The Discovery of a 'Booster' Gene that Improves Photosynthesis Could Revolutionise Crop Cultivation

The study, titled An Orphan Gene BOOSTER Enhances Photosynthetic Efficiency and Plant Productivity, was published in Developmental Cell and was a collaboration between the Center for Advanced Bioenergy and Bioproduct Innovation at the University of Illinois and the Oak Ridge National Laboratory's Bioenergy Science Center in California.

Researchers focused on Populus trichocarpa, also known as black poplar, a tree which grows from Baja California to northern Canada. This gene led to a substantial increase in plant height by optimising solar energy capture and improving carbon assimilation.

This species is often considered a promising candidate for the production of biofuel and other useful materials. It was here that researchers discovered Booster, a chimeric gene formed from multiple genetic fragments combined into one.

Where Did the Booster Gene Come From?

Booster evolved as a combination of three originally separate genetic sequences: one from a bacterium in the tree's root area; another from an ant associated with a fungus that infects the tree; and a third from the large subunit of a protein called RuBisCO (Ribulose-1,5-bisphosphate carboxylase-oxygenase).

Photosynthesis is the vital process by which plants convert sunlight into chemical energy. Improving this function not only implies greater growth but also more efficient use of resources like water and nutrients - something particularly relevant for cannabis, which requires careful environmental management.

Chloroplasts are the main cellular structures housing the photosynthetic apparatus that converts light energy into chemical energy to fuel plant growth. Specifically, the RuBisCO protein captures carbon dioxide from the atmosphere.

For years, scientists have been exploring ways to increase the amount of RuBisCO in plants to achieve higher yields and greater absorption of atmospheric CO2. When the team encouraged poplars to express the Booster gene more strongly, the results were astonishing.

The trees displayed up to 62% more RuBisCO content; around 25% increase in net CO2 uptake by leaves; up to 37% more growth in field trials; an 88% increase in stem volume; and, under controlled greenhouse conditions, up to a 200% increase in height.

Testing the same gene in Arabidopsis, a small flowering plant, increased its biomass and improved its seed production by 50%. Arabidopsis thaliana is the world's most studied plant at a genetic and physiological level. Its global distribution and adaptation to various habitats provide intriguing genetic variability in its wild populations. Leveraging this variability could be crucial for understanding processes related to stress tolerance.

Moreover, preserved chimeric genes like Booster are often dismissed as non-functional evolutionary artifacts that no longer influence plant processes. However, this study demonstrated the opposite: molecular and physiological validation confirmed that Booster enhances photosynthesis, allowing plants to perform better under constant and fluctuating light conditions.

In this July 2024 photo, ORNL's Biruk Feyissa, left, holds a five-month-old poplar tree expressing high levels of the Booster gene, while his colleague Wellington Muchero holds a tree of the same age with lower expression of the gene. Credit: Genevieve Martin/ORNL, U.S. Dept. of Energy.

Why Does This Matter?

Both black poplars and Arabidopsis belong to a group known as C3 plants, which includes major food crops like soybeans, rice, wheat, and oats. If Booster functions similarly in these plants, farmers could achieve higher yields without the need for additional land, water, or fertilisers.

Scientists are now exploring the possibility of testing these findings in different locations over extended periods. By trialling the Booster gene in various environments, they aim to determine its long-term performance and results.

This discovery opens a new avenue of scientific thought. We tend to view photosynthesis as a difficult process to improve. Yet, the molecular machinery surrounding photosynthesis has continued to evolve as plants adapt to their environments. In this case, DNA exchange with associated organisms fundamentally altered a biological process.

There is growing interest in determining whether similar results can be achieved for other crops which are important to the economy and to energy production. If efforts continue and produce consistent success, Booster could offer a straightforward way to enhance plant growth. More productive plants that use resources efficiently would help meet the world's increasing demand for food without overburdening existing farmland - and that would literally change everything.

Potential Applications in Cannabis Cultivation

Although the study focused on poplars, the implications of the Booster gene discovery could be extrapolated to cannabis and industrial hemp. These plants share many metabolic and physiological similarities with poplars, particularly regarding light capture and growth efficiency.

In cannabis cultivation, plant height and vigour are key factors for both biomass production in hemp and flower yields in varieties intended for recreational or medicinal use. If the Booster gene could be implemented in cannabis, it might result in more robust plants, higher yields, and reduced dependence on optimal environmental conditions.

Moreover, the ability of hemp to capture significant amounts of atmospheric carbon already positions it as an environmentally friendly crop. Introducing the Booster gene could enhance this capacity, making it a critical resource for combating climate change.

For cannabis destined for medicinal or recreational use, optimising photosynthesis could directly impact the production of cannabinoids and terpenes. By maximising metabolic efficiency, plants could generate higher concentrations of these compounds, improving the quality and value of the final product.

Challenges of Implementation

While the potential benefits are enormous, there are also significant challenges. Applying the Booster gene to cannabis would require extensive research to ensure its compatibility with the plant's specific characteristics. Additionally, the development of genetically modified strains could face regulatory hurdles in many countries with strict GMO laws.

Another factor to consider is market acceptance. Many cannabis users, particularly those seeking organic or natural products, might be reluctant to purchase items derived from genetically modified plants. Therefore, accompanying these developments with educational campaigns explaining the benefits and drawbacks of these innovations would be essential.

What is clear is that in a world where food demand continues to grow, breakthroughs like the Booster gene could be key to meeting consumer needs and addressing future challenges. Optimising resources will be crucial for humanity to overcome the climate change challenges we face.