Cold Acclimation in Miscanthus.

Interest in the cultivation of biomass crops including Miscanthus × giganteus is increasing as global demand for biofuel grows. Miscanthus is a tall perennial grass species native to parts of Asia. It is now considered as a potential biofuel crop because of its relatively high dry matter yields across a range of environmental and soil conditions. The Miscanthus cultivar most commonly recommended for biofuel production is a sterile hybrid (M. × giganteus) of  M. sacchariflorus × M. sinensis, but there are some challenges for its production. One of them is the occurrence of cold damage during the first winter after planting when plant losses can be high. These losses could be exacerbated by incomplete or late senescence. Functionally, leaf senescence is not only a degenerative process, but also a recycling process when nutrients are translocated from the senescing cells to the storage organs (rhizomes in M. × giganteus).  A field trial was established in spring 2010 with split-plot randomized complete block design with 4 replications to evaluate the winter survival of nine different cultivars of Miscanthus. Plant growth characteristics and rhizome carbohydrate contents will be measured to determine how these factors contribute for winter survival of these lines. This study will answer the following questions:  

1) Does the rate of senescence influence winter survival?

2) Is there a predictive relationship between plant morphology and winter survival of Miscanthus ?

By spring 2011 all the lines have a 100 % survival rate. However results of this study revealed significant differences in biomass yield and plant morphology among these lines. Photosynthetic rates were also significantly different in all genotypes and significant changes in photosynthetic rates were also observed with change in environmental temperature throughout the season.