ArticlePDF Available

Performance of 15 Miscanthus Genotypes at Five Sites in Europe

Authors:

Abstract and Figures

to have exceptionally vigorous growth (Linde-Laursen, 1993). In the late 1980s, interest in C4 perennial rhizoma- Miscanthus is a genus of high-yielding perennial rhizomatous tous grasses, such as Miscanthus spp. (Nielsen, 1987), grasses with C4 photosynthesis. Extensive field trials of Miscanthus spp. biomass production in Europe during the past decade have shown switchgrass (Panicum virgatum L.) (Christian, 1994), several limitations of the most widely planted clone, M. giganteus Cyperus spp., and Spartina spp. (Potter et al., 1995), for Greef et Deu. A 3-yr study was conducted at five sites in Europe biofuel production increased due to their high yield (Sweden, Denmark, England, Germany, and Portugal) to evaluate potential and rising energy prices. Since 1983, extensive adaptation and biomass production potential of four acquisitions of field trials of M. giganteus have been carried out in M. giganteus (No. 1-4) and 11 other genotypes, including M. sac- northern Europe, showing the capacity of this genotype chariflorus (Maxim.) Benth. (No. 5), M. sinensis Andersson (No. for yields 20 t dry matter ha
Content may be subject to copyright.
CLIFTON-BROWN ET AL.: PERFORMANCE OF MISCANTHUS GENOTYPES IN EUROPE 1013
feed composition. 3rd rev. National Academy Press, Washing- Traxler, M.J., D.G. Fox, P.J. Van Soest, A.N. Pell, C.E. Lascano,
D.P.D. Lanna, J.E. Moore, R.P. Lana, M. Ve
´lez, and A. Flores.ton, DC.
Robertson, J.B., and P.J. Van Soest. 1981. The detergent system of 1998. Predicting forage indigestible NDF from lignin concentration.
J. Anim. Sci. 76:1469–1480.analysis and its application to human food. p. 123–158. In W.P.T.
James and O. Theander (ed.) The analysis of dietary fiber in foods. Van Soest, P.J. 1994. Nutritional ecology of the ruminant. 2nd ed.
Cornell Univ. Press, Ithaca, NY.Marcel Dekker, New York.
Rodrı
´guez, C.A., J. Gonza
´lez, M.R. Alvir, and C. Cajarville. 1999. Van Soest, P.J., J.B. Robertson, and B.A. Lewis. 1991. Methods for
dietary fiber, neutral detergent fiber, and nonstarch polysaccha-Underestimation of in situ effective degradability of N due to
microbial contamination. p. 67. In G.E. Lobley et al. (ed.) 8th rides in relation to animal nutrition. J. Dairy Sci. 74:3583–3597.
White, B.A., R.J. Mackie, and K.C.Doerner.1993.Enzymatichydroly-Int. Symp. on Prot. Met. and Nutr., Aberdeen. 1–4 Sept. 1999.
Wageningen Pers., the Netherlands. sis of forage cell walls. p. 465–484. In H.G. Jung et al. (ed.) Forage
cell wall structure and digestibility. ASA, CSSA, and SSSA, Madi-Sniffen, C.J., J.D. O’Connor, P.J. Van Soest, D.G. Fox, and J.B.
Russell. 1992. A net carbohydrate and protein system for evaluating son, WI.
Yemm, E.W., and A.U. Willis. 1954. The estimation of carbohydratescattle diets: II Carbohydrate and protein availability. J. Anim.
Sci. 70:3562–3577. in plant extracts by anthrone. Biochem. J. 57:508–514.
Performance of 15 Miscanthus Genotypes at Five Sites in Europe
John C. Clifton-Brown,* Iris Lewandowski, Bengt Andersson, Gottlieb Basch, Dudley G. Christian,
Jens Bonderup Kjeldsen, Uffe Jørgensen, Jørgen V. Mortensen, Andrew B. Riche,
Kai-Uwe Schwarz, Koeyumars Tayebi, and Fernando Teixeira
ABSTRACT to have exceptionally vigorous growth (Linde-Laursen,
1993). In the late 1980s, interest in C
4
perennial rhizoma-
Miscanthus is a genus of high-yielding perennial rhizomatous tous grasses, such as Miscanthus spp. (Nielsen, 1987),
grasses with C
4
photosynthesis. Extensive field trials of Miscanthus
spp. biomass production in Europe during the past decade have shown switchgrass (Panicum virgatum L.) (Christian, 1994),
several limitations of the most widely planted clone, M. giganteus Cyperus spp., and Spartina spp. (Potter et al., 1995), for
Greef et Deu. A 3-yr study was conducted at five sites in Europe biofuel production increased due to their high yield
(Sweden, Denmark, England, Germany, and Portugal) to evaluate potential and rising energy prices. Since 1983, extensive
adaptation and biomass production potential of four acquisitions of field trials of M. giganteus have been carried out in
M. giganteus (No. 1–4) and 11 other genotypes, including M. sac- northern Europe, showing the capacity of this genotype
chariflorus (Maxim.) Benth. (No. 5), M. sinensis Andersson (No. for yields 20 t dry matter ha
1
year
1
(Nielsen, 1987;
11–15), and hybrids (No. 6–10). At each site, three randomized blocks Schwarz et al., 1994).
containing a 5- by 5-m plot of each genotype were established (except There are several reasons why European-wide bio-
in Portugal where there were two blocks) with micropropagated plants
at 2 plants m
2
. In Sweden and Denmark, only M. sinensis and its mass production from a single genotype within the Mis-
hybrids satisfactorily survived the first winter following planting. Mean canthus genus is inadequate. First, in northern Europe,
annual yields across all sites for all surviving genotypes increased each a number of sites established with M. giganteus failed
year from 2 t ha
1
dry matter following the first year of growth to 9 to survive during the first winter (Jones and Walsh,
and 18 t ha
1
following the second and third year, respectively. Highest 2001), principally due to insufficient freeze tolerance of
autumn yields at sites in Sweden, Denmark, England, and Germany the overwintering rhizome. Second, it is unlikely that
were 24.7 (M. sinensis hybrid no. 8), 18.2 (M. sinensis hybrid no. 10), one single clone is sufficient to fulfil all of the quality
18.7 (M. giganteus no. 3), and 29.1 t ha
1
(M. giganteus no. 4), requirements of different uses (combustion and fiber).
respectively. In Portugal, where irrigation was used, the top-yielding Third, M. giganteus, being a sterile triploid (Greef
genotype produced 40.9 t ha
1
dry matter (M. sinensis hybrid no. 7).
Highest-yielding genotypes in Sweden and Denmark were among and Deuter, 1993), must be propagated vegetatively,
the lowest yielding in Portugal and Germany, demonstrating strong either with rhizome cuttings or by micropropagation,
genotype environment interactions. making establishment expensive compared with crops
established from seed. Fourth, growing large areas of a
single clone increases disease risk. A broad genetic base
MISCANTHUS giganteus was introduced to Europe and the provision of different Miscanthus genotypes are
in the 1930s by Aksel Olsen and was observed required to overcome these limitations.
As part of the European Miscanthus Improvement
J.C. Clifton-Brown and I. Lewandowski, Univ. of Hohenheim, Inst. Project, a Miscanthus gene pool was created by combin-
for Crop Prod. and Grassl. Res. (340), D-70599 Stuttgart, Germany; ing collections directly from Asia and material already
B. Andersson, Svalo
¨f Weibull, AB-S 268 81, Sweden; G. Basch, K. made available in Europe by German, Danish, and Swed-
Tayebi, and F. Teixeira, Departamento de Fitotecnica, Universidade ish breeders. M. sinensis is characterized by a tuft-form-
de E
´vora, Herdade da Mitra, P-7001 Evora/Codex, Portugal; D.G.
Christian and A.B. Riche, Rothamsted Exp. Stn., Harpenden, Hert- ing rhizome with high shoot densities while M. sacchari-
fordshire AL5 2JQ, United Kingdom; and J. Bonderup Kjeldsen, U. florus is characterized by a broad, creeping rhizome
Jørgensen, J.V. Mortensen, and K.-U. Schwarz, Danish Inst. of Agric. with thick tall stems. M. giganteus shows an intermedi-
Sci., Dep. of Soil Sci., Res. Cent. Foulum, P.O. Box 50, 8830 Tjele, ate type of rhizome between M. sinensis and M. sacchari-
Denmark. Current address of J.C. Clifton-Brown: Bot. Dep., Univ.
of Dublin, Trinity College, Dublin 2, Ireland. This work was funded florus and is most probably a natural hybrid of the two
by the EU Contract no. FAIR3 CT-96-1392. Received 6 Oct. 2000. (Greef and Deuter, 1993; Hodkinson et al., 1997).
*Corresponding author (jcbrown@tcd.ie). In this paper, we report on field trials planted with
15 Miscanthus genotypes, which can be broadly divided
Published in Agron. J. 93:1013–1019 (2001).
