(2021) recently found early blight dominant genetic resistance from the cross between S.

In these previous studies, resistance levels showed a continuous distribution, suggesting that there were no dominant resistance genes for early blight resistance in these populations. tarijense were identified as the most early blight resistant species from 156 accessions among 41 wild relatives of potato by Jansky et al. Jansky and Rouse (2003) found a few early blight resistant clones among 32 potato clones from interspecific hybrids. Genetic resistant resources have also been found in wild Solanum species. (2019) screened 217 old and new commercial cultivars, only 29 cultivars clustered into the resistant group. (2018) found 12 “slow blighting” cultivars among 38 cultivars in Denmark. (1995) screened 934 potato breeding clones and cultivars in Brazil, only 27 clones were identified that had less lesioned leaf area than the resistant standard cultivar. However, only a few studies have been conducted to identify early blight resistant germplasm. Genetic disease resistance is the best long-term solution for sustainable management of early blight. solani ( Wharton et al., 2012 Gudmestad et al., 2013). Repeated application of fungicides also leads to the emergence of fungicide resistance in A. Although fungicide application is the most efficient way to control early blight in potatoes ( Yellareddygari et al., 2019), its use causes concerns about environmental contamination and food safety. Yield losses by early blight can reach up to 40% without fungicide treatments ( Harrison and Venette, 1970 Teng and Bissonnette, 1985). Early blight, caused by fungus Alternaria solani, is one of the major pathogen stresses limiting potato production, especially in regions with high temperatures ( Holley et al., 1985 Edin and Andersson, 2014 Runno-Paurson et al., 2015 Tymon et al., 2016). Potato ( Solanum tuberosum L.) is one of the most important food crops in the world. The identification of these QTLs provides new insight into the genetic basis of early blight resistance and may serve as sources for marker-assisted selection for early blight resistance breeding. In 2019, six QTLs for early blight were detected two QTLs on chromosome 5 overlapped with QTLs for maturity, and the other four QTLs did not overlap with QTLs for maturity. In 2018, three QTLs for early blight were detected two of them on chromosome 5 overlapped with QTLs for maturity, and one of them on chromosome 7 was independent of maturity QTL. A genetic linkage map covering a length of 1469.34 cM with 9124 SNP markers was used for mapping quantitative trait loci (QTL) for rAUDPC and foliar maturity. A moderate negative correlation between rAUDPC and foliar maturity was detected in both years. The population was also evaluated for foliar maturity in field trials in Maine in 20. Broad sense heritability for resistance, as measured as rAUDPC, was estimated as 0.66–0.80. The population was evaluated for foliage resistance against early blight in field trials in Pennsylvania in 20 and relative area under the disease progress curve (rAUDPC) was determined. To dissect the genetic basis of early blight resistance in this clone, a full-sib tetraploid potato population including 241 progenies was derived from a cross between B0692-4 and a susceptible cultivar, Harley Blackwell, in this study. We previously identified a tetraploid potato clone, B0692-4, which is resistant to early blight. 2Genetic Improvement of Fruits and Vegetables Laboratory, US Department of Agriculture Agricultural Research Service, Beltsville, MD, United StatesĮarly blight, caused by the fungus Alternaria solani, is one of the most economically important diseases of potatoes worldwide.1Department of Plant Pathology and Environmental Microbiology, The Pennsylvania State University, University Park, PA, United States.

Early blight potato diseases