High-parent heterosis for biomass yield in photoperiod-sensitive sorghum hybrids

• Measurement of high-parent heterosis in biomass sorghum hybrids.
• Both the hybrids and high-parent pollinators were photoperiod sensitive.
• Across environments, the average high-parent heterosis of the hybrids was 24.8%.
• Hybrid biomass yields were 5.4 Mg/ha higher than the high-parent pollinators.

Biomass sorghums are being developed as a dedicated energy crop. These sorghums are managed to maximize biomass yields and are tall (3.5–5 m) with dry, pithy stems. To facilitate seed production, they are produced as hybrids using grain sorghum seed parents. Besides facilitating seed production, these hybrids may provide high-parent heterosis for improved biomass yields. To measure potential heterosis, biomass hybrids derived from 13 different biomass pollinators and 4 grain sorghum seed parents were evaluated for biomass yield in 4 environments. High-parent heterosis in these hybrids averaged 24.8% across all the environments and was available in many hybrid combinations. Hybrids out-yielded the pollinators in each environment. Across environments, the hybrids yielded 32.4 Mg/ha compared to the 27.0 Mg/ha of the pollinators. While heterosis was available in many hybrids, specific combining abilities and environmental interactions combine to maximize heterosis and biomass yields. Heterosis can serve as an effective tool for improving biomass sorghum yields.