1014 AGRONOMY JOURNAL, VOL. 93, SEPTEMBER–OCTOBER 2001
Table 1. Miscanthus genotypes used in field trials, showing the European Miscanthus Improvement project (EMI) number, genotype
name, genotype group abbreviation, ploidy, and acquisition details.
EMI no. Name Group Ploidy Acquisition code Acquired from Additional Information
1M. giganteus Gig 3n LASEI1 Larsen, Denmark No. 16.05 in Greef et al., 1997
2M. giganteus Gig 3n ILP53 Knoblauch, Hornum No. 16.21 in Greef et al., 1997
3M. giganteus Gig 3n HAGA 56 Hagemann, Berlin No. 17.02 in Greef et al., 1997
4M. giganteus Gig 3n GREIF63 Greifswald Bot. Gnd. No. 17.03 in Greef et al., 1997
5M. sacchariflorus Sac 4n MATEREC11 Deuter, Germany Matumura et al., 1985
6M. sinensis Hybrid Sin-H 3n GOFAL7 Deuter, Germany Hybrid selected in a M. sinensis population
7M. sinensis Hybrid Sin-H 2n BERBO42 Deuter, Germany Hybrid of two M. sinensis
8M. sinensis Hybrid Sin-H aneuploid RH43 Deuter, Germany Hybrid of M. sacchariflorus M. sinensis
9M. sinensis Hybrid Sin-H 2n JESEL78 Deuter, Germany Hybrid of two M. sinensis
10 M. sinensis Hybrid Sin-H 2n RH81 Deuter, Germany Hybrid of M. sacchariflorus M. sinensis
11 M. sinensis Sin 2n 88-110 Brander, Denmark Collected in Honshu, Japan in 1983, selected 1988
12 M. sinensis Sin 2n 88-111 Brander, Denmark Collected in Honshu, Japan in 1983, selected 1988
13 M. sinensis Sin 2n 90-5 Brander, Denmark Collected in Honshu, Japan in 1983, selected 1990
14 M. sinensis Sin 2n 90-6 Brander, Denmark Collected in Honshu, Japan in 1983, selected 1990
15 M. sinensis Sin 2n SW217 Andersson, Sweden Collected Hokkaido, Japan in 1990
into four genetic groups, at five locations: Sweden, Den- Field Trials
mark, England, Germany, and Portugal. The objective To ensure genetic and physiological uniformity at the five
was to screen these genotypes in different soil and cli- sites in Sweden, Denmark, England, Germany, and Portugal,
matic conditions for yield performance traits, including all 15 genotypes were micropropagated by explants. Genotype
height, stem density, flowering time, autumn senescence no. 1–10 were propagated by Martin Deuter at TINPLANT
rate, and yield. These measurements were used to iden- (Klein-Wanzleben, Germany), and Genotype no. 11–15 were
propagated at the Danish Institute of Plant and Soil Science
tify the most suitable genotypes for the various regions
(Aarslev, Denmark). After in vitro multiplication, the plants
of Europe and to improve our knowledge of the genetic were grown for 8 to 10 wk in a temperate greenhouse in 5-
base for the future development of Miscanthus spp. as by 5-cm peat pots before shipping to the field trials. Plant
a biomass crop. height at planting averaged 20 cm.
At each site, three randomized blocks containing a 5- by
5-m plot of each genotype were established (except in Portugal
MATERIALS AND METHODS
where there were two blocks). Plantlets were planted by hand
Genotypes between March and June 1997 at a density of 2 plants m
2
.
Plots were irrigated after planting at all sites. In Portugal,
From the gene pool held by European breeders, 15 of the
irrigation was necessary throughout all growing seasons be-
most promising genotypes were selected (Table 1). Four acqui-
cause of the limited rainfall during the growing season and
sitions of M. giganteus genotypes (No. 1–4) were chosen
sandy soils (Tables 2 and 3). Fertilizer was applied at rates
because different crosses between M. sacchariflorus and M.
equivalent to 60, 44, and 110 kg ha
1
yr
1
N, P, K, respectively,
sinensis were suspected to be in circulation all under the same
which, combined with residual nutrients, was estimated to
name. Amplified fragment length polymorphism (AFLP) analy-
sis had revealed small detectable differences between some saturate crop requirements (Lewandowski et al., 2000). Me-
chanical weed control was used between transplanting andof these acquisitions (Greef et al., 1997). One, M. sacchari-
florus (No. 5), was selected from a collection described by September in 1997.
Plant survival during the first winter was quantified byMatumura et al. (1985). Five pure M. sinensis types were
selected, four of which were collected by the Danish collector counting the number of plants producing new shoots in spring
1998, and percentages of the total plants planted in 1997 werePoul Brander in 1983 on Honshu Island (No. 11–14) and one
from central Hokkaido in 1990 by the Swedish collector Zan- calculated. Five plants were tagged for regular measurements
at the beginning of each growing season on plants in predeter-dra Andersson (No. 15). Five Miscanthus spp. hybrids from
crosses within M. sinensis and M. sacchariflorus (No. 6–10) mined positions at least two rows from the edge of each plot.
Tagged plants were in the middle of the plots to avoid borderwere selected based on known differences in key physiological
characteristics such as flowering time and autumn senes- effects. Stem density and canopy height were monitored regu-
larly within the growing season on the tagged plants. In eachcence time.
Table 2. Site locations, planting dates in 1997, soil textures (sand, silt, and clay), soil bulk densities (bulk), and soil types to subgroup
level in five countries.
Soil characteristics (0–90 cm)
Country Location Planting date Sand Silt Clay Bulk Soil type†
%gcm
3
Sweden 5560N, 1400E 17 June 83.0 12.0 5.1 1.5 Aeric Endoaquept
Denmark 5630N, 0935E 03 June 63.1 25.8 11.2 1.5 Typic Fragiudalf
England 5148N, 0021W 22 May 41.5 29.2 29.4 1.7 Aquic Paleudalf
Germany 4840N, 0900E 21 May 8.2 51.7 40.2 1.5 Vertic Eutrudept
Portugal 3843N, 0913W 21 Mar. 76.2 15.7 8.1 1.6 Aquic Xerofluvent
† Soil Survey Staff, 1999.
CLIFTON-BROWN ET AL.: PERFORMANCE OF MISCANTHUS GENOTYPES IN EUROPE 1015
Table 3. Mean air temperature and rainfall at the field sites in the five countries for the period April to September in 1997, 1998, and
1999; the long term (LT) mean for this period (10 yr data during last 30 yr), and the annual LT (Ann.) mean.
Air temperature Rainfall
April to September April to September
Ann. LT Ann. LT
Country 1997 1998 1999 LT mean mean 1997 1998 1999 LT mean mean
Cmm
Sweden 13.4 12.5 13.8 13.0 7.9 297 459 416 359 696
Denmark 12.9 12.0 13.0 12.1 7.3 354 334 409 334 626
England 14.2 13.6 14.4 12.9 9.1 273 436 364 319 688
Germany 13.6 13.8 14.9 13.3 7.9 374 326 410 425 687
Portugal† 23.0 21.4 20.2 19.6 15.4 327 197 147 156 665
† In Portugal, irrigation between April and September was 300, 382, and 506 mm in 1997, 1998, and 1999, respectively.
autumn, greenness (an indication of the senescence) of the RESULTS AND DISCUSSION
shoots was assessed on the tallest shoot of three of the tagged Climatic Conditions during the Growing Season
plants. If the length of the green part of a fully expanded leaf
was 60%, then it was counted as green. If the green part Mean air temperatures and rainfall sums from April
was 60%, then it was counted as dead. Green leaf area was to September are given in Table 3 for all 3 yr of the
estimated by eye. Percentage greenness was calculated from field trials. The long-term means (10 yr of data) and
the sum of green-scored leaves over the total number of leaves the whole year are also shown. Growing season air tem-
on a shoot 100. Three shoots per plot were pooled to make peratures in 1997, 1998, and 1999 were generally warmer
a plot mean, and plot means were used as replicates (n3, than normal for the five locations. Air temperatures in
except Portugal where n2). Portugal were at least 5C higher than at the other lo-
Each autumn, a sample of 2 m
2
was harvested from within cations.
the central area of the plot (avoiding border effects) to assess
Long-term annual rainfall at all sites was similar (626–
the total aboveground productivity of each genotype. Cutting
height for yield determinations was 5 cm. Moisture content 696 mm), but rainfall distribution varied markedly with
was measured by drying at 80C until constant weight had location. On average, the German site had relatively
been achieved, and dry matter yield was calculated as tonnes wet summers (425 mm) while Portugal had wet winters
of dry matter per hectare. (509 mm). Consequently, in Portugal, natural water avail-
ability for crop growth was very limited, and irrigation
was necessary.
