Influences of intercropping on productivity and profitability of greater yam (Dioscorea alata L.)

Abstract

Greater yam (Dioscorea alata L.) is the widely distributed species of yams, and is an important food crop in tropical regions, cultivated for the consumption of their starchy tubers. The crop is normally planted at a distance of 90 cm x 90 cm and the crop takes about 3-4 months for proper establishment of the canopy after sprouting . Field experiments were conducted at five locations of different agro ecological conditions of India during 2015-16 and 2016-17 to assess the production potential and profitability of different greater yam based intercropping systems, to make use of the spatial and temporal availability of resources during the initial establishment period. Field corn (Zea mays L.), sorghum [Sorghum bicolor (L.) Moench] and pigeon pea [Cajanus cajan (L.) Millsp.] were intercropped with yam in 1:2 ratio at a spacing of 60 × 30 cm and trailing yam vines on intercrops. Pooled data analysis indicated that the maximum yam-equivalent yield (26.05 tha -1 ), land-equivalent ratio (1.46), net income (3,59,146/-) and B:C ratio (4.12) were obtained with greater yam + maize intercropping in all the locations. Intercropping could result in 31.5% land saving, comparable yam equivalent yields and up to 49% increase in net income compared to sole crop. Hence maize which is a starch rich crop can be profitably inter cropped with greater yam which is another food and nutrition security crop without sacrificing the main crop stand and yield. Maize stalks after harvests of cobs can act as stakes for yam vines also.