As climate change ushers in hotter and drier growing seasons globally, researchers from the University of Nevada, Reno, have discovered promising varieties of cactus pear that may revolutionize biomass production for biofuels. Led by Professor John Cushman of the University’s Department of Biochemistry & Molecular Biology, the team identified several resilient and water-efficient cactus pear varieties suitable for fuel production.
The research, detailed in the Journal of Agronomy and Crop Science, is based on a three-year field trial conducted at the National Arid Land Plant Genetics Resources Unit near Fresno, California. The study assessed 14 cactus pear varieties under semi-arid conditions, revealing significant differences in biomass production. The top-performing variety outproduced the lowest by a factor of eight, showcasing notable variations in vegetative propagation and biomass yield.
A standout hybrid, a cross between a wild prickly pear native to Texas and a spineless variety developed by Texas A&M University’s Peter Felker, consistently delivered the highest biomass and cladode (the flattened stem of a cactus that functions as a leaf) production. This hybrid also demonstrated superior survival rates and ease of propagation, which could reduce labor costs associated with plant replacement.
The research reinforces earlier findings that cactus pear is highly efficient in water use, requiring significantly less water than traditional crops to produce comparable biomass. This characteristic is crucial as water resources become increasingly scarce, particularly in the western United States. Cushman highlighted the importance of exploring water-efficient crops to meet food, feed, and bioenergy needs under current climate conditions.
Cactus pear employs a metabolism with a unique photosynthesis method that enables survival in hot, arid climates. This process involves opening pores for carbon dioxide intake during cooler evening hours, thereby conserving moisture during the day.
Despite the promising results, further research is needed to address challenges such as diseases that stunt cactus growth and threats from the cochineal scale insect. Lead author Dhurba Neupane, now a research agronomist at the North Central Agricultural Research Laboratory, noted that cactus pear can be combined with agricultural waste to produce eco-friendly biofuels, highlighting its potential in sustainable energy production.
The next steps in the research include optimizing fertilization levels and planting densities to enhance biomass yield without overfertilization. Additionally, scientists aim to understand the adaptability of cactus pear across various regions in the American South and Southwest. Cushman emphasized the need for climate-resilient crops to ensure future food, forage, and biofuel supplies for a growing global population, positioning cactus pear as a critical and versatile crop deserving greater attention.
