TY - JOUR
T1 - A polyphasic approach for the characterization of endophytic Alternaria strains isolated from grapevines
AU - Polizzotto, Rachele
AU - Andersen, Birgitte
AU - Martini, Marta
AU - Grisan, Simone
AU - Assante, Gemma
AU - Musetti, Rita
N1 - Funding Information:
This research was supported by Area Science Park (Italy) ‘Sister’ Project, by Arsia-Regione Toscana (Italy), and by Tenuta Villanova (Farra d'Isonzo, GO, Italy).
Copyright:
Copyright 2012 Elsevier B.V., All rights reserved.
PY - 2012/1
Y1 - 2012/1
N2 - A polyphasic approach was set up and applied to characterize 20 fungal endophytes belonging to the genus Alternaria, recovered from grapevine in different Italian regions.Morphological, microscopical, molecular and chemical investigations were performed and the obtained results were combined in a pooled cluster analysis. Following morphological analyses, all strains were grouped according to their three-dimensional sporulation pattern on PCA and to the colony characteristics on different substrates. After DNA extraction, all strains were analyzed by RAPD-PCR and the resulting profiles were subjected to cluster analysis. The metabolites extracted from the 20 Alternaria endophytes were analyzed by a HPLC and the resulting metabolite profiles were subjected to multivariate statistic analyses. In comparison with reference 'small-spored' Alternaria species, the 20 strains were segregated into two morphological groups: one belonging to the A. arborescens species-group and a second to the A. tenuissima species-group. RAPD analysis also showed that grapevine endophytes belonged to either the A. arborescens or the A. tenuissima species-group and that they were molecularly distinct from strains belonging to A. alternata. Chemotaxonomy gave the same grouping: the grapevine endophytic strains belong to A. arborescens or A. tenuissima species-groups producing known metabolites typical of these species-groups. Interestingly, the 20 grapevine endophytes were able to produce also a number of unknown metabolites, whose characterization could be useful for a more precise segregation of the two species-groups.The results show how complementary morphological, molecular and chemical data can clarify relationships among endophyte species-groups of low morphological divergence.
AB - A polyphasic approach was set up and applied to characterize 20 fungal endophytes belonging to the genus Alternaria, recovered from grapevine in different Italian regions.Morphological, microscopical, molecular and chemical investigations were performed and the obtained results were combined in a pooled cluster analysis. Following morphological analyses, all strains were grouped according to their three-dimensional sporulation pattern on PCA and to the colony characteristics on different substrates. After DNA extraction, all strains were analyzed by RAPD-PCR and the resulting profiles were subjected to cluster analysis. The metabolites extracted from the 20 Alternaria endophytes were analyzed by a HPLC and the resulting metabolite profiles were subjected to multivariate statistic analyses. In comparison with reference 'small-spored' Alternaria species, the 20 strains were segregated into two morphological groups: one belonging to the A. arborescens species-group and a second to the A. tenuissima species-group. RAPD analysis also showed that grapevine endophytes belonged to either the A. arborescens or the A. tenuissima species-group and that they were molecularly distinct from strains belonging to A. alternata. Chemotaxonomy gave the same grouping: the grapevine endophytic strains belong to A. arborescens or A. tenuissima species-groups producing known metabolites typical of these species-groups. Interestingly, the 20 grapevine endophytes were able to produce also a number of unknown metabolites, whose characterization could be useful for a more precise segregation of the two species-groups.The results show how complementary morphological, molecular and chemical data can clarify relationships among endophyte species-groups of low morphological divergence.
KW - Chemotaxonomy
KW - Metabolite profiling
KW - Morphology
KW - RAPD
UR - http://www.scopus.com/inward/record.url?scp=83955161064&partnerID=8YFLogxK
U2 - 10.1016/j.mimet.2011.11.009
DO - 10.1016/j.mimet.2011.11.009
M3 - Journal article
C2 - 22123507
AN - SCOPUS:83955161064
SN - 0167-7012
VL - 88
SP - 162
EP - 171
JO - Journal of Microbiological Methods
JF - Journal of Microbiological Methods
IS - 1
ER -