Metabolites produced by agents of dieback of grapevine in Sicily: Lasiodiplodia mediterranea, Neofusicoccum parvum and N. vitifusiforme

Botryosphaeria dieback was recently reported in West Sicilian vineyards. The disease complex was only associated with isolates of genus Lasiodiplodia in 2007 and together with Diplodia seriata, Neofusicoccum parvum and Neofusicoccum vitifusiforme, this latest reported for the first time on Vitis vinifera in Italy. Moreover, a representative isolate of each species was inoculated on green shoots and fulfilled Koch’s postulates, although the lengths of vascular discolourations were variable depending on the species. As well as the other GTD causal agents, the expression of foliar symptoms (pale colour along the margins and between veins) was also occasional in Sicily, it was hypothesized that…

The ectomycorrhizal community of Abies nebrodensis: preliminary results

Abies nebrodensis (Lojac.) Mattei is a Critically Endangered forest tree included in Appendix I of the Bern Convention and as a priority species in Annexes II and IV of the Habitats Directive [1]. In situ and ex situ conservation strategies [2] and, more recently, a LIFE Natura project [3] allowed a marked improvement of health conditions of trees and of seedlings renewal. A first attempt to characterize the ectomycorrhizas of A. nebrodensis was carried out by Venturella & Rambelli [4]. In the frame of the activities of the II National Workshop of Ectomycorrhyza (Palermo, 2015), this paper reports the preliminary investigation carried out on the ectomycorrhyzal community of A. nebrodensis i…

Diversity of Diatrypaceae species in three Spanish grapevine producing regions.

The objective of this study was to identify species of Diatrypaceae associated with trunk diseases in three different Spanish grapevine producing regions: Albacete, Cádiz and Valencia provinces, located, respectively, in geographically distant areas of Central, South and Eastern Spain. Species identification of 71 isolates was performed using a combination of morphological characters and phylogenetic analyses based on the internal transcribed spacer regions of the rDNA (ITS) and the β-tubulin gene. Four species of Diatrypaceae were identified: Cryptovalsa ampelina was the predominant species (63.4%) followed by Eutypa lata (19.7%), Eutypella microtheca (4.2%), and Eutypella citricola (2.8%)…

Naphthalenone polyketides produced by Neofusicoccum parvum, a fungus associated with grapevine Botryosphaeria dieback

A strain of Neofusicoccum parvum isolated from declining vines was pathogenic to grapevine cultivar Inzolia in Sicily. This strain produced some metabolites in liquid medium. Crude extract, through a bio-guided purification process, yielded four naphthalenone polyketides. They were identified by comparison with spectroscopic data and optical proprieties reported in literature as: (3S, 4S)-7-ethyl-3,4,8-trihydroxy-6-methoxy-3,4-dihydro-1-(2H)-naphthalenone, (3S*, 4S*)-3,4-dihydro-3,4,8-trihydroxy-7-(1-hydroxyethyl)-6-methoxy-1-(2H)-naphthalenone, (4S)-3,4-dihydro-4,8-dihydroxy-1-(2H)-naphthalenone, named  botryosphaerones D and A, isosclerone, respectively,  and (3S*,4S*)-3,4,5-trihydroxy-1-…

Taxonomy, pathogenicity and phylogeny of fungi associated with Botryosphaeria dieback in Sicily

Since the first report of “Botryosphaeria dieback” caused by Lasiodiplodia theobromae in 2008, other Botryosphaeriaceae were found associated with declining vines in grape-growing areas of Western and Central Sicily. In a recent study, Diplodia seriata, Lasiodiplodia sp., Neofusicoccum parvum and Neofusicoccum vitifusiforme were isolated from declining grapevines. In order to fulfill Koch’s postulates and verify any genetic variability among isolates, pathogenicity, morphological, molecular and phylogenetic analyses were performed. The pathogenicity of eighteen isolates was tested by inoculating 2-year-old rooted grapevine cuttings (cv. Inzolia) and evaluating vascular discoloration length …

Primi studi su Biscognauxia mediterranea in Sicilia occidentale.

Loquat decline in Italy caused by botriosphaeriaceus fungi

A white Maitake (Grifola frondosa): nutritional value and antibacterial preliminary activity test

Grifola frondosa (Dicks.) Gray (Meripilaceae) is a big size, perennial, infrequent lignicolous basidiomycetes, traditionally known as Maitake. Brown or grayish overlapped caps, with a wavy margin, characterize the sporophore. In the wild, it is usually found at the base of living oak trees but it is also cultivated. G. frondosa is mainly distributed in Japan, Asia, Eastern America, and Europe. In Italy, is infrequent but widely distributed in all regions. Field investigation carried out in autumn 2016 in Sicily (southern Italy) permitted to observe an unusual white G. frondosa growing at the base of a living tree of Quercus pubescens Willd. s.l. Once harvested, the mushroom sample was clean…