Pears, among the oldest domesticated fruit trees, are the focus of a new study that reveals significant insights into their genetic variations and the implications for breeding practices. Research conducted by a collaborative team from Shandong Agricultural University, Nanjing Agricultural University, and the Zhongshan Biological Breeding Laboratory has unveiled how genetic alterations have enabled pears to adapt to diverse climatic conditions. Their findings, published in Horticulture Research in May 2025, provide a framework for breeding more resilient and high-quality pear varieties.
The research team analyzed over 9 million SNPs across 232 pear accessions to investigate the genetic impact of domestication on deleterious mutations. This study is particularly important as previous research primarily focused on annual crops, leaving a gap in understanding genetic patterns in perennial species like pears. The investigation uncovered a total of 9,909,773 SNPs, with 139,335 identified as deleterious mutations, predominantly concentrated in coding regions. Notably, these mutations were found to be more frequent in Pyrus communis, the European pear, compared to other species.
Key Genetic Discoveries in Pear Domestication
The researchers highlighted selective sweep regions indicating that domestication has reduced deleterious mutations in Pyrus pyrifolia and Pyrus bretschneideri, while an increase in such mutations in P. communis likely resulted from genetic drift during the domestication process. The study also identified the critical role of the PyMYC2 gene, which is linked to stone cell formation in pears. Overexpression of this gene in pear callus cultures led to increased lignin and stone cell content, making it a key target for breeders aiming to improve 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. The identification of PyMYC2 as a regulator of stone cell content is a breakthrough that could significantly inform future breeding strategies.”
Implications for Future Breeding Programs
The discovery of deleterious mutations and their associations with agronomic traits in pears carries important implications for breeding programs. By focusing on genes like PyMYC2, breeders can develop new pear varieties that optimize desirable traits, such as enhanced texture and improved disease resistance. Furthermore, the findings suggest that employing modern molecular breeding techniques, such as genome-wide selection, can mitigate the accumulation of harmful mutations in cultivated varieties.
These advancements are critical for meeting the rising global demand for high-quality pears and enhancing crop resilience in response to climate change. The research highlights the need for further studies to explore the genetic underpinnings of these mutations, ultimately paving the way for improved pear varieties that can thrive in changing environmental conditions.
The work was supported by several funding bodies, including the National Science Foundation of China and the National Key Research and Development Program of China, reflecting the importance of this research in the broader context of agricultural innovation.
For further details, the full study can be accessed at DOI: 10.1093/hr/uhaf140.
