Andrew R. Jamieson
Andrew R. Jamieson and Katherine Sanford
Twelve clones of `Blomidon' strawberry (Fragaria xananassa) exhibiting a range of severity of June Yellows symptoms were grown in field plots to measure effects on productivity. Field plot layout was a randomized block design with four blocks. Plots were matted rows developed from five plants spaced at 45 cm inrow. Fruit samples were frozen and later analyzed for soluble solids concentration, total acidity, and pH. In the greenhouse, self-pollinated seedlings grown from these clones were rated for symptom expression as an additional measure of severity of June Yellows. Large differences in marketable yields were recorded, ranging from 1.94 t·ha–1 to 14.67 t·ha–1. Clones with severe symptoms produced smaller fruit. Small clonal differences were measured in total acidity and pH. A strong correlation was observed between the percentage of symptomless seedlings and the yield of the parental clone. This may lead to a test to predict whether a new cultivar will succumb to June Yellows.
Andrew R. Jamieson and Katherine A. Sanford
Clones of `Blomidon' strawberry (Fragaria × ananassa Duch.) exhibiting a range of June yellows symptoms were grown in field plots to measure effects on productivity and fruit characteristics. Self-pollinated seedlings grown from these clones were evaluated for symptom expression as an additional measure of severity of June yellows. Large differences in yields were recorded among clones, ranging from 1.9 to 14.7 t·ha–1 in 1994 and 8.4 to 28.3 t·ha–1 in 1995. Clones with severe symptoms produced smaller fruit than clones with slight symptoms in 1994 but not in 1995. Small differences existed for the titratable acidity of the fruit but not for soluble solids concentration. The frequency of normal green seedlings among selfed progeny ranged from 48% to 98% and was negatively correlated with symptom severity ratings of the parent clones. Severity ratings and selfed seedling abnormality rates were good predictors of fruit yield. No clones of `Blomidon' were free of June yellows.
Andrew R. Jamieson, Kevin R. Sanderson and Roger J.A. Tremblay
Karen L. Burgher, Andrew R. Jamieson and Xuewen Lu
Twenty-six genotypes of lowbush blueberry (Vaccinium angustifolium Aiton) representing four geographical zones (Maine, United States; New Brunswick, northern Nova Scotia, and western Nova Scotia, Canada) were selected to obtain DNA fingerprints and to estimate genetic similarity by randomly amplified polymorphic DNA analysis. The genotypes were either native accessions or selections from crosses involving native accessions as parents or grandparents. Thirty 10-base RAPD primers were initially screened; 11 proved to be polymorphic, resulting in 73 consistent RAPD bands. All 26 genotypes could be distinguished by their unique RAPD banding patterns and three unlabeled samples were correctly identified. The RAPD band data set was analyzed with Genstat5 to calculate similarity and distance matrices. Average similarity across all genotypes was 56%. Results from average linkage cluster analysis were used to construct a dendogram which demonstrated six main clusters with an average similarity linkage of 70%. The selection `Fundy' and its parent `Augusta' clustered at 77% similarity. The corresponding principal coordinate analysis supported the clusters and identified two distinct outliers. There was a small association by geographic grouping for five genotypes from Maine. It was concluded that RAPD analysis is a useful tool for genotypic identification and estimates of genetic similarity in lowbush blueberry.