Lepidium Meyenii - Botanical Characteristics

Botanical Characteristics

The species was first described by Gerhard Walpers in 1843 as Lepidium meyenii. In the 1990s Dr. Gloria Chacon made a further distinction of different species. She considered the widely cultivated natural maca of today to be a newer domesticated species, L. peruvianum. However, most botanists today doubt this distinction and continue to call the cultivated maca L. meyenii. The Latin name recognized by the USDA also continues to be Lepidium meyenii. There is a still ongoing debate about the correct nomenclature, and whether the distinction between meyenii and peruvianum is actually botanically correct or if they are the same species.

The growth habit, size, and proportions of maca are roughly similar to those of the radish and the turnip, to which it is related. The green, fragrant tops are short and lie along the ground. The thin, frilly leaves sprout in a rosette at the soil surface, not growing over 12 to 20 cm in height. The leaves show a dimorphism according to reproductive stage. They are more prominent in the vegetative phase, and are continuously renewed from the center as the outer leaves die. The off-white, self-fertile flowers are borne on a central raceme, and are followed by 4–5 mm siliculate fruits, each containing two small (2-2.5 mm) reddish-gray ovoid seeds. Seeds are the maca’s only means of reproduction. Maca reproduces mainly through self-pollination and is an autogamous species. The genome consists of 2n=8x=64 chromosomes. From experiments with different day lengths it can be concluded that maca is a short-day plant. Some sources consider the maca to be an annual plant, as in favorable years it can complete a life cycle within a year.