ree Fiber Level Drives Resilience and Hybrid Vigor in Energy Cane

Humanity is facing a pressing need to decarbonize the atmosphere in order to avoid catastrophic consequences. Sugar cane holds great potential to move towards a sustainable bioenergy production, as it is one of the most efficient biomass producing plants. However, the stagnant worldwide sugarcane yield is a menace to the fulfillment of its prospected contribution. Although promises abound of reaching that goal with new productive cultivars, there is a bottleneck not yet acknowledged: a dependable resilience of the cultivars. Resilience is a key factor in any agricultural crop and the genetic constitution of conventional sugarcane clearly shows why it fails in it. In a century-old sugarcane breeding system, one drive has prevailed: despite the cultivars having high concentration of sugar, they must consist of low fiber (12 ±2%), as allegedly the mills can operate with high efficiency. To accomplish this tradeoff, the sugary ancestral Saccharum officinarum contributes with nearly 85% to the genome of the cultivars, while the fibrous and resilient ancestral S. spontaneum complements the rest. With this composition, it has met the feedstock quality imposed by the industry, but the level of resilience is prejudiced. As result, the productivity of sugarcane has levelled off worldwide and the only chance of a leap forward is to break this captive dogmatism with energy cane: a plant with a higher contribution of the genome of S. spontaneum. With this gene influx, the resultant plant has higher resilience; the higher the genome contribution of this ancestral, the higher its resilience. This new hybrid type with high fiber content can definitively upgrade the biomass agroindustry, due to both its higher resilience and heterosis for biomass productivity and other favorable characteristics, thus giving a valuable contribution to CO2 mitigation.