Preview content only
Content available from Genetic Resources and Crop Evolution
This content is subject to copyright. Terms and conditions apply.
A multivariate analysis of morphological divergence
of ‘‘seeds’’ (achenes) among ruderal, ﬁbre, oilseed,
dioecious/monoecious and marijuana variants of Cannabis
Steve G. U. Naraine .Ernest Small .Andrew E. Laursen .
Lesley G. Campbell
Received: 30 April 2019 / Accepted: 21 October 2019 / Published online: 30 October 2019
ÓSpringer Nature B.V. 2019
Abstract Cannabis sativa has been domesticated for
stem ﬁbre and oilseed (the two classes are both low in
the euphoric cannabinoid THC and called ‘‘hemp’’),
and marijuana (high in THC), and also occurs as
weedy, ruderal plants. Achenes (‘‘seeds’’) from
herbarium collections representative of these classes
were assessed for morphological characters and peri-
carp resistance to fracture. In contrast to ruderal plants,
domesticated plants (both hemp and marijuana) pos-
sessed achenes that were signiﬁcantly longer, heavier,
covered with a less adherent perianth, and lacking a
pronounced basal attenuation. All of these character-
istics reﬂect traits that are advantageous in domesti-
cated plants and are consistent with the
‘‘domestication syndrome’’ found in propagules of
other crops. Marijuana achenes, in comparison with
hemp achenes, tended to be about 26% shorter and
about 32 shades darker (on a 256-bit grayscale).
Achenes of ﬁbre cultivars proved to be about 19%
longer than the achenes of oilseed cultivars. Achenes
of dioecious oilseed cultivars proved to be about 6%
longer than the achenes of monoecious oilseed culti-
vars. The pericarps of hemp seeds were about 26% and
about 15% more resistant to fracture than those of
ruderal and marijuana plants, respectively.
Keywords Achenes Domestication Cannabis
sativa Ditchweed Hemp Marijuana
Taxonomic variation and domestication history
Cannabis is usually considered to have one species, C.
sativa L., although the names C. indica Lamarck
(usually designating marijuana strains) and C. ruder-
alis Janischevsky (usually labelling ruderal popula-
tions) are also encountered in the literature. Various
infraspeciﬁc classiﬁcations are also encountered (re-
viewed in Small, 2015,2016,2017). All biotypes of C.
sativa appear to be completely interfertile and there
are no genetic barriers to interbreeding (Small 1972).
Prodigious quantities of pollen are produced and
distributed by wind over considerable distances (Small
and Antle 2003), so spontaneous matings among
populations have doubtless homogenized the gene
pool of C. sativa (Gilmore et al. 2003; Dufresnes et al.
2017). Moreover, humans have very extensively
deliberately cross-pollinated traditional land races
S. G. U. Naraine A. E. Laursen L. G. Campbell (&)
Department of Chemistry and Biology, Ryerson
University, 350 Victoria St, Toronto, ON M5B 2K3,
S. G. U. Naraine E. Small
Ottawa Research and Development Centre, Agriculture
and Agri-Food Canada, Central Experimental Farm,
Ottawa, ON K1A 0C6, Canada
Genet Resour Crop Evol (2020) 67:703–714