Statistical Analyses
When data were normally distributed, analysis of variance Plant Survival
(ANOVA) was used to determine significant differences. For
comparisons of shoot density, plant height, and yield among Established Miscanthus spp. stands grow from over-
genotypes within a country at a particular sampling time, a wintering rhizomes in spring. At the more northern sites
minimum significant difference was calculated by the Tukey of Denmark and Sweden, nearly 100% and 50% of
procedure at P0.05. Interactions among genotype, year, the plants of M. giganteus and M. sacchariflorus, re-
and country, where appropriate, are shown in the tables. For spectively, died during the first winter following plant-
shoot greenness, plot means from the five selected plants were ing, but losses of M. sinensis plants were only 1 to 16%
used from the three replicate plots for each genotype at each (Table 4). In Denmark and Sweden, plant losses of M.
site to produce a standard error. Regression relationships be- sinensis hybrids (No. 6–10) varied from only 1% in Ge-
tween genotype yields in the different years were calculated notype no. 10 to 60% in Genotype no. 9. In these coun-
across all countries. Plant height and shoot density in the third tries, winter soil temperatures in the first year following
growing season were regressed with yield to assess the yield planting fell below 4.5C. In England, Germany, and
predictability using these simple growth parameters. All statis- Portugal, where winter soil temperatures were warmer
tics were performed within Data Desk v.6 (Data Description,
Ithaca, NY). (⬎⫺2.8C), all genotypes survived. These observations
Table 4. Plant losses and minimum soil temperature recorded at 5-cm depth in the field during the first winter (1997–1998) for the 15
Miscanthus genotypes at five sites.
Genotype group and no.
Gig Sin-H Sin
Sac Soil
Country 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 temp.
% plant loss C
Sweden 99 93 97 99 50 17 52 6 50 2 6 5 16 5 5 5.4
Denmark 100 98 96 96 67 1 8 6 60 1 1 10 15 6 1 4.5
England 0 0 0 0 2 0 0 1 1 0 4 1 21 1 0 1.2
Germany 0 1 0 1 1 0 5 0 1 0 1 0 0 1 5 2.8
Portugal 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 NA
1016 AGRONOMY JOURNAL, VOL. 93, SEPTEMBER–OCTOBER 2001
Table 5. Autumn yield for the first 3 yr (1997, 1998, and 1999) of 15 Miscanthus genotypes grown at five locations in Europe.
Genotype group and no.
Gig Sin-H Sin
Sac Tukey‡
Country Year Date† 123456789101112131415MeanMSD
dry matter yield, t ha
1
Sweden 1997 12 Nov. 0.1 0.1 0.1 0.1 0.5 0.2 0.4 0.4 0.6 0.8 0.4 0.2 0.2 0.4 0.3 0.3 0.6
1998 24 Nov. 0.0 0.0 0.0 0.0 0.0 5.0 3.8 9.5 5.4 11.4 5.2 5.0 6.7 3.9 3.1 3.9 4.4
1999 18 Oct. 0.0 0.0 0.0 0.0 0.0 19.3 11.0 24.7 14.2 20.5 15.4 15.3 17.3 13.8 9.7 10.7 8.0
Denmark 1997 27 Nov. 0.7 0.8 1.1 0.8 0.5 0.9 1.1 0.3 1.4 1.4 0.4 0.3 0.3 0.6 0.2 0.7 0.7
1998 19 Nov. 0.0 0.0 0.0 0.0 0.7 5.2 4.7 4.1 1.4 7.8 5.2 3.1 3.3 2.4 1.9 2.7 3.0
1999 18 Nov. 0.0 0.0 0.0 0.0 1.4 16.4 10.4 15.9 0.9 18.2 15.0 12.4 11.2 9.9 6.8 7.9 5.1
England 1997 15 Nov. 0.6 0.8 0.9 0.8 0.4 1.4 1.2 0.2 1.7 0.8 0.1 0.1 0.2 0.1 0.2 0.6 0.8
1998 24 Nov. 3.0 5.7 5.9 5.3 1.9 7.0 5.9 1.4 7.7 6.0 1.9 2.0 3.0 0.6 2.0 4.0 3.8
1999 3 Nov. 13.8 16.8 18.7 14.6 11.1 15.7 17.7 6.5 15.8 14.0 8.0 7.0 10.9 4.6 5.9 12.1 7.4
Germany 1997 11 Nov. 3.2 3.4 3.3 3.0 2.9 2.8 1.1 1.0 3.0 1.9 0.7 0.6 1.0 0.5 0.5 1.9 2.0
1998 23 Nov. 8.0 8.7 8.9 8.1 4.6 7.4 3.6 7.3 7.6 9.7 4.4 4.5 5.0 3.6 2.5 6.2 5.2
1999 21 Nov. 22.8 24.3 25.7 29.1 12.6 20.0 17.0 19.2 10.3 19.1 12.8 10.9 12.3 10.4 9.1 17.0 15.3
Portugal 1997 27 Oct. 8.4 4.6 6.0 8.1 4.4 7.9 7.5 2.5 7.6 6.3 5.9 4.7 5.7 5.3 2.0 5.8 2.7
1998 15 Oct. 26.9 25.5 30.3 25.6 15.1 18.4 27.2 10.8 20.1 13.6 10.6 10.2 16.3 11.6 8.8 18.1 8.5
1999 6 Oct. 37.8 36.4 36.8 34.7 35.2 27.2 40.9 21.0 26.3 20.3 16.2 16.3 22.4 16.1 16.1 26.9 17.1
ANOVA All countries, genotypes, and years
Source of variation df P
Country 4 ***
Genotype 14 ***
Country genotype 56 ***
Year 2 ***
Country year 8 ***
Genotype year 28 ***
Country genotype year 92 ***
*** Significant at the 0.001 probability level. ANOVA’s on the three years within each site showed genotype, year, and genotype year differences were
all highly significant (***) (not shown above).
† Harvest date.
‡ Minimum significant differences (MSD) between genotypes within a site and within a year were calculated by the Tukey test at P0.05.
are consistent with artificial freezing tests, which showed outyielded all other genotypes in Sweden and Denmark
(11.4 and 7.8 t ha
1
, respectively). This indicates thatthat rhizomes of M. sinensis hybrids could survive tem-
peratures below 4.5C, but rhizomes of M. giganteus M. sinensis hybrid no. 10 is better suited to low winter
soil temperatures and shorter growing seasons thanand M. sacchariflorus are killed at approximately 3C
(Clifton-Brown and Lewandowski, 2000). It appears, other genotypes in these trials.
In the third year, the highest-yielding genotypes intherefore, that temperatures in Sweden and Denmark
were too cold for M. giganteus and M. sacchariflorus. Germany and England were of M. giganteus. In Portu-
gal, the highest yield was obtained from M. sinensisConsequently, M. sinensis and M. sinensis hybrids can
be recommended for the regions where soil tempera- hybrid no. 7, with autumn yield of 40.9 t ha
1
.M. sinensis
genotypes (No. 11–15) produced a consistently lowertures at 5-cm depth are likely to fall below 3C.
yield than the highest-yielding genotype at any given
location. Interestingly, at the higher latitudes in Sweden
Biomass Yield and Denmark, the yield gap between the M. sinensis
Following planting in 1997, average biomass yield for genotype group (No. 11–15) and the other genotypes
all genotypes across all sites was only 1.9 t ha
1
in au- was smaller than at lower latitudes. This can be ex-
tumn (Table 5). Highest mean yields were in Portugal plained through lower overall yields at higher latitudes
(5.8 t ha
1
) while lowest yields were in Sweden (0.36 t due to the shorter growing season.
ha
1
). There were several reasons for this. First, late Biomass yield interactions between year and geno-
frosts in Sweden prevented planting before June, thus type in any given country were significant at P0.001.
shortening the growing season by 2 mo compared with Interactions among country, year, and genotype were
Portugal. Second, the plants were irrigated in Portugal, also significant at P0.001. This shows that stand
but in Sweden, growth was probably water limited be- maturity increases yield significantly for all surviving
cause rainfall was abnormally low (Table 3). Third, genotypes. Equally, the different environmental condi-
growth temperatures in Portugal were higher through- tions, particularly climate and soil, influence genotype
out the season, promoting faster establishment. yield performance (Table 5).
In the second year, average yield for all sites and all Comparisons between yields obtained in these field
surviving genotypes increased to 8.6 t ha
1
. In Portugal, trials and other trials in Europe can only be made for
M. giganteus yields averaged 27 t ha
1
, but in England the widely grown M. giganteus. Trials in northern
and Germany, where average air temperatures were regions tend to mature slower than at southern latitudes,
approximately 5C lower and plants were not irrigated, and ceiling yields of 15 t ha
1
are reached after only the
fourth or fifth year (Lewandowski et al., 2000). Yieldsyields did not exceed 9 t ha
1
.M. sinensis hybrid no. 10
CLIFTON-BROWN ET AL.: PERFORMANCE OF MISCANTHUS GENOTYPES IN EUROPE 1017
Table 6. Correlations between yields in the first, second, and third
a photosynthetic group, radiation conversion efficiency
growing seasons and the shoot densities and plant height using
varies little (Monteith, 1978). Thus, yield from a given
data from all sites and all genotypes except for those that died
genotype will depend largely on the efficiency with which
in Sweden and Denmark during the first winter following
radiation is intercepted by the canopy leaves. This effi-
planting.
ciency is dependent on a range of characteristics, in-
Variable 1 Variable 2 df Slope PConstant Pb
2
cluding shoot emergence time from the overwinter-
Yield year 1 Yield year 3 64 2.9 *** 11.0 *** 0.56
ing rhizome and rate of canopy closure [a function of
Yield year 2 Yield year 3 64 1.2 *** 8.0 *** 0.81
shoot density and leaf expansion rate (Clifton-Brown
Yield year 3 Shoot density year 3 64 0.0 NS† 14.8 *** 0.07
Yield year 3 Height year 3 64 0.1 *** 4.5 NS 0.54
and Jones, 1997), flowering time after which growth stops
and senescence begins]. These characteristics are de-
*** Significant at the 0.001 probability level.
† NS, not significant at P0.05.
tailed here for the third year following planting.
