Among the landraces studied,‘Brazil Amazonia’,‘Columbia Gold’,‘Hoa Bac
Silver’, and‘Kilamanjaro’, originated from Brazil, Columbia, Vietnam, and Africa,
respectively. Morphologically,‘Hoa Bac Silver’and‘Kilamanjaro’were distinct
from each other and from the South American strains. In particular, the leaflets of
‘Kilamanjaro’were very narrow and the inflorescence was unlike any seen in
cultivated cannabis strains (Fig.19.4), with very fewflowers and no visible tri-
chomes. There were few morphological differences between the‘Brazil Amazonia’
and‘Columbia Gold’strains.‘Brazil Amazonia’produced the highest THC levels
among all the 4 landraces tested at 15%, while ‘Kilimanjaro’ produced the
second-highest THC levels at 14%.‘Columbia Gold’‘Hoa Bac Silver’produced 11
and 12%, respectively. None of the landraces contained any measurable CBD.
When these landraces and other strains were subjected to ISSR analysis using
the primers listed in Table19.1, followed by phylogenetic analysis to determine
genetic relatedness,‘Kilimanjaro’,‘Afghani’and‘Hao Bac Silver’formed a sep-
arate clade and were distinctly separated from the others, while‘Columbia Gold’
and‘Brazil Amazonia’were grouped in a different clade (Fig.19.5). This molecular
analysis supported the morphological distinctions observed within this group of
landraces.
The banding patterns produced by primers UBC 807 and UBC 817 are shown in
Figs.19.6and19.7. They show unique banding patters (DNAfingerprints) for all
of the landraces, including some from the same geographic location i.e. two col-
lections of‘Columbia Gold’and two of‘Brazil Amazonia’and‘Hao Bac Silver’
were shown to be different from each other with regard to the banding patterns
observed on the gels. This indicates that landraces presumed to be of the same
genetic background (hence given the same name) may actually be comprised of
different genetic composition, depending on where and when the collection was
made. The banding patterns ranged from complex (Fig.19.6) to simple (Fig.19.7),
depending on the primers used.
Additional ISSR analysis was conducted on marihuana strains obtained from a
wide range of sources, many of which are used in commercial production. Banding
pattern differences were observed, the number and frequency of which was
dependent on the primers (Fig.19.8). Interestingly, three samples of the strain
‘Sour G’from different sources showed variation in banding patterns. Following the
phylogenetic analysis, the three samples of‘Sour G’were placed in different
subgroups (Fig.19.8). A closer examination of the results indicated that one of the
‘Sour G’samples may have been a‘White OG’as the banding patterns were
identical and the strains were grouped together. A second‘Sour G’sample grouped
with a‘Pink Kush’strain (Fig.19.9).
Additional ISSR analysis conducted with a range of different marihuana strains
showed the potential for detecting variation within four strains all labeled as‘Qush’
originating from different sources (Fig.19.10). This suggests that within a named
strain, there can be genetic differences depending on how the strain was developed
through genetic crosses conducted under different environments, and the parentages
included in the development of the strain. Conversely, the ISSR method also
confirmed the genetic identity of two strains‘Jilly Bean’ and ‘Grape Kush’
19 Assessing Genetic Diversity inCannabis sativa... 405