Tuber borchii Vitt. mycorrhiza protects Cistus creticus L. from heavy metal toxicity

Heavy metals (HMs), such as copper, zinc, lead, mercury and cadmium, are the most abundant and dangerous inorganic environmental pollutants. Growing pieces of evidence suggest that mycorrhizal fungi can alleviate metal toxicity in plants. In this study, we focused attention on the ectomycorrhizal (ECM) fungus Tuber borchii Vitt., which is widespread in Italy and is of great ecological interest because of the mutualistic associations and the advantages it provides to host plants. Seedlings of the Mediterranean shrub Cistus creticus L., mycorrhized and non mycorrhized with the ECM fungus 7: borchii, were treated with HMs (zinc, lead and chromium). HMs induced leaves' chlorosis in non mycorrhized seedlings; while no significant differencewas observed impigmentation of mycorrhized seedlings' leaves. This observation was confirmed by Euclidean Distance of color measurements in L*a*b* units from RGB digital images of leaves. The decrease in leaves pigmentation observed in HM treated non mycorrhized seedlings strongly correlated with a reduced expression of key genes associated with chlorophyll biosynthesis; instead, no significant variation of gene expression was detected in mycorrhized seedlings treated with HMs

vacuolar sorting mechanisms are differently influenced by detoxification processes

Glyphosate is a non-selective herbicide that inhibits the shikimate pathway's enzyme EPSPS (5-enolpyruvylshikimate-3-phosphate synthase) preventing the production of aromatic amino acids. This herbicide is largely used and appreciated because it controls a wide range of annual and perennial weeds but it has a minimal environmental impact when compared with other herbicides. Initially it was thought that resistance to glyphosate was not easy to evolve but the continuous applications, as it happened for other herbicides, have induced the development of several glyphosate-resistant weeds. Glyphosate resistance can be developed as target-site and non-target-site mechanisms. In the target-site mechanism of resistance, either a mutation on the EPSPS enzyme (enzyme modification) or the overexpression of the EPSPS enzyme have been found to confer resistance. In the non-target-site mechanism of glyphosate resistance, the herbicide translocation and neutralization is observed. Pumping glyphosate into vacuoles via membrane transporters has been suggested as a possible process involved in the restricted glyphosate translocation. As a consequence, a different vacuolar organization or plasticity could be an interesting character or marker to correlate to glyphosate resistance. Vacuolar markers AleuGFP (Sar1 dependent sorting) or GFPChi (Sar1 independent sorting) respectively can be used to monitor independent vacuolar sorting mechanisms during glyphosate induced stress. We observed that the adaptive reaction of tobacco protoplasts vacuolar system to the treatment with glyphosate, can be mimicked by the overexpression of a Triticum durum TdGST gene. Previous analysis evidenced that the herbicide glyphosate increased TdGST expression, confirming the role of GST in the protection against xenobiotics. Non-target-site glyphosate resistance mechanisms may correlate with an independent regulation of cell compartmentalization and herbicide induced genes may have a direct effect on it

Xylella fastidiosa subsp. pauca (CoDiRO strain) infection in four olive (Olea europaea L.) cultivars: profile of phenolic compounds in leaves and progression of leaf scorch symptoms

Xylella fastidiosa subsp. pauca (Xfp), strain CoDiRO, infects a broad range of olive (Olea europaea L.) cultivars. The profile of phenolic compounds, progression of leaf scorch symptoms and population density of X. fastidiosa were analyzed in response to Xfp infection, in four olive cultivars (Cellina di Nardò, Ogliarola di Lecce, Frantoio and Leccino). Differences in X. fastidiosa multiplication in xylem tissues were estimated using qPCR assays, showing that cvs. Cellina di Nardò and Ogliarola di Lecce were characterized by fewer threshold cycles than for cvs. Frantoio and Leccino. Periodical visual inspections of symptomatic plants estimated disease severity and progression using a disease rating scale; cvs. Frantoio and Leccino showed some disease resistance with up to 3-fold severity scores than those for cvs. Cellina di Nardò and Ogliarola. During vegetative growth, Xfp-positive leaf samples were analyzed using HPLC-ESI–TOF–MS. Among quantified phenolic compounds, Xfp infection modified hydroxytyrosol glucoside and quinic acid. Constitutive levels of hydroxytyrosol glucoside were greater in cvs. Frantoio and Leccino compared to Cellina di Nardò and Ogliarola di Lecce, while levels were strongly reduced in infected plants (95% reduction in Cellina di Nardò, 94% in Ogliarola di Lecce, 97% in Frantoio and 98% in, Leccino). Constitutive levels of quinic acid did not differ among cultivars, but strongly increased in infected Cellina di Nardò and Ogliarola di Lecce (5-fold increases), and to a lesser extent (4-fold increases) in infected Frantoio and Leccino. These results were consistent with the previously reported positive association of quinic acid with X. fastidiosa subsp. fastidiosa symptoms and titres in grapevine. Differences in the induced responses of these phenolic compounds among cultivars suggest that they play defensive roles in olive tree response to X. fastidiosa infection

Characterization of a glutathione S-transferase in Triticum durum

none5noneE. SABELLA; A. APRILE; R.PANNA; E. NUTRICATI; L. DE BELLIS;Sabella, Erika; Aprile, Alessio; Panna, Riccardo; Nutricati, Eliana; DE BELLIS, Luig