Genotypic differences in shoot emergence time in
the spring were not observed within these field trials.
with irrigation in excess of 25 t ha
1
in southern Europe Evidently, monthly measurements of plant height were
are often achieved in the second year with M. gigan- insufficient to identify emergence differences at a site
teus (Clifton-Brown et al., 2001). Therefore, in warm (data not shown). However, the monthly measurements
climates, yields after the second growing season are a did show the earlier start to the growing season in Portu-
good indication of the potential ceiling yield from a gal (data not shown). By the end of the third growing
genotype, but in cooler climates, it takes at least 3 yr season, plants were tallest in Portugal (223 cm) and
to reach a ceiling. As expected, regression coefficients shortest in Denmark (120 cm) (Table 7).
with third-year yield against first- and second-year yields Analysis of variance showed that shoot density and
were better for the second year than for the first year plant height differed significantly for all 15 genotypes
(Table 6). within and between countries (P0.001) at the end of
the growing season (Table 7). In those countries where
Growing Season Performance Characteristics M. giganteus and M. sacchariflorus survived the first
winter, plants were generally taller than the M. sinensis
The greatest yield variance from site to site was ob- and M. sinensis hybrids. In contrast, shoot densities were
served in the M. sinensis hybrid genotypes. For example, higher in the M. sinensis and M. sinensis hybrids. Evi-
the lowest autumn yields in Sweden were for Genotype dently, there is an antagonistic relationship between
no. 7, the genotype that performed best in Portugal plant height and shoot density.
and England. For future breeding of higher yielding
Genotypic variation in plant height appears to be
Miscanthus genotypes better suited to specific environ-
associated with flowering time. The tallest genotypes at
ments, it will be necessary to identify key growth charac-
a site (e.g., M. sacchariflorus or M. giganteus ) tended
teristics that will increase the quantity of radiation inter-
to flower later than the earliest-flowering M. sinensis
cepted and its conversion into harvestable dry matter
genotypes (No. 11–15). Indeed, it was only in Portugal
over a growing season. Recent evidence suggests that
where all of the genotypes reached flowering before
photosynthetic efficiency per unit area of leaf has not
autumn (Table 8). Thermal time required from emer-
been successful in identifying more productive geno-
types of crop plants (Lawlor, 1995). Furthermore, within gence in spring to flowering of M. giganteus in Portu-
Table 7. Shoot density and plant height at the end of the growing season for 15 Miscanthus genotypes grown at five locations in Europe.
Genotype group and no.
Gig Sin-H Sin
Sac Tukey†
Country 123456789101112131415MeanMSD
Shoot density, m
2
Sweden 0000075551625513712713111910810071 36
Denmark 0000869511011014110796841157357 36
England 51 58 56 53 36 95 93 124 122 178 115 99 112 82 99 92 61
Germany 67 75 63 70 45 98 67 225 46 196 126 129 114 117 104 103 29
Portugal 88 82 75 95 82 165 113 270 133 273 252 196 168 226 284 167 57
Plant height, cm
Sweden 00000271142234185255217216233232220147 33
Denmark 0000184196165182112180167160172151136120 22
England 221 245 247 225 251 199 183 120 163 178 155 140 142 104 141 181 36
Germany 273 278 261 283 308 192 178 172 127 183 175 175 175 177 160 208 47
Portugal 295 300 305 301 383 169 287 148 198 145 159 167 168 162 156 223 27
ANOVA
Source of variation df Shoot Height
Country 4 *** ***
Genotype 14 *** ***
Country genotype 56 *** ***
*** Significant at the 0.001 probability level.
† Minimum Significant Differences (MSD) between genotypes within a site and within a year were calculated by the Tukey test at P0.05.
1018 AGRONOMY JOURNAL, VOL. 93, SEPTEMBER–OCTOBER 2001
Table 8. Flowering date and shoot greenness (%) in autumn at the end of the third growing season (1999) for 15 Miscanthus genotypes
grown at five locations in Europe.
Genotype group and no.
Gig Sin-H Sin
Sac
Country 123456789101112131415
Flowering date
Sweden †††††8Sept. none none 20 Sept. 8 Sept. 10 Aug. 10 Aug. 20 Aug. 2 Aug. 25 July
Denmark†††††15Sept. none 15 Oct. 15 Oct. 15 Sept. 20 Aug. 20 Aug. 25 Aug. 20 July 20 July
England none none none none none 29 Sept. none 29 Sept. 29 Sept. 29 Sept. 22 July 22 July 22 July 22 July 22 July
Germany none none none none none 26 Aug. 20 Sept. 20 Sept. 20 Sept. 12 Aug. 13 July 30 June 13 July 30 June 30 June
Portugal 10 Sept. 13 Sept. 10 Sept. 10 Sept. 16 Sept. 6 July 10 Aug. 6 July 19 July 22 June 8 June 8 June 15 June 4 June 4 June
Greenness (%)‡
Sweden †††††0463221515 2 200000
Denmark††††247843920601000000
England 25 16 0 16 11 0 24 405220722000000
Germany 17 32001532271531536220444210422210 0 0
Portugal 53 35124914524044426042465663734374824212 45 5482
† Indicates plants did not survive the first winter following planting.
‡ Means shown are 1SE,n3, except Portugal where n2.
gal was 1800 degree days above a threshold of 10C. 6) for the genotypes tested. Exceptions to these general
relationships included M. sacchariflorus (No. 5), whichIn contrast, the M. sinensis genotypes (No. 11–15) only
needed 400 to 600 degree days in Portugal. This effec- despite being the tallest genotype, had a low shoot den-
tively halves the length of the available growing season, sity that lowered its yields below the highest-yielding
approximately halving the yield (Tables 5 and 8). In genotypes (Table 7). M. sinensis hybrid genotypes (No.
Sweden and Denmark, where temperatures are lower, 6–10) showed the potential for breeding genotypes with
M. sinensis flowers later in the growing season so that appropriate characteristics for a wide range of environ-
less radiation is lost than at warmer sites. As with yield mental conditions. For future breeding, M. sacchari-
(Table 5), flowering time was most variable for the M. florus will be an invaluable parent to create new taller,
sinensis hybrid (No. 6–10) group within a site. For exam- and therefore, higher yielding M. sinensis hybrid geno-
ple, in Portugal, Genotype no. 7 was late flowering, and types with rhizome freezing tolerance and late flow-
this coincided with the highest yield recorded through- ering time.
out (Table 5).
In general, late flowering was associated with late Practical Issues in Relation to Miscanthus spp.
senescence. For example, Genotype no. 7 senesced lat- Production for Biomass
est at all sites and was still relatively green compared
Without irrigation, Miscanthus spp. would not be pro-
with all other genotypes except Genotype no. 9 in late
ductive in Portugal because of the combination of a
autumn (Table 8). Although early flowering leads to
low water-retentive sandy soil type, high evaporative
nearly complete senescence in northern climates, it did
demand, and low rainfall during the growing season. At
not lead to low greenness in Portugal. The M. sinensis
hybrid genotypes no. 7 and 9 are stay-green types. Such the other four sites, no irrigation was used in 1999.
Yields were highest at the German site, which had notstay-green traits are being investigated in other crops
(Thomas and Howarth, 2000; Xu et al., 2000) with a only the most rainfall in 1999, but also a heavy clay soil.
Because biomass production must be low cost and lowview to increasing yield. However, in northern regions
of Europe, the late-senescing genotypes (M. sinensis input, it is unlikely that irrigation will be economic, and
a combination of site and genotype selection will behybrids no. 7 and 9) yielded badly. Autumn frosts kill
the green leaves of late-maturing genotypes at northern important to ensure survival and adequate yields.
It is important to point out that biomass quality forsites. This may lead to insufficient relocation of nutrients
and assimilates from the aboveground shoots to the combustion improves if the crop is harvested in early
spring rather than in the previous autumn. Yields can,rhizomes in autumn, reducing both the overwintering
capacity and regrowth potential in the following spring however, be as much as 30% less in the following spring
due to death and detachment of leaves and stem tops(Pude et al., 1997). Interestingly, overwintering of Ge-
notypes no. 7 and 9 in Sweden and Denmark were the (Clifton-Brown et al., 2000; Jørgensen, 1997).
There is a potential weed risk from the diploid Mis-poorest of the M. sinensis hybrids (Table 4).
