An isolate morphologically and phylogenetically distinct from Botrytis cinerea obtained from withered grapes possibly represents a new species of Botrytis

Abstract

Grapes kept after harvest for withering in drying fruit rooms (fruttaio) are highly susceptible to Botrytis cinerea infection. A taxonomically undefined isolate (B83) was identified during a survey of B. cinerea populations in these specific environments. This isolate yielded negative results in B. cinerea-specific PCRs and displayed a different colony morphology on potato dextrose agar. Based on this data, the isolate underwent a taxonomic investigation. Sequencing of the ITS-5Á8S-ITS2 region indicated that the isolate belongs to the Botrytis genus. IGS-RFLP analysis revealed that Botrytis sp. B83 was a different haplotype from genotypes of indigenous B. cinerea strains. Comparative sequence analysis of three housekeeping genes, G3PDH, HSP60 and RPB2, showed that the isolate constitutes a taxon related to Botrytis aclada, distant from B. cinerea. A phylogenetic tree built with NEP genes was in agreement with the combined tree built with G3PDH, HSP60 and RPB2 sequences. Botrytis sp. B83 is morphologically similar to B. aclada. Conversely, its host range indicates that it is polyphagous like B. cinerea, despite its lower virulence. This study provides evidence for the existence of a new species of Botrytis. Nevertheless, the description of only a single isolate and the need for further information on genetic divergence, reproductive isolation and host preference, prevent the classification and formal description of a new taxon.

Identification and characterization of Botrytis medusae, a novel cryptic species causing grey mould on wine grapes in Australia

“…Clade I includes the isolates from group I and II species B. californica , B. calthae , B. cinerea , B. eucalypti , B. fabae , B. pelargonii , B. pseudocinerea and B. sinoviticola . Recently, a new clade II Botrytis species, B. euroamericana , was found on grapevine in Italy (Lorenzini & Zapparoli, ; Garfinkel et al ., ).…”

“…Several studies have shown that B. cinerea exists within a morphologically cryptic species complex (Giraud et al, 1997(Giraud et al, , 1999Albertini et al, 2002;Fournier et al, 2003Fournier et al, , 2005Walker et al, 2011;Lorenzini & Zapparoli, 2014;Liu et al, 2016;Garfinkel et al, 2017). Distinguishing different Botrytis species in sympatry and defining their contributions to disease could assist in adapting control strategies (Walker, 2016).…”

“…Botrytis species have been previously divided into two clades, clade I and clade II. Clade I species exclusively infect eudicots, while clade II species infect monocots and eudicots (Staats et al, 2005) (Lorenzini & Zapparoli, 2014;Garfinkel et al, 2017).…”

Isolation of Neofusicoccum parvum from withered grapes: strain characterization, pathogenicity and its detrimental effects on passito wine aroma

“…Genomic DNA from pure cultures of the nine isolates was extracted according to Lorenzini and Zapparoli (). Restriction fragment length polymorphism (RFLP) of the internal transcribed spacer (ITS) region of the rDNA using the primers ITS1 and NL4 was performed on nine isolates as described by Alves et al .…”

Gray mold caused by Botrytis cinerea limits grape production in Chile

“…This Lorenzini and Zapparoli, 2014;Walker et al, 2011;Zhou et al 2014). Similarly, phylogenetic analysis suggests the presence of cryptic species in B. cinerea from stone fruits in Chile (Ferrada et al, 2014).…”