A clone of the hybrid perennial C4 grass Miscanthus ×giganteus (Mxg) is known for achieving exceptionally high rates of leaf CO2 uptake during chilling. Głowacka et al. study accessions from Japanese populations of M. sacchariflorus, M. sinensis and M. tinctorius whose leaves survived a natural late frost in the field and screen them for high maximum photosystem II efficiency following chilling weather. They find relatives of Mxg with significantly superior capacity for photosynthesis at chilling temperatures, apparently for the first time. As well as identifying important material for breeding new synthetic M. ×giganteus with a greater capacity for photosynthesis under chilling conditions, the results add further proof to the thesis that C4 photosynthesis is not inherently limited to warm climates.
