Growing taller: how genetics could transform chrysanthemum breeding
image: Genome-wide selective sweep analysis by comparing the tall and short groups. The horizontal lines represent the threshold values of the top 1% of FST (a) and π ratios (b). Candidate genes related to hormones and highly expressed in shoot apexes are marked with arrows.
Credit: Horticulture Research
A new study has uncovered critical genetic factors that influence the height of chrysanthemum plants, a key trait that affects both their market appeal and structural integrity. The research analyzed plant height, internode number, internode length, and stem diameter in 200 chrysanthemum varieties. By identifying essential genetic markers, the scientists aim to equip breeders with tools to cultivate chrysanthemums that are not only visually appealing but also more robust.
Chrysanthemums are highly prized ornamental plants known for their rich diversity in flower forms and colors. Plant height is a vital determinant of both quality and commercial value, especially in cut chrysanthemums. Traditionally, height has been managed using growth regulators, which are resource-intensive and pose environmental risks. Given these challenges, a deeper understanding of the genetic foundation controlling plant height is necessary to drive more sustainable and precise breeding efforts.
The study (DOI: 10.1093/hr/uhad236), led by researchers from Nanjing Agricultural University’s State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, was published in Horticulture Research on November 14, 2023. The research team performed a genome-wide association study (GWAS) and selective sweep analysis on 200 chrysanthemum accessions. They identified 42 significant genetic associations related to plant height and its contributing traits, providing valuable markers for future breeding programs aimed at optimizing plant architecture.
The researchers found extensive variation in height-related traits across different environments and identified key SNPs, including Chr1 339370594 and Chr18 230810045, linked to plant height and stem diameter. These regions were under selective pressure, indicating their importance in height regulation. Candidate genes involved in hormonal pathways, growth processes, and metabolic regulation were also highlighted. Genomic predictions based on these findings showed high accuracy (0.94–0.97), offering promising applications in breeding programs focused on developing chrysanthemums with ideal height traits and improved cultivation efficiency.
Dr. Fei Zhang, the lead researcher from Nanjing Agricultural University, commented, “This research significantly deepens our understanding of the genetic drivers behind chrysanthemum height. The genomic markers identified will help breeders better predict and select optimal height traits. This advancement provides practical tools for the industry and opens new possibilities for breeding resilient, high-quality chrysanthemums.”
The implications of this study are far-reaching for the chrysanthemum breeding industry. By utilizing these genetic markers, breeders can more accurately select ideal height traits, reducing reliance on chemical growth regulators and promoting more sustainable cultivation. The high predictability of these markers allows for shorter breeding cycles, enabling faster development of new varieties. Ultimately, this research is expected to enhance both the quality and commercial value of cut chrysanthemums, benefiting growers and consumers alike.
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References
DOI
Original Source URL
https://doi.org/10.1093/hr/uhad236
Funding information
This work was financially supported by the National Natural Science Foundation of China (32171857), China Agriculture Research System (CARS-23-A18), Jiangsu Agriculture Science and Technology Innovation Fund (CX(21)2004), and the Priority Academic Program Development of Jiangsu Higher Education Institutions.
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, 2022. 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.