A review of frost and chilling stress in Miscanthus and its importance to biomass yield

Abstract

Miscanthus is a perennial grass used as a low input biomass crop. Yield limitations are caused mainly by abiotic stresses such as cold, drought, and salinity. This review summarizes the current knowledge of the cold tolerance of miscanthus. Miscanthus has a relatively high cold tolerance compared to related C4 crops such as maize, sorghum, or sugarcane. M. × giganteus, the most commonly planted clone, has a high chilling tolerance compared to most other miscanthus genotypes tested thus far. A small number of recently reported genotypes with an even higher cold tolerance allow for further breeding improvements. The high rates of photosynthesis at low temperatures of M. × giganteus are not an effect of special protective mechanisms but rather of increased production of photosynthetic enzymes. M. × giganteus is relatively susceptible to frost damage in its rhizomes as well as its aboveground parts. Developing improved miscanthus varieties with increased cold tolerance could result in earlier canopy formation and a longer growing season resulting in larger biomass accumulation over the year and higher yields. Increased cold tolerance would allow to expand the miscanthus growing area and to reduce the risk of winter mortality.