Effect of planting distance of <i>in vitro</i> plants on <i>Dioscorea rotundata</i> Point cv. `White Guinea' minituber production in greenhouse

Abstract

Considering the limited availability of planting material in yam cv. `White Guinea' (Dioscorea rotundata Point), mainly due to the tubers that are consumed are used as seed, have been developed methods for its micropropagation. However, field survival of the plants is very low, so the search of alternatives, among then, the production of minitubers, are necessaries. This work aimed to determine the effect of planting distance of the in vitro plants in green house on minitubers production. Four planting distances of in vitro plants (0.05x0.05 m, 0.10x0.10 m, 0.15x0.15 m, 0.20x0.20 m) were studied. In each treatment was determined: number of minitubers, fresh mass of tubers per plant and its category as planting material. The highest values of number of tubers per plant (3.83 and 3.12) were obtained with the distance x 0.10 0.10 x 0.15 m and 0.15 m, respectively. With the planting distance of 0.10 x 0.10m, the higher numbers of minitubers per square meter were achieved: 100, 110 and 90 in the categories with a fresh mass between 16.0 to 25.9 g, 26.0 to 35.9 g, 36.0 to 50.0 g (26.10%, 28.72% and 23.49%, respectively). These results, obtained for the first time in this crop, confirm the usefulness of minitubers production in greenhouse from in vitro plants of yam as an alternative to obtain planting material. Keywords: greenhouses, seed, tuber, yams