When genotypes that failed to overwinter in Sweden canthus genotypes in Europe because fertile seeds were
produced at all sites where flowering occurred. To date,and Denmark are omitted (Table 4), plant height was
the growing season performance characteristic most seedlings have not been found to spread far from the
plots, which have had frequently mown paths. Currenthighly correlated with yield (Table 6). Greater height
implies later flowering, and therefore, longer periods for breeding programs for Miscanthus spp. are attempting
to produce infertile hybrids (K.K. Petersen, personalwhich radiation is converted to biomass. Shoot densities
were not found to be significantly related to yield (Table communication, 2000).
CLIFTON-BROWN ET AL.: PERFORMANCE OF MISCANTHUS GENOTYPES IN EUROPE 1019
Clifton-Brown, J.C., B.M. Neilson, I. Lewandowski, and M.B. Jones.
CONCLUSIONS 2000. The modelled productivity of Miscanthus giganteus (GREEF
et DEU) in Ireland. Ind. Crops Prod. 12:97–109.
New plantations with M. giganteus and M. sacchari-
Greef, J.M., and M. Deuter. 1993. Syntaxonomy of Miscanthus
florus are unlikely to be viable where winter soil temper- giganteus GREEF et DEU. Angew. Bot. 67:87–90.
atures fall below 3C at a depth of 5 cm. In England Greef, J.M., M. Deuter, C. Jung, and J. Schondelmaier. 1997. Genetic
and Germany, M. giganteus genotypes were among diversity of European Miscanthus species revealed by AFLP finger-
the top performers. These genotypes yielded well in printing. Genet. Resources and Crop Evolution 44:185–195.
Hodkinson, T.R., S.A. Renvoize, and M.W. Chase. 1997. Systematics
Portugal, 34 t ha
1
, but the highest-yielding genotype in Miscanthus. Aspects Appl. Biol. 49:189–198.
in Portugal was the stay-green M. sinensis hybrid no. 7 Jones, M.B., and M. Walsh. 2001. Miscanthus—for energy and fibre.
(41 t ha
1
dry matter). The highest-yielding genotypes James and James (Science Publishers), London (in press).
in Sweden and Denmark were the M. sinensis hybrids Jørgensen, U. 1997. Genotypic variation in dry matter accumulation
and content of N, K, and Cl in Miscanthus in Denmark. Biomass
no. 6, 8, and 10. These results demonstrate that different Bioenergy 12:155–169.
M. sinensis hybrids can be found for a wide range of Lawlor, D.W. 1995. Photosynthesis, productivity, and environment.
climatic conditions in Europe. In mid-Europe, M. J. Exp. Bot. 46:1449–1461.
giganteus is still the genotype of preference. Plant height, Lewandowski, I., J.C. Clifton-Brown, J.M.O. Scurlock, and W. Huis-
man. 2000. Miscanthus: European experience with a novel energy
which is largely controlled by flowering time, was a more crop. Biomass Bioenergy 19:209–277.
important selection characteristic than shoot density. Linde-Laursen, I.B. 1993. Cytogenetic analysis of Miscanthus ‘Gigan-
teus’, an interspecific hybrid. Hereditas 119:297–300.
Matumura, M., T. Hasegawa, and Y. Saijoh. 1985. Ecological aspects
ACKNOWLEDGMENTS of Miscanthus sinensis var. condensatus, M. sacchariflorus,and
The authors thank Sabine Schneider, Birgit Beierl, and the their 3-, 4-hybrids: I. Process of vegetative spread. Res. Bull.
team at the Ihinger Hof field station for technical assistance Fac. Agric., Gifu Univ. 50:423–433.
Monteith, J.L. 1978. Reassessment of the maximum growth rates for
in the field in Germany. Kaj Eskesen is thanked for technical
C3 and C4 crops. Exp. Agric. 14:1–5.
assistance in the field in Denmark. Michael Sommer and Søren Nielsen, P.N. 1987. The productivity of Miscanthus sinensis ‘Gigan-
B. Torp are thanked for their work on the soil taxonomy. teus’ on different soil types. Tidsskr. Planteavl. 91:275–281.
Thanks also to Mike Jones for reading the manuscript. The Potter, L., M.J. Bingham, M.G. Baker, and S.P. Long. 1995. The
EMI project was funded by EU contract FAIR3 CT-96-1392. potential of two perennial C4 grasses and a perennial C4 sedge as
ligno-cellulosic fuel crops in N.W. Europe. Crop establishment and
yields in E. England. Ann. Bot. (London) 76:513–520.
REFERENCES Pude, R., H. Franken, W. Diepenbrock, and J.M. Greef. 1997. Ur-
Christian, D.G. 1994. Quantifying the yield of perennial grasses grown sachen der Auswinterung von einja
¨hrigen Miscanthus-Besta
¨nden.
as a biofuel for energy generation. Renewable Energy 5:762–766. Pflanzenbauwissenchaften 1:171–176.
Clifton-Brown, J.C., and M.B. Jones. 1997. The thermal response of Schwarz, H.U., D.P.L. Murphy, and E. Schnug. 1994. Studies of the
leaf extension rate in genotypes of the C4-grass Miscanthus:An growth and yield of M.giganteus in Germany. Aspects Appl.
important factor in determining the potential productivity of differ- Biol. 40:533–540.
ent genotypes. J. Exp. Bot. 48:1573–1581. Soil Survey Staff. 1999. Soil taxonomy—a basic system of soil classifi-
Clifton-Brown, J.C., and I. Lewandowski. 2000. Overwintering prob- cation for making and interpreting soil surveys. 2nd ed. USDA-
lems of newly established Miscanthus plantations can be overcome NRCS Agric. Handb. 436. U.S. Gov. Print. Office, Washington, DC.
by identifying genotypes with improved rhizome cold tolerance. Thomas, H., and C.J. Howarth. 2000. Five ways to stay green. J. Exp.
New Phytol. 148:287–294. Bot. 51:329–337.
Clifton-Brown, J.C., S.P. Long, and U. Jørgensen. 2001. Miscanthus Xu, W.W., P.K. Subudhi, O.R. Crasta, D.T. Rosenow, J.E. Mullet,
productivity. p. 46–67. In M.B. Jones and M. Walsh (ed.) Miscan- and H.T. Nguyen. 2000. Molecular mapping of QTLs conferring
thus—for energy and fibre. James and James (Science Publishers), stay-green in grain sorghum (Sorghum bicolor L. Moench). Ge-
nome 43:461–469.London (in press).
... M. sacchariflorus is found primarily in the temperate regions of Asia, including India, China, Korea, Japan, and eastern Russia [4][5][6]. Subsequent studies have shown that M. sacchariflorus possesses broad environmental adaptability, as it can propagate in a variety of climatic conditions ranging from sea level to 2000 m altitude, in diverse soil structures, with variable water and nitrogen content, and with minimal inputs [2,3,[7][8][9][10][11][12][13]. M. sacchariflorus typically grows in damp or wet soils near the edges of water sources, exhibits high spreading capacity due to its long rhizomes, and is considered a potential sustainable and renewable feed stock [2,3]. ...
... These results are in accordance with the reports of Yan et al. [60], in which a positive correlation between biomass and flowering time was reported in accessions of M. sacchariflorus. Moreover, late flowering increased the biomass production in M. sacchariflorus, but reduced the percentage of seed setting in M. sacchariflorus plants [3,10,62]. ...
... Winter survival rate or overwintering ability of first year M. sacchariflorus accessions was lower than in the subsequent growing seasons, with little or no damage occurring and vigorous growth. This finding is corroborated by the report of Clifton-Brown et al. [10], in which low survival rates of M. sacchariflorus accessions are reported in the winter. In similar studies, Clifton-Brown et al. [10] and Christian et al. [63] observed that accessions grown in the first year store less nutrients in the rhizome to survive the winter and have inadequate reserves with which to regenerate shoots in the following year. ...
