2. Varieties Evaluated in Europe

Most European trials have involved clones of M. x giganteus, a triploid hybrid (n = 57) of uncertain origin, probably M. sinensis (diploid) x M. sacchariflorus (tetrapoloid). This was introduced into Denmark in 1935 from Yokohama, Japan, although the genus is known to occur throughout tropical, subtropical, and warm temperate parts of South-East Asia (where it probably has its origin) and the Pacific Islands. A member of the Andropogoneae/Poaceae family, the genus is closely related to Saccharum (which includes sugar cane), and some species of the two genera are easily intercrossed. In general, M. sacchariflorus types are well adapted for warmer climates, whereas M. sinensis can provide genetic resources for cooler regions. The European Miscanthus Improvement (EMI) project aims to broaden the genetic base of miscanthus, maximizing the productivity and adaptive range of the crop, and to develop methods for achieving these objectives. In 1997, extensive trials began of 15 genotypes across 5 different locations in Europe, from Sweden to Portugal (Lewandowski 1998a). Results to date from widespread trials suggest that yields of up to 25 t/ha/year (dry weight) may be obtained at the time of harvest (typically February), under conditions from central Germany (lat. 50 N) to southern Italy (lat. 37 N). More southerly locations, where water is usually a limiting factor in crop production, have employed irrigation. Yields in more northern parts of Europe (lat. above 50 N, generally without irrigation) are more typically 15 t/ha/year. The nitrogen requirement of miscanthus appears to be low, with no further response to fertilizer above about 150 kg N/ha/year.