agreement with the previous conclusions of
Landolt (1986) and Les et al. (2002). The alternative explanation is that the mutation rates in
the species of this section are higher.
It is remarkable that the internal structure of
the genus Lemna evaluated by GBS is almost
identical to the structure evaluated on the basis of
morphological and phytochemical markers (Les
et al. 1997). All four sections were revealed as
monophyletic taxa and evaluated by very high
posterior probabilities. This confirms the conclusion of Les et al. (2002) which was drawn on
the basis of different PCR fragments. The high
resolution of the GBS markers in the genus
Lemna also indicates that the section levels
should be revised (Fig. 11.2). For example, to
merge L. section Alatae and L. section Biformes
or to separate L. section Lemna into several
subsections. As the number of clones investigated per species in the present study remains
small, the diversity within and between species
might have some gaps. By the same reasons, it
cannot be decided whether all ten species of the
genus Lemna outside of L. section Uninerves
should be considered as independent species.
Therefore, to finalise the revision of the sections,
we are expanding our current study by including
more clones per species.
Acknowledgements The technical assistance of Susanne
König, Ines Walde, Sandra Drießlein, and Christa Fricke
(all IPK Gatersleben, Germany) is highly acknowledged.
We also thank Ingo Schubert from IPK Gatersleben, who
had provided access to the molecular methods and Walter
Laemmler, Landolt Duckweed Collection, Zürich, for
providing some clones.
References
Appenroth KJ, Teller S, Horn M (1996) Photophysiology
of turion formation and germination in Spirodela
polyrhiza. Biol Plant 38:95–106. https://doi.org/10.
1007/BF02879642
Bog M, Baumbach H, Schween U, Hellwig F, Landolt E,
Appenroth KJ (2010) Genetic structure of the genus
Lemna L. (Lemnaceae) as revealed by amplified
fragment length polymorphism. Planta 232:609–619.
https://doi.org/10.1007/s00425-010-1201-2
Bog M, Sree KS, Fuchs J, Hoang PTN, Schubert I,
Kuever J, Rabenstein A, Paolacci S, Jansen MAK,
Appenroth KJ (2020) A taxonomic revision of Lemna
sect. Uninerves (Lemnaceae). Taxon (in press)
Borisjuk N, Chu P, Gutierrez R, Zhang H, Acosta K,
Friesen N, Sree KS, Garcia C, Appenroth KJ, Lam E
(2015) Assessment, validation and deployment strategy of a two-barcode protocol for facile genotyping of
duckweed species. Plant Biol 17(Suppl. 1):42–49.
https://doi.org/10.1111/plb.12229
Bouckaert R, Heled J, Kühnert D, Vaughan T, Wu CH,
Xie D, Suchard MA, Rambaut A, Drummond AJ (2014)
BEAST 2: a software platform for Bayesian evolutionary analysis. PLoS Comput Biol 10(4):e1003537.
https://doi.org/10.1371/journal.pcbi.1003537
Bryant D, Bouckaert R, Felsenstein J, Rosenberg NA,
RoyChoudhury A (2012) Inferring species trees directly
from biallelic genetic markers: bypassing gene trees in
a full coalescent analysis. Mol Biol Evol 29(8):1917–
1932. https://doi.org/10.1093/molbev/mss086
Crawford DJ, Landolt E, Les DH (1996) An allozyme
study of two sibling species of Lemna (Lemnaceae)
with comments on their morphology, ecology and
distribution. Bull Torrey Bot Club 123(1):1–6. https://
doi.org/10.2307/2996300
Danecek P, Auton A, Abecasis G, Albers CA, Banks E,
DePristo MA, Handsaker RE, Lunter G, Marth GT,
Sherry ST, McVean G, Durbin R, 1000 Genomes
Project Analysis Group (2011) The variant call format
and VCFtools. Bioinformatics 27(15):2156–2158.
https://doi.org/10.1093/bioinformatics/btr330
Darriba D, Taboada GL, Doallo R, Posada D (2012)
jModelTest 2: more models, new heuristics and
parallel computing. Nat Methods 9:772. https://doi.
org/10.1038/nmeth.2109
Elshire RJ, Glaubitz JC, Sun Q, Poland JA, Kawamoto K,
Buckler ES, Mitchell SE (2011) A robust, simple
genotyping-by-sequencing (GBS) approach for high
diversity species. PLoS ONE 6(5):e19379. https://doi.
org/10.1371/journal.pone.0019379
Huelsenbeck JP, Ronquist F (2001) MrBayes: Bayesian
inference of phylogenetic trees. Bioinformatics 17(8):
754–755. https://doi.org/10.1093/bioinformatics/17.8.
754
Landolt E (1986) The family of Lemnaceae—a monographic study. Vol. 1. Biosystematic Investigations in
the Family of Duckweeds (Lemnaceae). Zürich:
Stiftung Ruebel
Landolt E (1998) Lemna yungensis, a new duckweed
species from rocks of the Andean Yungas in Bolivia.
Bullet Geobotanical Inst ETH 64:15–21
Les DH, Crawford DJ, Landolt E, Gabel JD, Kimball RT
(2002) Phylogeny and systematics of Lemnaceae, the
duckweed family. Syst Bot 27(2):221–240
Les DH, Landolt E, Crawford DJ (1997) Systematics of
the Lemnaceae (duckweeds): inferences from micromolecular and morphological data. Plant Syst Evol
204:161–177
Li H, Durbin R (2009) Fast and accurate short read
alignment with Burrows–Wheeler transform. Bioinformatics 25(14):1754–1760. https://doi.org/10.1093/
bioinformatics/btp324
122
M. Bog et al.
Landolt (1986) and Les et al. (2002). The alternative explanation is that the mutation rates in
the species of this section are higher.
