Field Performance of Saccharum × Miscanthus Intergeneric Hybrids (Miscanes) Under Cool Climatic Conditions of Northern Japan

Physiological susceptibility to early- and late-season chilling limits commercial production of sugarcane (Saccharum spp. hybrid), a major crop for lignocellulosic biomass, refined sugar, and bioethanol, to tropical and the warmest subtropical regions. Interspecific and intergeneric hybridization have been used to broaden the genetic base of sugarcane and improve its adaptation to temperate climates. Chilling tolerance can be introgressed in sugarcane through intergeneric hybridization with Miscanthus, a cold-tolerant C₄ perennial grass, which is genetically homologous to sugarcane. This study evaluated intergeneric F₁ hybrids of Saccharum × Miscanthus, miscanes, which included two genotypes of sugarcane × Miscanthus sinensis and sixteen genotypes of sugarcane × Miscanthus sacchariflorus, for their seasonal variation in photosynthesis and biomass production under field conditions in Hokkaido, Japan, to identify promising genotypes and traits, which can be selected to further improve sugarcane. Results showed several of the miscane genotypes had high early- and late-season photosynthesis coupled with high biomass production, which likely indicates chilling tolerance. High broad-sense heritabilities for traits, including stem diameter, tiller number, leaf width, leaf and stem dry weight, and high correlations between these traits and dry matter yield indicate selections can be made efficiently to improve sugarcane. Although none of the miscanes overwintered at the experimental location, we identified miscane “JM 14-09” as a superior genotype for introgression breeding programs and as a potential energycane cultivar for its high biomass-production capacity.