Arachis hypogaea L., a member of the legume family (Fabaceae), is an annual that measures about 30—50 cm in height (Figure 103.1). The leaves are alternate and pinnate with four leaflets (two opposite pairs; no terminal leaflet); each leaflet is 1—7 cm long and 1—3 cm broad. Peanut flowers are borne in axillary clusters above the ground. After the flowers have been pollinated, a short, thick stem at the flower base, termed the gynophore, grows downward and penetrates into the soil, so the fruiting body develops entirely underground. The pods, usually containing from one to three seeds, develop only underground. Each seed is covered with a thin papery seed coat. The peanut has a well-developed taproot, with numerous lateral roots that extend several inches into the ground. Most roots have nodules. The plant prefers light, well-drained, sandy loams, but will grow in heavier soils.
Peanut (Arachis hypogaea) (Köhler, 1887).
Was this article helpful?