Article
Full-text available
Miscanthus sacchariflorus is a potential source of sustainable biofuel and other bioactive compounds. The high adaptive range of M. sacchariflorus may cause variation in its morphological traits and phytochemical composition. Although some metabolites have been reported from M. sacchariflorus, little is known about its phenolic compound composition and antioxidant or oxidant properties. This study evaluated the morphological traits, antioxidant properties, and phenolic compound profile of M. sacchariflorus collected from various regions of China, Korea, Japan, and Russia. The antioxidant potential of the leaf extracts of various accessions of M. sacchariflorus was estimated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay and 2,2′-azinobis 3-ethylbenzothiazoline-6-sulfonate (ABTS). An extensive study of the antioxidant activity and phenolic compounds of M. sacchariflorus obtained from different locations in four different countries could provide a comprehensive catalogue of the phytoconstituents and antioxidant properties of M. sacchariflorus accessions to consumers and nutraceutical industries. A total of 22 phenolic compounds were identified and quantified, among which p-coumaric acid, ferulic acid, p-hydroxybenzoic acid, chlorogenic acid, vitexin, and luteolin were the most dominant phytochemical compounds detected in the majority of the accessions. The antioxidant potential (DPPH) of the leaf extracts of all of the accessions ranged from 28.85 ± 1.53 µg mL−1 in MS-447 to 99.25 ± 1.63 µg mL−1 in MS-190. The antioxidant properties (ABTS) of the leaf extracts of all accessions ranged from 25.65 ± 2.06 in MS-258 to 83.62 ± 2.02 in MS-271. Pearson’s correlation analysis showed a significant and positive correlation between antioxidant activity and total phenolic content, and total flavonoid content varied widely among M. sacchariflorus accessions from the four geographical study regions. A strong and positive association was observed between DPPH with total phenolic content and total flavonoid content. Moderately positive correlations were observed between DPPH scavenging activity with gentisic acid, p-hydroxybenzoic acid, chlorogenic acid, p-coumaric acid, rutin, and quercetin (r = 0.385, r = 0.379, r = 0.362, r = 0.353, r = 0.490, and r = 0.372, respectively), suggesting that phenolic compounds are major contributors to the antioxidant potential of M. sacchariflorus. Thirty-two accessions collected from four different countries (China, Korea, Japan, and Russia) were characterized for 17 quantitative morphological traits. A wide range of diversity was observed in the morphological traits, with plant height ranging from 18.00 ± 1.00 cm to 163.20 ± 4.00 cm. Plant height was significantly correlated with biomass yield (fresh weight; r = 0.439, p < 0.05) and also had moderately positive correlations with culm length (r = 0.356, p < 0.05). Culm length was moderately correlated with the biomass yield fresh weight (r = 0.419*, p < 0.05) and the biomass yield dry weight (r = 0.425*, p < 0.05); however, it exhibited weak and negative correlations with compressed plant circumference (CCirc) (r = −0.374, p < 0.05) and total culm node number (TCmN) (r = −0.440, p < 0.05). Principal components analysis was performed to assess the variation in 17 morphological traits in 32 accessions of M. sacchariflorus. The first two principal components explained 51.24% of the morphological variations. A dendrogram generated from unweighted pair group method with arithmetic mean (UPGMA) clustering based on morphological characters was not found to be consistent with another dendrogram based on phytochemicals. In both cases, the number of studied accessions collected from different geographical regions grouped into two major groups. However, no clear correlation between these two different approaches was found. The substantial variation in the morphological traits, bioactive properties, and phenolic compounds among the accessions may provide useful information for breeding programs attempting to obtain M. sacchariflorus varieties with improved phenolic compounds traits and improved bioactive properties.
... Of these, warm-season grasses, such as miscanthus (Miscanthus x giganteus Greef & Deuter ex Hodkinson & Renvoize), switchgras (Panicum virgatum L.) and giant reed (Arundo donax L.), have widely been accepted as dedicated bioenergy crops as a result of their higher level of biomass productivity, combustion quality, and resource use efficiency (land, water, fertiliser, and radiation) over cool-season grasses and annual crops under adequate soil water conditions (Lewandowski and Schmidt, 2006;Mantineo et al., 2009;Pedroso et al., 2014). However, poor establishment as well as low crop survival levels are the most challenging factors in achieving sustainable bioenergy production from these crops under low soil water availability conditions (Clifton-Brown et al., 2001;Vamvuka et al., 2010). Therefore, irrigation is often necessary to maintain high biomass productivity, but this type of production seems to generally not be economically viable and may threaten food security due to competition between bioenergy and food crops for water usage in semi-arid and arid areas which frequently suffer from prolonged and severe summer droughts (Clifton-Brown et al., 2001;Rost et al., 2008;Cosentino et al., 2014). ...
... However, poor establishment as well as low crop survival levels are the most challenging factors in achieving sustainable bioenergy production from these crops under low soil water availability conditions (Clifton-Brown et al., 2001;Vamvuka et al., 2010). Therefore, irrigation is often necessary to maintain high biomass productivity, but this type of production seems to generally not be economically viable and may threaten food security due to competition between bioenergy and food crops for water usage in semi-arid and arid areas which frequently suffer from prolonged and severe summer droughts (Clifton-Brown et al., 2001;Rost et al., 2008;Cosentino et al., 2014). As a result, these challenges have generated considerable interest on the use of high-yielding perennial cool-season grasses as alternative bioenergy feedstock that can produce satisfactory biomass yields with little or no irrigation in arid and semi-arid areas. ...
Article
In order to achieve economically viable and sustainable solid biofuel production from perennial grasses, high biomass productivity must be complemented by good combustion quality. The aim of this research was to compare the combustion quality of 7 cool-season perennial grasses, comprising bulbous canary grass, reed canary grass, smooth brome grass, orchard grass, tall wheatgrass, tall fescue, and perennial ryegrass, and 3 warm-season perennial grasses, comprising switchgrass, miscanthus, and giant reed, over 2 harvest times (autumn, winter/ early spring) in 2 contrasting semi-arid environments (Adana, and Cankiri, Turkey). Delaying the harvest from the autumn to the winter or the spring significantly increased the lignin contents of each of the 3 warm-season grasses and generally decreased the contents of all of the minerals, except for Al and Fe, in miscanthus and switchgrass, and K and Na in giant reed, at both locations. Similar trends were also generally observed for all of the cool-season grasses, except for the orchard grass that was grown in Cankiri. Additionally, delayed harvest resulted in lower slagging tendency and sintering risk in all of the perennial grass species, except for giant reed in Cankiri. However, the autumn harvest caused significantly higher lignin, but generally lower N, P, K, Ca, S, Si, Al, and Fe contents, slagging tendency, and sintering risk in most of the cool-season grasses that were grown in Adana. On the other hand, despite the autumn harvest in Adana, and the spring harvest in Cankiri provided a substantial improvement in combustion quality of the cool-season grasses, mainly due to the reduced mineral and increased lignin contents, they still exhibited relatively lower combustion quality than miscanthus and switchgrass, especially in Adana. These results showed that further effort is needed to improve the combustion quality of cool-season grasses in order for them to be primary biomass feedstock alternatives for dry marginal lands of semi-arid environments.
... The breeding of new miscanthus cultivars would make it possible to extend the genetic base in miscanthus breeding programs of western countries where it is mainly obtained from ornamental accessions originating from Japan [19,21]. This would be possible by crossing distinct ornamental cultivars or exploiting wild available germplasm [14,19,23]. ...
... For these traits, genotype × year interactions have been highlighted in a period covering at least 3 years after implantation. Genotype × location interactions have been evidenced as well: breeding efficiency has been shown to potentially increase if miscanthus genotypes are evaluated in different locations, as some genotypes reached a better biomass yield in one location compared to others [23,[28][29][30][31][32]. Other studies have observed genotype × year and genotype × location interactions while evaluating biomass composition traits, from at least the first to the third year after establishment [31,[33][34][35][36]. ...
Article
Full-text available
Traits for biomass production and composition make Miscanthus a promising bioenergy crop for different bioconversion routes. They need to be considered in miscanthus breeding programs as they are subjected to genetic and genetic × environment factors. The objective was to estimate the genetic parameters of an M. sinensis population grown during 4 years in two French locations. In each location, the experiment was established according to a staggered-start design in order to decompose the year effect into age and climate effects. Linear mixed models were used to estimate genetic variance, genotype × age, genotype × climate interaction variances, and residual variances. Individual plant broad-sense heritability means ranged from 0.42 to 0.62 for biomass production traits and were more heritable than biomass composition traits with means ranging from 0.26 to 0.47. Heritability increased through age for most of the biomass production and composition traits. Low genetic variance along with large genotype × age and genotype × climate interaction variances tended to decrease the heritability of biomass production traits for young plant ages. Most of the production traits showed large interaction variances for age and climate in both locations, while biomass composition traits highlighted large interaction variances due to climate in Orléans. The genetic and phenotypic correlations between biomass production and composition traits were positive, while hemicelluloses were negatively correlated with all traits. Selection is difficult on young plants as the heritability is too low. The joint improvement of biomass production and composition traits would help provide a better response of miscanthus to selection.
... In late autumn, M. × giganteus plants reallocate assimilates to the rhizomes in order to overwinter in regions of low temperature. Miscanthus can be grown at the same site for at least 20 years, which makes them highly efficient at long-term carbon sequestration [9,15]. ...
Article
Full-text available
Miscanthus × giganteus is a popular industrial plant with great potential in ecological agriculture. It forms numerous rhizomes that are important in the sequestration of carbon dioxide. The plant can be a source of lignin and cellulose, biomass for renewable energy production, and can be used in small garden architecture, or to strengthen the banks of landslides. Breeding this species is difficult, as it is a sterile allotriploid with 57 chromosomes. The aim of the study was to obtain fertile plants of this species by treating its callus and regenerants with chromosome doubling agents such as colchicine, oryzalin, trifluralin, and caffeine at variable concentrations and durations. Callus cells naturally showed large variations in the number of chromosomes but only euploid cells regenerated plants. Treatment of the regenerants with 1252 µM colchicine for 18 h allowed for obtaining two hexaploid shoots; however, they died before flowering. Colchicine and oryzalin stimulated the formation of mixoploid shoots. The investigated substances, except for caffeine, were highly toxic to plants. M. × giganteus plants with 114 chromosomes may die because such a high number of chromosomes may be unfavorable for cells of this species.
