Several species of Botr yosphaeria are known to occur on grapevines, causing a wide range of disorders including bud mortality, dieback, brown wood streaking and bunch rot. In this study the 11 Botryosphaeria spp. associated with grapevines growing in various parts of the world, but primarily in South Africa, are distinguished based on morphology, DNA sequences (ITS-1, 5.8S, ITS-2 and EF1-␣) and pathological data.

Black foot disease of grapevines is a decline and dieback disease caused by a soilborne pathogen complex including Cylindrocarpon liriodendri , C. macrodidymum , Campylocarpon fasciculare and Campyl. pseudofasciculare . These pathogens cause primary infections of roots and basal ends of grafted cuttings in nursery soils. Thirteen fungicides were screened in vitro for mycelial inhibition of these pathogens. Prochloraz manganese chloride, benomyl, flusilazole and imazalil were the most effective fungicides tested, and were subsequently included in semi-commercial field trials. Basal ends of grafted cuttings were dipped in various chemical and biological treatments prior to planting in open-rooted nurseries. Black foot pathogens were not isolated from grafted cuttings prior to planting. Additional treatments involved soil amendments with Trichoderma formulations and hot water treatment of dormant nursery grapevines. Field trials were evaluated after eight months. Isolations from uprooted plants revealed low levels of black foot pathogens in the roots of untreated control plants, and significantly higher levels in basal ends of rootstocks. The incidence of black foot pathogens, as well as that of Petri disease pathogens, was not significantly and/or consistently reduced by the majority of chemical or biological treatments. However, these pathogens were not isolated from uprooted plants that were subjected to hot water treatment. It is therefore recommended that hot water treatment of dormant nursery plants be included in an integrated strategy for the proactive management of these diseases in grapevine nurseries.

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Black foot disease is a serious disease of grapevine crops in most areas where vines are grown. Mainly two species of Cylindrocarpon, C. destructans and C. macrodidymum, are associated with this disease. Recent studies have revealed a tremendous molecular variation within the former but only slight molecular variation within the latter, indicating that C. destructans presents a complex of several species The present study elucidates the taxonomic status of C. destructans-like isolates associated with black foot disease of grapevines. Grapevine isolates were studied morphologically, subjected to DNA analyses of their ITS and partial β-tubulin genes, and were mated in all combinations in vitro. Cylindrocarpon destructans strains isolated from grapevines in Europe and South Africa appeared morphologically and genetically identical, and had identical ITS and partial β-tubulin gene sequences. Phylogenetic analyses placed these strains in a clade closely related but clearly distinct from other clades with C. destructans-like anamorphs obtained from various herbaceous or woody hosts. Only the ex-type strain of Cylindrocarpon liriodendri had identical sequences to strains isolated from grapevines, and could also not be distinguished by morphological characters. The grapevine isolates are therefore reidentified here as Cylindrocarpon liriodendri. Cylindrocarpn liriodendri formed perithecia in heterothallic conditions and the holomorph of this species is described as Neonectria liriodendri sp. nov. Neonectria liriodendri is genetically distinct from the ex-type strain of Neonectria radicicola, which originated from Cyclamen in Sweden. Both ex-type strains also differ from at least two other clades comprising additional C. destructans-like strains. Many of these strains originated from Panax sp., which is the host of the type of C. destructans. Our phylogenetic analyses indicate that C. destructans is not the anamorph of N. radicicola and that N. liriodendri, N. radicicola and several C. destructans-like taxa may have evolved independently within the same phylogenetic species complex.

This paper represents the second contribution in the Genera of Phytopathogenic Fungi (GOPHY) series. The series provides morphological descriptions and information regarding the pathology, distribution, hosts and disease symptoms for the treated genera. In addition, primary and secondary DNA barcodes for the currently accepted species are included. This second paper in the GOPHY series treats 20 genera of phytopathogenic fungi and their relatives including: Allantophomopsiella, Apoharknessia, Cylindrocladiella, Diaporthe, Dichotomophthora, Gaeumannomyces, Harknessia, Huntiella, Macgarvieomyces, Metulocladosporiella, Microdochium, Oculimacula, Paraphoma, Phaeoacremonium, Phyllosticta, Proxypiricularia, Pyricularia, Stenocarpella, Utrechtiana and Wojnowiciella. This study includes the new genus Pyriculariomyces, 20 new species, five new combinations, and six typifications for older names.

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Petri disease is a vascular disease associated with decline and dieback of young grapevines. A major means of spread of the causal organisms, Phaeomoniella chlamydospora and Phaeoacremonium spp., is via infected propagation material. Since no curative control measures are known, proactive measures must be taken in grapevine nurseries to manage this disease. To study this aspect, semicommercial trials with naturally infected rootstock material were performed in grapevine nurseries in South Africa. Prior to grafting, rootstocks were treated as follows: 1-h drench in suspensions of benomyl, phosphoric acid, different bacterial and Trichoderma formulations, water, or hot water treated (HWT; 30 min at 50°C). Grafted cuttings were planted and grown in a greenhouse and two commercial field nurseries and uprooted 8 months later. In instances where rootstocks were treated with benomyl or Trichoderma formulations, the incidences of Phaeomoniella and Phaeoacremonium in grafted cuttings and uprooted nursery vines were significantly lower than that of the water treatment. However, the reduction was most consistent and noteworthy in vines on rootstocks that received HWT prior to grafting. HWT of dormant nursery vines effected a similar reduction in Phaeomoniella and Phaeoacremonium incidence. Root-stock drenches in benomyl and/or Trichoderma formulations could thus be integrated with HWT for the proactive management of Petri disease in grapevine nurseries.