Resistance to Elsinoë Ampelina and Expression of Related Resistant Genes in Vitis Rotundifolia Michx. Grapes

Abstract

Muscadine grapes (Vitis rotundifolia Michx) are considered as excellent genetic resources for grape breeding programs as they are known for their hardiness and resistance to pests and diseases. However, contrary to popular belief, our study indicated that not all muscadine cultivars are resistant to anthracnose disease. In order to identify a source of genetic tolerance towards anthracnose among muscadine cultivars, a series of in-situ and ex-situ experiments were conducted through strict and sensitive screening processes. Two consecutive years of field evaluation of 54 grape cultivars showed various levels of anthracnose incidence among the cultivars between a scale of 0 (tolerant) to 5 (highly-susceptible). Resistance bioassay by inoculation of different spore densities of Elsinoë ampelina on 40 cultivars presented similar results and was consistent with those obtained from the field test. A real-time PCR analysis was conducted to investigate differences of gene expression between susceptible and tolerant cultivars and to confirm results by phenotypic identification. Expression of genes encoding chalcone synthase, stilbene synthase, polygalacturonase-inhibiting protein, chitinase and lipid transfer-protein was only detected in tolerant cultivars. Resistant muscadine cultivars identified in this study could be excellent candidates for grape disease resistance breeding programs.

Incidence of grape anthracnose on different VITIS labrusca and hibrid cultivars and rootstocks combination under humid subtropical climate

“…Anthracnose progress on grape leaves was similar than levels reported in other studies (Mirica 1988;Sônego et al 2005;Louime et al 2011). Disease initially appears during sprouting, phase propitious to the anthracnose establishment because the young leaves are highly susceptible (Brook 1973;Carisse and Morissette-Thomas 2013).…”

“…Disease assessment Disease incidence was assessed between September and March 2010/2011, 2011/2012, and 2012. Disease incidence was estimated based on the number of diseased leaves per plant on 6 vines of each of the combination of cultivar Bordô, Concord and BRS Carmem grafted in Paulsen 1103, VR 043-43 and IAC 766 rootstock were randomly selected and tagged, totaling 54 plants.…”

Relations between downy/powdery mildew diseases andsome phenolic compounds in Vitis spp.

“…In addition to V. labrusca cultivars/genotypes, the study included five interspecific cultivars that may be considered resistant in terms of downy and powdery mildew (Alleweldt and Possingham, 1998;Pacifico et al, 2013;Eibach and Töpfer, 2014). Five V. vinifera cultivars and one V. rotundifolia cultivar that is also considered resistant to downy and powdery mildew were also used in the study (Olien and Hegwood, 2000;Louime et al, 2011). V. vinifera 'Italia' was used as a control due to its sensitivity to the diseases.…”

Profile of Polyphenol Compounds of Five Muscadine Grapes Cultivated in the United States and in Newly Adapted Locations in China

“…Muscadine grapes are indigenous to the southeast United States and are well-adapted to the warm, humid environment [1,2]. They have important economic value, mainly due to their resistance to Pierce’s disease ( Xylella fastidiosa ), Plasmopara viticola , and Elsinoe ampelina [3,4,5,6]. They also have multiple health benefits, including antioxidant, antiviral agents, anticancer, antibacterial, and anti-inflammatory properties [7,8,9].…”