It is remarkable that the internal structure of
the genus Lemna evaluated by GBS is almost
identical to the structure evaluated on the basis of
morphological and phytochemical markers (Les
et al. 1997). All four sections were revealed as
monophyletic taxa and evaluated by very high
posterior probabilities. This confirms the conclusion of Les et al. (2002) which was drawn on
the basis of different PCR fragments. The high
resolution of the GBS markers in the genus
Lemna also indicates that the section levels
should be revised (Fig. 11.2). For example, to
merge L. section Alatae and L. section Biformes
or to separate L. section Lemna into several
subsections. As the number of clones investigated per species in the present study remains
small, the diversity within and between species
might have some gaps. By the same reasons, it
cannot be decided whether all ten species of the
genus Lemna outside of L. section Uninerves
should be considered as independent species.
Therefore, to finalise the revision of the sections,
we are expanding our current study by including
more clones per species.
Acknowledgements The technical assistance of Susanne
König, Ines Walde, Sandra Drießlein, and Christa Fricke
(all IPK Gatersleben, Germany) is highly acknowledged.
We also thank Ingo Schubert from IPK Gatersleben, who
had provided access to the molecular methods and Walter
Laemmler, Landolt Duckweed Collection, Zürich, for
providing some clones.
References
Appenroth KJ, Teller S, Horn M (1996) Photophysiology
of turion formation and germination in Spirodela
polyrhiza. Biol Plant 38:95–106. https://doi.org/10.
1007/BF02879642
Bog M, Baumbach H, Schween U, Hellwig F, Landolt E,
Appenroth KJ (2010) Genetic structure of the genus
Lemna L. (Lemnaceae) as revealed by amplified
fragment length polymorphism. Planta 232:609–619.
https://doi.org/10.1007/s00425-010-1201-2
Bog M, Sree KS, Fuchs J, Hoang PTN, Schubert I,
Kuever J, Rabenstein A, Paolacci S, Jansen MAK,
Appenroth KJ (2020) A taxonomic revision of Lemna
sect. Uninerves (Lemnaceae). Taxon (in press)
Borisjuk N, Chu P, Gutierrez R, Zhang H, Acosta K,
Friesen N, Sree KS, Garcia C, Appenroth KJ, Lam E
(2015) Assessment, validation and deployment strategy of a two-barcode protocol for facile genotyping of
duckweed species. Plant Biol 17(Suppl. 1):42–49.
https://doi.org/10.1111/plb.12229
Bouckaert R, Heled J, Kühnert D, Vaughan T, Wu CH,
Xie D, Suchard MA, Rambaut A, Drummond AJ (2014)
BEAST 2: a software platform for Bayesian evolutionary analysis. PLoS Comput Biol 10(4):e1003537.
https://doi.org/10.1371/journal.pcbi.1003537
Bryant D, Bouckaert R, Felsenstein J, Rosenberg NA,
RoyChoudhury A (2012) Inferring species trees directly
from biallelic genetic markers: bypassing gene trees in
a full coalescent analysis. Mol Biol Evol 29(8):1917–
1932. https://doi.org/10.1093/molbev/mss086
Crawford DJ, Landolt E, Les DH (1996) An allozyme
study of two sibling species of Lemna (Lemnaceae)
with comments on their morphology, ecology and
distribution. Bull Torrey Bot Club 123(1):1–6. https://
doi.org/10.2307/2996300
Danecek P, Auton A, Abecasis G, Albers CA, Banks E,
DePristo MA, Handsaker RE, Lunter G, Marth GT,
Sherry ST, McVean G, Durbin R, 1000 Genomes
Project Analysis Group (2011) The variant call format
and VCFtools. Bioinformatics 27(15):2156–2158.
https://doi.org/10.1093/bioinformatics/btr330
Darriba D, Taboada GL, Doallo R, Posada D (2012)
jModelTest 2: more models, new heuristics and
parallel computing. Nat Methods 9:772. https://doi.
org/10.1038/nmeth.2109
Elshire RJ, Glaubitz JC, Sun Q, Poland JA, Kawamoto K,
Buckler ES, Mitchell SE (2011) A robust, simple
genotyping-by-sequencing (GBS) approach for high
diversity species. PLoS ONE 6(5):e19379. https://doi.
org/10.1371/journal.pone.0019379
Huelsenbeck JP, Ronquist F (2001) MrBayes: Bayesian
inference of phylogenetic trees. Bioinformatics 17(8):
754–755. https://doi.org/10.1093/bioinformatics/17.8.
754
Landolt E (1986) The family of Lemnaceae—a monographic study. Vol. 1. Biosystematic Investigations in
the Family of Duckweeds (Lemnaceae). Zürich:
Stiftung Ruebel
Landolt E (1998) Lemna yungensis, a new duckweed
species from rocks of the Andean Yungas in Bolivia.
Bullet Geobotanical Inst ETH 64:15–21
Les DH, Crawford DJ, Landolt E, Gabel JD, Kimball RT
(2002) Phylogeny and systematics of Lemnaceae, the
duckweed family. Syst Bot 27(2):221–240
Les DH, Landolt E, Crawford DJ (1997) Systematics of
the Lemnaceae (duckweeds): inferences from micromolecular and morphological data. Plant Syst Evol
204:161–177
Li H, Durbin R (2009) Fast and accurate short read
alignment with Burrows–Wheeler transform. Bioinformatics 25(14):1754–1760. https://doi.org/10.1093/
bioinformatics/btp324
122
M. Bog et al.