79
Miscanthus Production
Some groups have attempted to improve performance by making triploid
or tetraploid hybrids of the two above-mentioned species, or by development
of selections from either of the parental species for desirable traits. The parental species have relatively wide distributions within East Asia and one can
find a wide range of phenotypes with different winter hardiness, daylength
sensitivity of flowering, and other important characteristics. Kalinina et al.
(2017) reported in detail a program to test multiple germplasms, plus some
new crosses, with M. × giganteus for a reference at multiple sites over a wide
range of climatic conditions. Results varied greatly over both years of study,
and sites, across Europe from Wales to Russia and Turkey. One triploid
hybrid M. × giganteus, “Nagara” bred in Europe by M. Deuter, has been used
to some extent in North America but its expected winter hardiness, observed
in Urbana, IL (Dong et al., 2019), has not proved out in practice in Ontario,
Canada (Sage et al., 2015).
There are several major practical challenges with managing Miscanthus
hybrids. One is concern for potential invasiveness of new fertile lines. Selfincompatibility may reduce problems with a single clone, but it is a hazard
of seed-grown hybrids. Both of the parental species of M. × giganteus are
classified as invasive in some states within the US. That does not mean that
they are prohibited, but it reduces their acceptability for widespread distribution and growth, because they may become seriously invasive under some
climatic conditions.
Further, in the US there are not mandates for use of carbon neutral strategies unlike in Europe (Clifton‐Brown et al., 2017) so that the biofuels market is not good. Ethanol from maize grain is the largest such biofuel and
cellulosic, derived from fermentation of cellulose, are unable to compete
economically. There is a small market for the direct use of M. × giganteus
as fuel, animal bedding, or dietary fiber, but that is satisfied by already
available M. × giganteus materials (Moberly Monitor, 2017; UIFM, 2020). The
situation is quite different in Europe, so that some large breeding programs
continue there.
An excellent review of the longest continuous breeding program, based
in Wales, is described by Clifton-Brown et al. (2019). Four tracks of breeding strategy were used to make most rapid progress with a perennial crop,
with a goal of identifying a seed-based production plan, rather than clonal
propagation as used with M. × giganteus. High yield, cold tolerance, drought
tolerance, climatic adaptability over a wide geographic area were among the
many characteristics being searched for in progeny of thousands of possible
crosses from a starting point of 240 genotypes.
A large practical concern in breeding and selection is for propagation
and establishment from seed (Xue et al., 2015). Miscanthus seeds are quite
small and the plantlets do not become competitive with agricultural weeds
until after at least a season’s growth. They are also very sensitive to drought