... The Miscanthus sinensis (Msin) species is interesting with regard to the expansion of the varietal offer: it presents a huge genetic variability [19], a better abiotic stress tolerance than M × g [20], phytoremediation activity [21] and intraspecific variability concerning occurrence dates of developmental stages and length of the growing season [22]. All these characteristics could allow to enlarge the production area while maintaining decent yields, from Mediterranean Europe such as Turkey to northern regions like Sweden [20,23]. Msin could potentially be cultivated on marginal lands with higher yields and under more stressful conditions than M × g [20]. ...
Article
Full-text available
Nitrogen (N) recycling is a key mechanism to ensure the sustainability of miscanthus production with no or small fertiliser inputs, but little is known on the subject in miscanthus species other than the most cultivated Miscanthus × giganteus. This field experiment on Miscanthus × giganteus and Miscanthus sinensis quantified plant biomass and N stock dynamics during two years. Endogenous net N fluxes, calculated from the evolution of plant N content throughout time, were higher in Miscanthus × giganteus than in Miscanthus sinensis. Indeed, 79 kg N ha⁻¹ and 105 to 197 kg N ha⁻¹ were remobilised during spring and autumn, respectively, for Miscanthus × giganteus, as opposed to 13 to 25 kg N ha⁻¹ and 46 to 128 kg N ha⁻¹ for Miscanthus sinensis. However, N recycling efficiency, defined as the ratio between N remobilisation fluxes and the maximum above-ground N content, did not differ significantly between the two species. N recycling efficiency ranged from 8 to 27% for spring remobilisation and from 63 to 74% and 24 to 38% for autumn remobilisation calculated on above-ground and below-ground N, respectively. Exogenous N, the main source of N to constitute maximum plant N content for all genotypes, was provided by fertilisation (22 to 24%) and organic matter mineralisation or other sources (43 to 59%). During winter, 42 to 56% of plant N content was lost. Only a small part of these plant N losses was due to abscised leaves (6–12% of the maximum plant N content). Our results show that Miscanthus sinensis is as efficient as Miscanthus × giganteus in N recycling and N use efficiency and as performant as other perennial species.
Article
Full-text available
Miscanthus is a leading perennial biomass crop that can produce high yields on marginal lands. Moisture content is a highly relevant biomass quality trait with multiple impacts on efficiencies of harvest, transport, and storage. The dynamics of moisture content during senescence and overwinter ripening are determined by genotype × environment interactions. In this paper, unmanned aerial vehicle (UAV)-based remote sensing was used for high-throughput plant phenotyping (HTPP) of the moisture content dynamics during autumn and winter senescence of 14 contrasting hybrid types (progeny of M. sinensis x M. sinensis [M. sin x M. sin, eight types] and M. sinensis x M. sacchariflorus [M. sin x M. sac, six types]). The time series of moisture content was estimated using machine learning (ML) models and a range of vegetation indices (VIs) derived from UAV-based remote sensing. The most important VIs for moisture content estimation were selected by the recursive feature elimination (RFE) algorithm and were BNDVI, GDVI, and PSRI. The ML model transferability was high only when the moisture content was above 30%. The best ML model accuracy was achieved by combining VIs and categorical variables (5.6% of RMSE). This model was used for phenotyp-ing senescence dynamics and identifying the stay-green (SG) trait of Miscanthus hybrids using the generalized additive model (GAM). Combining ML and GAM modeling, applied to time series of moisture content values estimated from VIs derived from multiple UAV flights, proved to be a powerful tool for HTPP. K E Y W O R D S GAM, high-throughput plant phenotyping, machine learning, Miscanthus, moisture content, multispectral, remote sensing, senescence, transferability, UAV
Article
Full-text available
Miscanthus × giganteus is a promising high-yielding perennial plant to meet growing bioenergy demands; however, the degree to which the soil microbiome affects its nitrogen cycling and subsequently, biomass yield remains unclear. In this study, we hypothesize that contributions of metabolically active soil microbial membership may be underestimated with DNA-based approaches. We assessed the response of the soil microbiome to nitrogen availability in terms of both DNA and RNA soil microbial communities from the Long-term Assessment of Miscanthus Productivity and Sustainability (LAMPS) field trial. DNA and RNA were extracted from 271 samples, and 16S small subunit (SSU) rRNA amplicon sequencing was performed to characterize microbial community structure. Significant differences were observed in the resulting soil microbiomes and were best explained by the sequencing library of origin, either DNA or RNA. Similar numbers of membership were detected in DNA and RNA microbial communities, with more than 90% of membership shared. However, the profile of dominant membership within DNA and RNA differed, with varying proportions of Actinobacteria and Proteobacteria and Firmicutes and Proteobacteria. Only RNA microbial communities showed seasonal responses to nitrogen fertilization, and these differences were associated with nitrogen-cycling bacteria. The relative abundance of bacteria associated with nitrogen cycling was 7-fold higher in RNA than in DNA, and genes associated with denitrifying bacteria were significantly enriched in RNA, suggesting that these bacteria may be underestimated with DNA-only approaches. Our findings indicate that RNA-based SSU characterization can be a significant and complementing resource for understanding the role of soil microbiomes in bioenergy crop production. IMPORTANCE Miscanthus × giganteus is a promising candidate for bioeconomy cropping systems; however, it remains unclear how the soil microbiome supplies nitrogen to this low-input crop. DNA-based techniques are used to provide community characterization, but may miss important metabolically active taxa. By analyzing both DNA- and actively transcribed RNA-based microbial communities, we found that nitrogen cycling taxa in the soil microbiome may be underestimated using only DNA-based approaches. Accurately understanding the role of microbes and how they cycle nutrients is important for the development of sustainable bioenergy crops, and RNA-based approaches are recommended as a complement to DNA approaches to better understand the microbial, plant, and management interactions.
Preprint
Full-text available
Traits for biomass production and composition make Miscanthus a promising bioenergy crop for different bioconversion routes. They need to be considered in miscanthus breeding programs as they are subjected to genetic and genetic x environment factors. The objective was to estimate the genetic parameters of an M. sinensis population grown during four years in two French locations. In each location, the experiment was established according to a staggered-start design in order to decompose the year effect into age and climate effects. Linear Mixed Models were used to estimate genetic variance, genotype x age, genotype x climate interaction variances and residual variances. Individual plant broad-sense heritability means ranged from 0.42 to 0.62 for biomass production traits, and were more heritable than biomass composition traits with means ranging from 0.26 to 0.47. Heritability increased through time for most of the biomass production and composition traits. Low genetic variance along with large genotype x age and genotype x climate interaction variances tended to decrease the heritability of biomass production traits for young plant ages. Most of the production traits showed large interaction variances for age and climate in both locations, while biomass composition traits highlighted large interaction variances due to climate in Orléans. The genetic and phenotypic correlations between biomass production and composition traits were moderate and positive, while hemicelluloses were negatively correlated with all traits. Efficient genetic progress is achievable for miscanthus breeding when plants get older. The joint improvement of biomass production and composition traits would help provide a better response of miscanthus to selection.
Preprint
Full-text available
Breeding miscanthus for biomass production and composition is essential for targeting high-yielding genotypes suited to different end-uses. Our objective was to understand the genetic determinism of these traits in M. sinensis , according to different plant ages and environmental conditions. A diploid population was established in two locations according to a staggered-start design, which made the “year” effect partitioned into “age” and “growing season” effects. An integrated genetic map of 2,602 SNP markers distributed across 19 LGs, was aligned with the M. sinensis reference genome and spanned 2,770 cM. The QTL mapping was based on Best Linear Unbiased Predictions estimated across three climatic conditions and at least three ages in both locations. 260 and 283 QTL were related to biomass production and composition traits, respectively. In each location, 40%-60% were related to biomass production traits and stable across different climatic conditions and ages, and 30% to biomass composition traits. Ten to fifteen% were stable for both trait types across locations. Twelve QTL clusters were established based on either biomass production or composition traits, and validated by high genetic correlations between the traits. Sixty-two putative M. sinensis genes, related to the cell-wall, were evidenced in the QTL clusters of biomass composition traits, and orthologous to those of sorghum and maize. Twelve of them were differentially expressed and belonged to gene families related to the cell-wall biosynthesis identified in other miscanthus studies. These stable QTL constitute new insights into Marker-Assisted Selection breeding while offering a joint improvement of biomass production or composition traits.
