A recent study conducted by researchers from the University of Massachusetts Amherst and Shandong Agricultural University has made significant strides in understanding plant breeding mechanisms. Published in the journal Science on November 21, 2025, the research explores how plants recognize and interact with pollen from different species, potentially paving the way for new crop varieties.
The research focuses on a phenomenon known as “interspecific incompatibility” (ISI), which prevents pollen from distantly related species within the same family from successfully fertilizing one another. This biological barrier has posed challenges for agriculturalists seeking to breed new crop species with enhanced traits. According to Alice Cheung, a Distinguished Professor of Biochemistry and Molecular Biology at UMass Amherst, the molecular mechanisms behind ISI have remained largely elusive compared to the more understood self-incompatibility systems.
The team chose the Brassicaceae family, which includes widely consumed vegetables such as broccoli, cabbage, and kale, to investigate these mechanisms. The study reveals that during pollination, plants utilize a specific protein known as SRK to identify and reject incompatible pollen. This protein interacts with a chemical signal called SIPS, which is present on the surface of the pollen grains.
Moreover, the research highlights the role of another enzyme, FERONIA, in this process. The collaboration between SRK and SIPS recruits FERONIA, leading to the production of reactive oxygen species (ROS). This chemical reaction effectively blocks incompatible pollen from entering the pistil, the female reproductive organ where fertilization occurs.
Cheung and her team have also proposed a breeding strategy to overcome this incompatibility, which could accelerate the development of new crop varieties. The implications of this research are significant for food security, as it opens avenues for generating crops with improved traits by facilitating cross-breeding between distantly related species.
The findings emphasize the complex interactions that govern plant reproduction and highlight the potential for enhancing agricultural yields through innovative breeding practices. As the global demand for food continues to rise, such research could play a crucial role in shaping the future of crop production.
For further details, the study can be referenced: Yunyun Cao et al, “Pan-family pollen signals control an interspecific stigma barrier across Brassicaceae species,” Science, DOI: 10.1126/science.ady2347.
