Researchers Find Hornworts Could Help Turbocharge Crop Yields

Researchers at the Boyce Thompson Institute (BTI), Cornell University, and the University of Edinburgh have discovered a molecular trick in hornworts, a unique group of land plants, that could dramatically increase the efficiency of photosynthesis in major crops like wheat and rice. The study focuses on Rubisco, the critical enzyme responsible for capturing carbon dioxide, which is notoriously slow and often mistakenly reacts with oxygen.

While some algae use specialized compartments called pyrenoids to concentrate CO2 around Rubisco, transfer to land plants has proven difficult. Hornworts, however, are the only land plants with similar CO2-concentrating mechanisms, making them a more compatible biological blueprint for agricultural engineering. The breakthrough, published in Science, identifies a specific protein component, RbcS-STAR, that acts like molecular velcro. Unlike other organisms that use separate proteins to bundle Rubisco together, hornworts have modified the Rubisco enzyme itself with a small tail that causes the proteins to automatically cluster into dense, efficient compartments.

In experimental trials, the researchers successfully attached this STAR tail to the Rubisco of the model plant Arabidopsis and observed the enzyme reorganizing into concentrated, pyrenoid-like structures. This suggests that a single genetic tweak could potentially "turbocharge" the photosynthetic process across various plant systems. If successfully integrated into food crops, this discovery could boost yields by up to 60% without requiring additional land or synthetic fertilizers. By making Rubisco more efficient, plants would no longer need to breathe as deeply to capture CO2. As the global population grows and climate change threatens traditional farming, this tiny, overlooked plant offers a vital path toward more sustainable and productive agriculture.

For more details, read the article on the BTI website.