Plant population and sett size effects on white yam (Dioscorea rotundata Poir.) intercropped in coconut garden

Abstract

African white yam (Dioscorea rotundata Poir.) a recent introduction to India, is gaining popularity due to its high yield potential, acceptable tuber quality, novel taste, and feasibility in diverse cropping systems. The most serious constraint to yam cultivation is the high production cost due to high planting material requirement. Cultural manipulation helps a great deal in minimizing the production cost in yams. Hence, the present research was undertaken to standardize plant population and sett size of white yam for economic returns under intercropping in coconut gardens. The experiment was designed as a 3 x 3 factorial experiment in a randomized block design (RBD) with nine treatments replicated thrice, involving various combinations of three spacings (60 cm x 60 cm, 75 cm x 75 cm, and 90 cm x 90 cm) and three sett sizes (100, 200, and 300 g). White yam canopy size increased with greater spacing. Regardless of spacings, higher sprouting per cent and vigorous sprouts were observed with 300 g setts. The length, girth, and weight of tubers was positively influenced by 90 cm x 90 cm spacing and these yield attributes were also positively favoured by 300 g setts. However, planting white yam setts of size 200 g at a spacing of 90 cm x 90 cm so as to accommodate 9000 plants ha–1 proved to be more advantageous due to production of optimum tuber yield (16.52 t ha–1), generation of additional employment (318 man days ha–1), higher net return (US $ 450.30 ha–1), and benefit:cost ratio (1.31).