Field Experiments On Yams In Barbados 1965,-66

The yam (Dioscorea!l!1!) is a staple, low priced carbohydra te foodstruff in Barbados! and currently some 15,000 tons are produced annually as a c tach crop from land which is in preparation for sugar cane. An export trade has been started, which has considerable potential. Planting of yams has hitherto normally been at 5 ft. x 5 ft. (25 sq. ft. per plant), the snme as for sugar cane, but experiments in the 1965-66 season hllve clearly demonstrated that on a wide range of soils and under a 􀀀r􀀀a􀀀~􀀀g􀀀e of rainfall conditions, closer spacing would give higher yields per acre. In fact, no competition between plants could be detected until the territory per plant was reduced to 15 to 20 sq. ft.: at higher planting densities the yield per plant and the size of tubers was diminished (the smaller, better-shaped tubers resulting were more desirable for export), but the yield per acre increased within the, range of the experiment, i.e. 1,400 to 8,000 plants per acre. In commercial practice it appeared that anywhere in Barbados a density of about 3,500 plants per acre would be practicable for preparation land and would give substantially higher yields than are currently obtained. Comparisons of cuI tivars; showed that Puerto Rican Buck Yams, cuLtLva.r Barbados (from Trinidad) and Greneda Hunt all gave yields comparable with the commonly grown Crop Lisbon yams. Growth studies showed the general trend of development of the aerial parts and tubers; particularly notable was the very rapid z-ate of bulking of the tubers between the 26th and 36th weeks from planting - lending strong support to the planters' contention that yams should be planted in May.