The New Cranberry Wisconsin Research Station: Renovation Priorities of a 'Stevens' Cranberry Marsh Based on Visual Mapping, Genetic Testing, and Yield Data.

Cultivar contamination is a common issue in commercial cranberry production. Unknown or unwanted cranberry genotypes are found in commercial cranberry beds that are intended to be a single uniform genotype. Identification of contamination and the impacts of contamination remain crucial issues to the cranberry industry to maintain long-term high productivity. To address this issue, tissue samples were taken from the former commercial beds of the new Wisconsin Cranberry Research Station (WCRS) for genetic fingerprinting analysis. The goals of this collection were to analyze the ten beds for genetic uniformity to determine if any should be maintained or replaced, and to assess the accuracy of visual perception of genetic contamination in the field. A total of 288 DNA samples were collected in the ten cranberry beds, and the 'Stevens' cultivar represented 180 samples, or 69% of the 261 samples expected to be 'Stevens'. Therefore, genotype contamination in the 'Stevens' beds was 31% overall. Overall, visual differentiation was accurate in distinguishing between genotypes and detecting large areas of contamination. A yield analysis was conducted along with the genotypic uniformity assessments, and a significant correlation was found between the 2017 yield of the beds and their level of genetic contamination. This study demonstrates the usefulness of genetic uniformity testing and mapping for cranberry bed management and renovation decision-making.

The Genetic Diversity of Cranberry Crop Wild Relatives, Vaccinium macrocarpon Aiton and V. oxycoccos L., in the US, with Special Emphasis on National Forests.

Knowledge of the genetic diversity in populations of crop wild relatives (CWR) can inform effective strategies for their conservation and facilitate utilization to solve agricultural challenges. Two crop wild relatives of the cultivated cranberry are widely distributed in the US. We studied 21 populations of Vaccinium macrocarpon Aiton and 24 populations of Vaccinium oxycoccos L. across much of their native ranges in the US using 32 simple sequence repeat (SSR) markers. We observed high levels of heterozygosity for both species across populations with private alleles ranging from 0 to 26. For V. macrocarpon, we found a total of 613 alleles and high levels of heterozygosity (HO = 0.99, HT = 0.75). We also observed high numbers of alleles (881) and levels of heterozygosity (HO = 0.71, HT = 0.80) in V. oxycoccos (4x). Our genetic analyses confirmed the field identification of a native population of V. macrocarpon on the Okanogan-Wenatchee National Forest in the state of Washington, far outside the previously reported range for the species. Our results will help to inform efforts of the United States Department of Agriculture Agricultural Research Service (USDA-ARS) and the United States Forest Service (USFS) to conserve the most diverse and unique wild cranberry populations through ex situ preservation of germplasm and in situ conservation in designated sites on National Forests.