Article
Full-text available
Napier grass is a tropical perennial C4 grass with superior biomass yield and quality. It is an important forage crop and a promising feedstock for lignocellulosic biofuel production. However, precise phenotyping and genotyping data to support the molecular breeding of napier grass are scarce. A napier grass F1 mapping population (segregating pseudo-F2 population) was generated by hybridizing genetically distant parents (N190×N122) with contrasting flowering time- and biomass-related traits. True F1 hybrids were confirmed with a simple sequence repeat marker, vegetatively propagated and phenotyped in replicate field plots for 2 years (2 harvests per year) in Citra, FL, USA (29.40 N). Near-normal distributions were observed for flowering date, plant height, number of tillers, stem diameter, and leaf width, confirming the quantitative nature of these traits. The annual dry biomass yield of F1 hybrids varied between 21.0 and 41.1 t ha⁻¹. The highest-yielding F1 hybrids showed remarkable hybrid vigor exceeding the annual biomass production of the highest-yielding parental accession (26.9 t ha⁻¹) by 52% and the biomass yield of the control ‘Merkeron’ cultivar (29.2 t ha⁻¹) by 41% over 2 years. F1 hybrids with delayed flowering time along with significantly increased biomass yield were also identified. Late-flowering accessions allowed maximum biomass harvest before the occurrence of seed formation and dispersal for enhanced biosafety. The developed mapping population will be an excellent resource for identifying quantitative trait loci and candidate genes for flowering- and biomass-related traits in napier grass that will accelerate the improvement of this nondomesticated bioenergy crop.
Article
Full-text available
The relation between photosynthetic rate per unit leaf area (Pn), total photosynthesis by canopies and dry matter production (DMP) of crops is reviewed. Although Pn is the driving force for all plant growth, total DMP is determined by processes integrated over the canopy, primarily light interception and thus by leaf area index (LAI) and canopy architecture and leaf area duration (LAD). The processes are not linearly related so that effects on DMP of changes in the efficiency of conversion of energy of radiation to dry matter are smaller than those associated with LAI. Photosynthesis is much less sensitive to changing environmental conditions than development of leaf area. This explains the apparent anomaly that Pn does not determine the variation in productivity of a crop under normal agronomic practice, despite the role of photosynthesis in providing all the assimilates for DMP. Breeding and selection of crops for higher yield has not resulted in improvements in dry matter production. Indeed, potential photosynthetic rate has decreased under selection breeding, compensated by increased leaf area: the causes are considered. Crops growing at or near their potential rate use most of the available solar energy and there is a strong correlation between radiation absorbed and DMP and canopy photosynthesis is not light saturated. To increase production it will be necessary to extend either the growing season or to improve light conversion efficiency; the latter is best achieved by increasing Pn. The limiting factors in photosynthetic metabolism which determine Pn under different environmental conditions, are reviewed. Increased Pn is not likely to come from altering light harvesting, electron transport or ATP and NADPH synthesis which are potentially very flexible and have large capacity: there is large genetic variation. Synthesis of ribulose bisphosphate (RuBP) depends on activity of Calvin cycle enzymes which may be limiting due to environmental factors. Increasing the atmospheric CO2 supply increases production of C3 plants under current conditions: this is due to a decrease in the oxygenase function of ribulose bisphosphate carboxylase-oxygenase (Rubisco). Improving the specificity factor of Rubisco is a long-term goal to decrease photorespiration. Even if Pn is increased, evidence from theoretical and crop canopy studies suggest that the increase in biomass production will only be a small proportion of the increase in Pn, and DMP also depends on the crop's sink capacity. Crop production is a function of many processes, at the level of the chloroplast, the leaf and the canopy. To increase Pn and production of crops will require knowledge of processes at all levels in the plant-environment system.
Article
Full-text available
Thermal responses of plant extension rate are reported for 32 genotypes of the C4 grass Miscanthus. Displacement transducers were used to measure plant extension rate as temperatures were stepped between 20°C and 5°C. Leaf extension accounted for 83% of the plant extension. The Q10 between 10°C and 20°C for the genotypes varied from 3.0 to 4.7. The relationship between temperature (5-20 °C) and plant extension rate was found to be described adequately by fitting a third order polynomial. An estimate of the effect of differences in the thermal response of plant extension rate on the potential yield of the genotypes was calculated for Irish climatic conditions using a simple growth model. Potential yield varied between 3 and 23 t ha−1 year−1. This demonstrates the critical role which differences in leaf expansion rate can play in the selection of more productive genotypes. The significance of vapour pressure deficit on the estimates of thermal response of plant extension rate are discussed.
Article
European experiments on Miscanthus have so far been concentrated on one genotype, namely the triploid, infertile hybrid M. “Gitanteus”. Chemical analysis of this genotype has shown relatively high mineral contents which reduce its quality for power production. This paper presents the yields and concentrations of N, K and Cl in 15 selections of the species M. sinensis, and compares these to data on M. “Giganteus”. Yields were rather low during the experimental period 1992–1995 due to adverse climatic conditions. Average dry matter yield over three years of measurements at spring harvest was 8.9 t/ha for M. sinensis selections and 7.7 t/ha for M. “Giganteus”. The percentage content of N, K and Cl in plant dry matter as a mean of three years was 0.64, 0.39 and 0.08 in the M. sinensis selections and 0.59, 0.81 and 0.33 in M. “Giganteus”. There were large variations in yield and mineral concentrations within the selections of M. sinensis, and some of the selections seem to meet the target fuel specification values for K and Cl content set by the Danish Power Pools. During 1994/1995, plant material was sampled almost monthly from M. “Giganteus” and from two selections of M. sinensis. Mineral concentrations were of the same order of magnitude in the three genotypes during most of the growing season. However, during the winter, the K and Cl content decreased more in M. sinensis than in M. “Giganteus”. In the Danish climate only M. sinensis flowers and shows physiological senescence, while M. “Giganteus” stays in the vegetative stage until it is killed by the frost. This is probably part of the reason for the difference between genotypes in K and Cl lability, but the possible influence of other factors is also discussed. The genotypical variation found in Miscanthus can be used in a breeding programme to create genotypes to match different climatic conditions and to produce biomass of specific qualities.
Article
Combustible biomass fuels may be produced on set-aside land by growing crops that produce a heavy yield of dry matter. Two promising candidate species are Miscanthus and Switchgrass. Establishment of both species was slow and weeds may cause problems. Yields were low because of the short growing period in the first season. Nitrate leaching under Miscanthus suggested that N levels were too high relative to the crops development.
Article
Figures for maximum crop growth rates, reviewed by Gifford (1974), suggest that the productivity of C3 and C4 species is almost indistinguishable. However, close inspection of these figures at source and correspondence with several authors revealed a number of errors. When all unreliable figures were discarded, the maximum growth rate for C3 stands fell in the range 34–39 g m−2 d−1 compared with 50–54 g m−2 d−1 for C4 stands. Maximum growth rates averaged over the whole growing season showed a similar difference: 13 g m−2 d−1 for C3 and 22 g m−2 d−1 for C4. These figures correspond to photosynthetic efficiencies of approximately 1·4 and 2·0%.
Article
Miscanthus, a perennial rhizomatous C4 grass, is a potential biomass crop in Europe, mainly because of its high yield potential and low demand for inputs. However, until recently only a single clone, M.×giganteus, was available for the extensive field trials performed across Europe and this showed poor overwintering in the first year after planting at some locations in Northern Europe. Therefore, field trials with five Miscanthus genotypes, including two acquisitions of Miscanthus×giganteus, one of M. sacchariflorus and two hybrids of M. sinensis were planted in early summer 1997 at four sites, in Sweden, Denmark, England and Germany. The field trials showed that better overwintering of newly established plants at a site was not apparently connected with size or early senescence. An artificial freezing test with rhizomes removed from the field in January 1998 showed that the lethal temperature at which 50% were killed (LT50) for M.×giganteus and M. sacchariflorus genotypes was −3.4 °C. However, LT50 in one of the M. sinensis hybrid genotypes tested was −6.5 °C and this genotype had the highest survival rates in the field in Sweden and Denmark. Although the carbohydrate content of rhizomes, osmotic potential of cell sap and mineral composition were not found to explain differences in frost tolerance adequately, moisture contents correlated with frost hardiness (LT50) in most cases. The results obtained form a basis for identifying suitable Miscanthus genotypes for biomass production in the differing climatic regions of Europe.
Article
The genetic diversity of European species of Miscanthus was analyzed by AFLP technique. The genetic similarity based on six primer combinations yielded about 200 data points. The plant material included 11 clones of M. sinensis, 2 clones of M. sacchariflorus and 31 accessions of M. x giganteus. Furthermore 4 hybrids were created by crossing M. sinensis with M. sacchariflorus clones. Two clusters were found represented by M. sinensis and M. sacchariflorus clones. The M. x giganteus accessions clustered under M. sacchariflorus. A very low genetic diversity was found in the M. x giganteus pool. No polymorphism was detected between micro- and rhizome-propagated M. x giganteus accessions. Many of the M. sacchariflorus clones sampled in Botanical Gardens turned out to be M. x giganteus clones. In the hybridization of M. sinensis and M. sacchariflorus material, self-fertilization of the M. sinensis clones was determined by application of the AFLP technique. In the M. sinensis pool a typical diversification of hybrids was detected according to ornamental selection by horticulture breeders. The AFLP technique is an adequate and powerful tool to evaluate genetic diversification, to analyse the success of hybridizations and to find wrong classifications.