrid pigs utilising the GeneSeek® Genomic Profiler genome-wide porcine genotyping array. Carcasses were tested for hot weight, the thickness of backfat and loin, and lean meat percentage. The corresponding fresh hams were assayed for weight and ultimate pH; the activities of Cathepsin B and Ferrochelatase of Semimembranosus muscle were determined through fluorimetric methods. The lean meat percentage of fresh ham (LMPH), salt absorbed after first (SALT1) and overall salting stages (SALT) were estimated online by the Ham Inspector™ apparatus. Hams were processed in compliance with the procedures established for Protected Designation of Origin Parma ham, and ham weight losses were measured at the main processing stages. Hot carcass weights showed a significant negative correlation with their lean meat percentage and LMPH, while LMPH was correlated positively with carcass lean meat, SALT1, SALT, and weight losses. The GWAS detected genome-wide association for 12 single nucleotide polymorphisms with Ferrochelatase activity. The results obtained in this preliminary study were achieved by combining innovative and non-destructive technologies for screening hams under processing, measures of enzymatic muscle properties relevant to dry-cured ham quality, and genomic information obtained through a GWAS. Additional studies carried out in a larger number of pigs have been planned to investigate the effect of gene variants of Ferrochelatase activity in the dry-cured ham’s quality with main reference to colour development and to confirm the GWAS results obtained in this study.

Tuber melanosporum is an ascomycete that forms ectomycorrhizal (ECM) symbioses with a wide range of host plants, producing edible fruiting bodies with high economic value. The quality of seedlings in the early symbiotic stage is important for successful truffle cultivation. Numerous bacterial species have been reported to take part in the truffle biological cycle and influence the establishment of roots symbiosis in plant hosts and the development of the carpophore. In this work, three different bacteria formulations were co-inoculated in Quercus ilex L. seedlings two months after T. melanosporum inoculation. At four months of bacterial application, the T. melanosporum ECM root tip rate of colonization and bacterial presence were assessed using both morphological and molecular techniques. A 2.5-fold increase in ECM colonization rate was found in the presence of Pseudomonas sp. compared to the seedlings inoculated only with T. melanosporum. The same treatment caused reduced plant growth either for the aerial and root part. Meanwhile, the ECM colonization combined with Bradyrhizobium sp. and Pseudomonas sp. + Bradyrhizobium sp. reduced the relative density of fibrous roots (nutrient absorption). Our work suggests that the role of bacteria in the early symbiotic stages of ECM colonization involves both the mycorrhizal symbiosis rate and plant root development processes, both essential for improve the quality of truffle-inoculated seedlings produced in commercial nurseries.

Tuberaceae is one of the most diverse lineages of symbiotic truffle-forming fungi. To understand the molecular underpinning of the ectomycorrhizal truffle lifestyle, we compared the genomes of Piedmont white truffle (Tuber magnatum), Périgord black truffle (Tuber melanosporum), Burgundy truffle (Tuber aestivum), pig truffle (Choiromyces venosus) and desert truffle (Terfezia boudieri) to saprotrophic Pezizomycetes. Reconstructed gene duplication/loss histories along a time-calibrated phylogeny of Ascomycetes revealed that Tuberaceae-specific traits may be related to a higher gene diversification rate. Genomic features in Tuber species appear to be very similar, with high transposon content, few genes coding lignocellulose-degrading enzymes, a substantial set of lineage-specific fruiting-body-upregulated genes and high expression of genes involved in volatile organic compound metabolism. Developmental and metabolic pathways expressed in ectomycorrhizae and fruiting bodies of T. magnatum and T. melanosporum are unexpectedly very similar, owing to the fact that they diverged ~100 Ma. Volatile organic compounds from pungent truffle odours are not the products of Tuber-specific gene innovations, but rely on the differential expression of an existing gene repertoire. These genomic resources will help to address fundamental questions in the evolution of the truffle lifestyle and the ecology of fungi that have been praised as food delicacies for centuries.