Genomic tools revolutionize parthenocarpic blueberry breeding
image: Assessment of parthenocarpy in two southern highbush blueberry breeding populations. (A) The parthenocarpy treatment included emasculation of flowers and exclusion of pollinators for 10 flowers of each genotype to prevent any possibility of pollination or fertilization. (B) Facultative parthenocarpic genotypes yielded seedless fruits after emasculation treatment. (C) The same genotype yielded seeded fruits from open pollination in untreated flowers. (D) The raw phenotypic distribution of parthenocarpy for independent and combined populations is presented in a violin plot. (E) Pie charts illustrate the proportion of individuals in each population displaying parthenocarpic fruit set of ≥10%. Image link: https://academic.oup.com/view-large/figure/517534127/uhaf086f1.tif
Credit: Horticulture Research
Blueberry cultivation relies heavily on pollination, which can be limited by environmental factors and the availability of pollinators. This research addresses the challenges posed by such limitations by focusing on facultative parthenocarpy in blueberries, where fruit set occurs without fertilization. Despite its potential, the development of parthenocarpic blueberries has been hindered by the need for extensive breeding and phenotyping. Based on these challenges, further research is essential to optimize genomic breeding tools for this trait.
This study, published (DOI: 10.1093/hr/uhaf086) in Horticulture Research in 2025, was conducted by researchers from University of Florida and Federal University of Viçosa. The researchers performed genome-wide association studies (GWAS) on two southern highbush blueberry breeding populations to identify genetic markers linked to parthenocarpy and assessed three molecular breeding methods: genomic selection (GS), GS de novo GWAS (GSdnGWAS), and in silico marker-assisted selection (MAS).
The research identified 55 marker-trait associations linked to parthenocarpic fruit set, pinpointing genes associated with phytohormones, cell cycle regulation, and seed development. GWAS revealed specific markers on chromosomes 6, 7, and 11 that consistently showed significant associations with parthenocarpic traits across different populations. Additionally, the study compared the predictive abilities of GS, GSdnGWAS, and MAS, with GSdnGWAS outperforming the other methods, highlighting its potential for future breeding programs. The inclusion of GWAS markers in genomic selection improved prediction accuracy, offering an efficient tool for developing parthenocarpic cultivars.
"Genomic prediction models like GSdnGWAS are a game-changer for breeding programs," says Dr. Patricio R. Muñoz, lead author and professor at the University of Florida. "These tools not only help speed up the selection process but also allow us to incorporate prior genetic knowledge, ensuring better results with fewer resources."
The findings from this study open new possibilities for breeding blueberries that are more resilient to pollination deficits, especially in regions facing challenges with pollinator health and climate change. The identified markers could be used to develop more reliable and high-yielding blueberry varieties, potentially benefiting both the agricultural industry and the environment by reducing the reliance on pollination services.
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References
DOI
Original Source URL
https://doi.org/10.1093/hr/uhaf086
Funding information
This work was supported by royalties from the University of Florida Blueberry Breeding program.
About Horticulture Research
Horticulture Research is an open access journal of Nanjing Agricultural University and ranked number one in the Horticulture category of the Journal Citation Reports ™ from Clarivate, 2023. The journal is committed to publishing original research articles, reviews, perspectives, comments, correspondence articles and letters to the editor related to all major horticultural plants and disciplines, including biotechnology, breeding, cellular and molecular biology, evolution, genetics, inter-species interactions, physiology, and the origination and domestication of crops.