Creation of novel tetraploid Miscanthus sinensis genotypes

Abstract

Miscanthus is emerging as one of the most promising lignocellulosic biomass crops for temperate climates due to its efficient C4 photosynthesis, resulting in high biomass accumulation, and its relative cold hardiness. Cultivation in Europe is dominated by one genotype, the sterile triploid hybrid M. × giganteus. One of its parent species, the mostly diploid Miscanthus sinensis, is also a valuable candidate as a biomass crop. Chromosome doubling can lead to gigantism, and also form the basis for new genomic combinations, creating × giganteus type hybrid plants from novel genetic backgrounds. For callus induction, 19 late flowering genotypes of M. sinensis and one genotype of M. sacchariflorus were used. 12 genotypes from this selection produced multiplying calli which were treated with 313 µM colchicine. Five genotypes regenerated shoots, and tetraploid plants were recovered from all. The regeneration of calli and the ability to form shoots were genotype dependent and was not influenced by application of different cytokinin regimes. Between 18 % and 100 % of plants regenerated after colchicine treatment were tetraploid. The resulting tetraploid plants will be examined in future field trails and enter crossing programs for the generation of novel hybrids.