An in vitro method to evaluate grapevine cultivars for Erysiphe necator susceptibility

Abstract

Powdery mildew, caused by the obligate biotrophic ascomycete Erysiphe necator, is one of the most destructive grapevine diseases worldwide. Cultivars of Vitis vinifera L, for wine and table grape production, are all susceptible to E. necator, whose attacks result in severe epidemics under the warm and dry conditions of the Mediterranean basin. The aim of the present study was to compare the susceptibility of different grapevine cultivars to E. necator by an in vitro assay for assessing the potentiality of this method in breeding programs for resistance to the pathogen. Leaves of 12 grapevine cultivars were spot-inoculated in vitro with about 10 conidia from five different isolates of E. necator, using colony growth and conidiation 3 wk post-inoculation as indicators of susceptibility to the disease. A remarkable difference was observed between highly susceptible cultivars like 'Baresana', 'Malvasia', 'Bianca', and 'Italia', and the less susceptible 'Alphonse Lavallée' and 'Ohanez', in accordance with their behavior in the field. No statistically significant differences were found in the virulence of E. necator isolates.

Comparison of Four Systems to Test the Tolerance of ‘Fortune’ Mandarin Tissue Cultured Plants to Alternaria alternata

“…In the case of intact leaves, no damage was observed, and the opposite was noticed in the wounded leaves, since above 75% of the leaves presented damage with an application of a preparation containing 75 mg L −1 of ACT. Similar results were obtained by [ 8 ] with chemically-synthesized AM-toxin I of A. alternata in in vitro leaves obtained from apple mutant shoots, and the same method was used by [ 20 ] in Vitis vinifera to evaluate the capacity of vitis cultivars to resist the Erysiphe necator infection. This protocol had not been proven in vitro in citrus plants to test them against ACT before; however, it has been extendedly used ex vitro thanks to the studies made by [ 2 ] in A. alternata pv.…”

Retracted: Variation of Phomopsis viticola isolates in the interaction with grapevine germplasm

“…In this work, we studied the pathogenic variability of Phomopsis isolates during the interaction with different grapevine cultivars by different in vitro methods. The survey strategies we adopted have been efficiently used for exploring the susceptibility of plant genotypes (Miazzi et al, 2010;Russel, 1978) and have the advantage of triggering reactions similar to in vivo responses of plants in a shorter time and minimal influence from external environmental conditions (Dami et al, 2005). Firstly, we performed artificial inoculation of in vitro-produced vines of different cultivars with two isolates of Ph.…”

“…Plants of different table grape cultivars from Apulia were in vitro propagated from axillary buds as described by Miazzi, Hajjeh, and Faretra (2010). Vitis riparia "Gloire de Montpellier" was also included in the collection as a resistant genotype.…”

Two Cu(ii)-triadimenol complexes as potential fungicides: synergistic actions and DFT calculations

“…10,11 Triadimenol, chemically named (1S,2R)-1-(4-chlorophenoxy)-3,3-dimethyl-(1,2,4-triazol-1-yl)butan-2-ol, is an important 1H-1,2,4-triazole fungicide with a broad spectrum of activity against mildews and rusts in cereals, fruits and vegetables. 12,13 This compound inhibits fungal proliferation by the interference with steroid biosynthesis and fungal cell-membrane formation mediated by cytochrome P450-dependent 14a-sterol demethylase (P450DM), an essential enzyme in ergosterol biosynthesis in fungi and cholesterol synthesis in mammalian cells. 14 However, the intensive use and single active site of triadimenol have led to the problem of the antifungal resistance.…”