Determination of downy and powdery mildew resistance of some Vitis spp.

Abstract

The Black Sea region of Turkey receives an annual rainfall of 2000-2500 mm and viticulture in the region depends on the rainfall limits significantly. In this study, the resistance of eighty different Vitis species and cultivars/genotypes to downy and powdery mildew was assessed using Marker Assisted Selection coupled with inoculation observations. Six Simple Sequence Repeats (SSR) and one Sequence Characterized Amplified Region (SCAR) markers were developed for different resistance loci (Run1, Rpv1, Ren1, Rpv3, Ren3) from different Vitis genetic resources. Eight of the cultivars/genotypes were characterised as resistant to downy mildew, seven were resistant to powdery mildew, and four were resistant to both diseases. These results, taken together with the disease inoculation observations, revealed ‘Köfteci Üzümü’ (Vitis labrusca) and ‘Giresun 3’ (Vitis labrusca) were the most resistant cultivars/genotypes.

Mono-Locus and Pyramided Resistant Grapevine Cultivars Reveal Early Putative Biomarkers Upon Artificial Inoculation With Plasmopara viticola

“…DM affects the members of the family Vitaceae and in particular the cultivated species Vitis vinifera and it can attack all green parts of the vine (leaves, fruits, and shoots in particular) (Buonassisi et al, 2018;Vezzulli et al, 2018). DM infection leads to significant crop losses due to defoliation and to the production of lowquality, deformed or entirely damaged grapes (Yildirim et al, 2019;Nogueira Júnior et al, 2020). The most distinctive signs of infection are the sporangia formation apparent as whitish spots, commonly found on the abaxial surface of the first-formed leaves, which are accompanied by chlorotic spots (known also as oil spots) on the adaxial surface.…”

“…The application of large amounts of fungicides is the most diffused strategy to control DM, this practice, however, is not only expensive and in conflict with the requirements for sustainable and environment-friendly agriculture, but also promotes the emergence of fungicide-resistant strains (Buonassisi et al, 2018;Merdinoglu et al, 2018;Yildirim et al, 2019). A possible alternative to the use of fungicides is the valorization of the interspecific hybrids of V. vinifera with resistant genotypes from Muscadinia, several wild North American and Asian Vitis species which have been found resistant against P. viticola (Buonassisi et al, 2017;Merdinoglu et al, 2018;Vezzulli et al, 2018;.…”

Marker assisted selection (MAS) for downy mildew resistance in grapevines using Rpv3.1 associated markers

“…(2007) stated that the frequency of Lr34/Yr18 rust-resistance genes increased from 0.25 to 0.60 with MAS in BC1 wheat population, reported, however, the increase as from 0.25 to only 0.27, and claimed that it resulted from the actually poor relationship between Lr34/Yr18 genes and the markers used in the scanning of BC1 plants (Bernardo, 2008). Similarly, Yıldırım et al (2019) determined that some grapevine genotypes collected from the Black Sea coast with high humidity and precipitation, which they determined to have resistance-associated alleles as a result of MAS, showed intense mildew symptoms after artificial inoculation. Researchers point out the importance of validating the results of the marker used for MAS with the results of artificial/natural inoculation.…”

New Perspectives in Grapevine (Vitis spp.) Breeding

“…According to the studies conducted by the researchers so far, 31 genomic regions have been associated with downy mildew resistance (Rpv loci) and 13 with powdery mildew disease resistance (Run/Ren loci) (Figure 3). In order to determine the presence of these loci in hybrid genotypes, marker-assisted selection (MAS) studies have been successfully performed [76][77][78][81][82][83][84].…”