Research conducted by a collaborative team from Shandong Agricultural University, Nanjing Agricultural University, and the Zhongshan Biological Breeding Laboratory has provided significant insights into the genetic variations of pears, a fruit tree with a long history of domestication. This study, published in Horticulture Research in May 2025, explores the genetic diversity and mutation patterns found in various pear species, aiming to enhance breeding processes for more resilient and high-quality varieties.
The research team analyzed over 9 million single nucleotide polymorphisms (SNPs) across 232 pear accessions, revealing crucial information about the genetic impact of domestication on deleterious mutations. These findings are vital for understanding how genetic alterations can be harnessed to improve pear breeding. The study identified a total of 9,909,773 SNPs, with 139,335 classified as deleterious mutations, predominantly located in coding regions. Notably, the analysis indicated a higher frequency of these mutations in Pyrus communis, the European pear, compared to other species.
Key Findings on Genetic Mutations
The research uncovered selective sweep regions where domestication had reduced the presence of deleterious mutations in P. pyrifolia and P. bretschneideri. Conversely, an increase in such mutations was observed in P. communis, likely attributed to genetic drift during the domestication process. This information is crucial for future breeding strategies, as it delineates the genetic landscape that influences key agronomic traits.
A significant highlight of the study is the identification of the PyMYC2 gene, linked to stone cell formation in pears. The overexpression of this gene in pear callus cultures resulted in increased lignin and stone cell content, marking it as a pivotal target for breeding efforts aimed at enhancing pear texture. According to Professor Jun Wu from Nanjing Agricultural University, “This research provides valuable genomic insights into pear domestication, particularly in understanding how deleterious mutations shape agronomic traits.”
Implications for Future Breeding Programs
The discovery of deleterious mutations and their connections to agronomic traits carries significant implications for pear breeding programs. By targeting genes such as PyMYC2, breeders can develop new pear varieties with optimized traits, including improved texture and disease resistance. The study suggests that modern molecular breeding techniques, including genome-wide selection, can help mitigate the accumulation of harmful mutations in cultivated varieties.
These developments are critical as the global demand for high-quality pears continues to rise, particularly in the context of climate change and the need for more resilient crop varieties. The findings from this research not only enhance the understanding of pear genetics but also pave the way for innovations in breeding practices that could lead to healthier and more productive pear crops.
The research was supported by various funding sources, including the National Science Foundation of China and the National Key Research and Development Program of China. The full study can be accessed via the DOI: 10.1093/hr/uhaf140.
As the field of horticulture continues to evolve, these insights represent a significant step forward in the quest to enhance fruit quality and adaptability, ensuring that future generations can enjoy the benefits of improved pear varieties.
