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Maca (Lepidium meyenii) - cultivation, resistance and composition
µmol/g TS
Composition and amount of secondary metabolites were intensively analysed. In
leaves and roots, maca contains large quantities of glucosinolates (Figure 1). Glucotropaeoline
is the main glucosinolate with quantities of around 20 µmol/g ds in leaves
and up to 195 µmol/g ds in roots. In addition, other glucosinolates were found in
smaller amounts: sinalbine, X8-benzylglucosinolate, 4-hydroxy-glucobrassicine, X6benzylglucosinolate
and 4-methoxy-glucobrassicine. Glucosinolates X6 and X8 have
not been identified so far. Both origins differ likewise quantitatively, but not qualitatively
(Figure 2).
In maca also small quantities of flavonoids were determined. Up to now both substances
were not identified (Figure 3). No volatile substances could be found.
Resistance to phytopathogens important in crops of the genus Brassica was tested:
Alternaria blight, black leg and leaf spots, clubroot and virus disease caused by Alternaria
brassicae and A. brassicicola, Phoma lingam, Plasmodiophora brassicae
and turnip mosaic virus (TuMV), respectively. The tested accessions were susceptible
to all these pathogens.
Maca flavour was tested organoleptically. It has a pungent smell and sharp stinging
sensations after chewing.
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203-leaf 204-leaf 203-root 204-root
SINA X8 4-OH GTP X6 4-OCH3 GG
Fig. 2: Glucosinolate content and distribution patterns in leaves and roots of
two different origins of maca
SINA - sinalbine, X8 - benzylglucosinolate, 4-OH - 4-hydroxy-glucobrassicine,
GTP - glucotropaeoline, X6 - benzylglucosinolate, 4-OCH3 - 4-ethoxy-glucobrassicine,
X6 and X8 are not yet identified, GG - glucosinolates in total