|DAVERDIN, GUILLAUME - Rutgers University|
|JOHNSON-CICALESE, JENNIFER - Rutgers University|
|VORSA, NICHOLI - Rutgers University|
Submitted to: Molecular Breeding
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/8/2017
Publication Date: 3/11/2017
Citation: Daverdin, G., Johnson-Cicalese, J., Zalapa, J.E., Vorsa, N., Polashock, J.J. 2017. Mapping and identification of fruit rot resistance QTL in American cranberry using GBS. Molecular Breeding. doi: 10.1007/s11032-017-0639-3.
Interpretive Summary: Cranberry sustainability is threatened by widespread and increasing losses due to pathogens that cause fruit rot in the field. To reduce the need for applying chemicals to control fruit rot, we are developing new disease resistant varieties. We identified cranberry plants that were naturally resistant to fruit rot but were unsuitable for commercial production. These plants were crossed with commercially acceptable varieties that lacked resistance. The populations that were developed were utilized to identify molecular markers associated with the genes that confer fruit rot resistance. We identified one of the genes responsible for resistance and are using that information to identify additional resistance genes that can be used by plant breeders to develop new fruit rot resistant varieties. New fruit rot resistant varieties that have all of the other desired traits to be commercially acceptable will increase profitability for growers and benefit the environment and consumers through the reduced use of potentially harmful chemicals.
Technical Abstract: Cranberry sustainability is threatened by widespread and increasing losses due to fruit rot in the field. Breeding for resistance is challenging because fruit rot is caused by a complex of pathogenic fungi that can vary by location and from year to year. However, we identified four genetically diverse accessions that have broad-spectrum fruit rot resistance when grown under field conditions. Three of these accessions were used in biparental crosses to develop populations segregating for resistance. Genotyping by sequencing was used to generate SNP markers for development of high density genetic maps and QTL analyses. A QTL associated with fruit resistance was discovered on Vm8. This QTL was found to explain 22% of the resistance. Another QTL for fruit rot resistance that was described previously was confirmed. The populations describe herein were phenotyped for a number of other horticulturally important traits. QTL were also identified that are associated with yield and fruit weight. These QTL can be used as markers for candidate gene discovery and for future breeding efforts to incorporate and pyramid disease resistance and other traits into elite horticultural backgrounds.