Diversity of Crithmum maritimum L. from Salento Coastal Area: A Suitable Species for Domestication

Crithmum maritimum L., known as sea fennel, is an aromatic halophyte typical of the cliffs and coastal areas of the Mediterranean Sea and Atlantic Ocean. Their phytochemicals have been of great interest in the food and pharmaceutical industry. In this work, we analyzed, by SPME/gas chromatography coupled with mass spectrometry, the chemical variability of C. maritimum accessions in terms of volatile organic compounds. C. maritimum seeds were collected from different coastal sites in Salento, Southern Apulia, Italy, and subsequently cultivated ex situ. Several volatile compounds produced by C. maritimum leaves were detected, and, among them, D-limonene was found to be emitted at high levels by plants of all accessions representing the main compound, while other monoterpenes were produced at low levels. Moreover, the phenylpropene volatiles dillapiol and apiol (designated together as (dill)apiol) were emitted at variable amounts with different accessions. The correlation among groups based on volatile compounds has been analyzed using hierarchical cluster analysis, which has revealed three main groups based on (dill)apiol presence and its total amount in the cultivated plants of different geographic origins, confirming intraspecies biodiversity. Moreover, we have evaluated the seed germination and seedling development of C. maritimum in controlled conditions. We found no dormancy and a high germination rate for all samples analyzed. The chemo-diversity evidenced in cultivated plants obtained from seeds collected at different locations on the Salento peninsula is probably related to variations in climate resulting from different exposures along the coast. These findings highlighted the importance of C. maritimum as a suitable candidate for cultivation because it can tolerate harsh conditions/stresses and also has a possible use besides food and pharmaceuticals and for the restoration of coastal environments

Antitumor and antimigration effects of Salvia clandestina L. extract on osteosarcoma cells

none6noSalvia clandestina L. is a wild perennial species present in the Salento area of Italy. Here, we examined the in vitro effects of an aqueous extract of S. clandestina L. on the MG-63 osteosarcoma cell line. The extract reduced osteosarcoma cell viability mainly by way of apoptosis, as we observed (1) upregulation of gene and protein expression of p53, cyclin-dependent kinase inhibitors p21(WAF1) and p27(Kip1), and proapoptotic BAX; (2) activation of caspases; and (3) induction of a sub-G(1) peak in the cell cycle. The mitogen-activated protein kinases (MAPKs) JNK1/2 and p38 are activated and involved in the intracellular effects of the S. clandestina extract, as preincubation with the JNK1/2 inhibitor SP600125 or the p38 inhibitor SB203580 significantly decreased S. clandestina extract-induced cytotoxicity and inhibited increase in p53, p21(WAF1), p27(Kip1), and BAX. SP600125 also inhibited mRNA levels for all the aforementioned proteins, while SB203580 only affected p53 mRNA. Furthermore, S. clandestina extract treatment counteracted epithelial-to-mesenchymal transition, inhibited cell migration, and decreased the expression and activity of matrix metalloproteinase MMP2. In addition, S. clandestina extract enhanced the cytotoxic activity of cisplatin on MG-63 cells through downregulation of the Akt/PKB protein kinase. We conclude that S. clandestina extract may be a novel agent for osteosarcoma treatment.noneAntonella Muscella; Erika Stefàno; Luigi De Bellis; Eliana Nutricati; Carmine Negro; Santo MarsiglianteMuscella, Antonella; Stefano, Erika; DE BELLIS, Luigi; Nutricati, Eliana; Negro, Carmine; Marsigliante, Sant

Arthrinium phaeospermum isolated from Tuber borchii ascomata: the first evidence for a “Mycorrhization Helper Fungus”?

A filamentous fungus was isolated from Tuber borchii Vitt. fruiting bodies, and it was identified as an Arthrinium phaeospermum (Corda) M.B. Ellis strain, an “endophyte” that forms various associations with healthy leaves, stems, and roots of plants. Molecular analysis confirmed the association of this filamentous fungus with the ascocarps of all collection sites in Salento, Apulia (South Italy). An in vitro symbiosis system between Cistus creticus L. and T. borchii was set up; A. phaeospermum appears to be able to promote mycorrhiza formation in Cistus seedlings, inducing primary root shortening and an increase of secondary roots, similar to the effect of Mycorrhization Helper Bacteria (MHB). Compartmented and uncompartmented bioassays were carried out to investigate the effects of exudates/volatiles released by the truffle-hosted fungus on root architecture; the results showed root shortening in compartmented bioassay suggesting that volatiles released by the fungus alone are sufficient to alter root morphology in early phase of interaction before the mycorrhiza formation. The first evidence for an influence of a truffle-hosted fungus on ectomycorrhizal symbiosis establishment is reported

Influence of environmental factors on essential oil variability in thymbra capitata (l.) cav. Growing wild in southern puglia (Italy)

none7nononeTommasi, Luca*; Negro, Carmine; Cerfeda, Antonio; Nutricati, Eliana; Zuccarello, Vincenzo; De Bellis, Luigi; Miceli, AntonioTommasi, Luca; Negro, Carmine; Cerfeda, Antonio; Nutricati, Eliana; Zuccarello, Vincenzo; De Bellis, Luigi; Miceli, Antoni