Thesis
Advancing phenotyping for evaluating sweetness of sweet cherry
Washington State University
Master of Science (MS), Washington State University
08/2020
DOI:
https://doi.org/10.7273/000004129
Handle:
https://hdl.handle.net/2376/125106
Abstract
Sweetness of sweet cherry is an important trait for this worldwide valuable fruit crop. There is a need to breed sweet cultivars because consumers are willing to pay more for sweeter fruit. Low heritability of sweetness, measured as soluble solids content (SSC), is a breeding challenge because non-genetic factors confound the evaluation of genetic potential. The objective of this study was to determine the relative magnitude of major factors influencing SSC variability in sweet cherry to determine strategies for increasing SSC heritability. Six mid-to-late season mahogany cultivars were used, primarily in the WSU Roza Research Orchard. Fruit were evaluated over two seasons in pools from three canopy positions, 4-6 fruit row size categories, and 4-6 fruit color categories. A smaller experiment examined three successive harvest dates. Fruit skin color was the most influential non-genetic factor on SSC variability, accounting for 42-52% of the observed phenotypic variability and was five times greater than the genetic effect of the cultivar. SSC greatly increased as fruit color turned darker. Fruit size and canopy position had relatively small effects on SSC (<10% phenotypic variation). SSC slightly increased with fruit size. SSC was higher in the upper canopy but there were insignificant differences between the middle and bottom canopy positions. Harvest date was also a minor influence on SSC. These results suggest strategies for phenotyping for SSC in a breeding program to improve heritability. Such a strategy includes standardizing fruit samples to a very narrow fruit color range. Additional standards of a common fruit size range of one to two row sizes and sampling fruit only from the bottom and middle canopy positions could also be useful. To further support genetic improvement for fruit quality, future studies could focus on greater genetic diversity and non-destructive indicators of fruit maturity.
Metrics
9 File views/ downloads
15 Record Views
Details
- Title
- Advancing phenotyping for evaluating sweetness of sweet cherry
- Creators
- Ugur Emre
- Contributors
- Cameron Peace (Advisor) - Washington State University, Horticulture, Department of
- Awarding Institution
- Washington State University
- Academic Unit
- Horticulture, Department of
- Theses and Dissertations
- Master of Science (MS), Washington State University
- Publisher
- Washington State University
- Identifiers
- 99900890781901842
- Language
- English
- Resource Type
- Thesis