Vine cuttings for mini tubers production

Yams belong to the family of Dioscoreaceae and are members of the genus Dioscorea, which produces tubers and bulbils that are economically important (Ayensu, 1972). The yam occupies a significant place among the food crops produced in Côte-d'Ivoire. It is the first food crop with a production higher than 5, 5 million tons in 2011 (FAO, 2013)

The tubers of Dioscorea have a dual agricultural function: first, as source of food for millions of people and secondly, as planting material (Hahn, 1995; Craufurd et al., 2006). Thus, a considerable part of harvest is preserved like seed. According to Shiwachi et al. (2005), it is about 25 to 50% on average, the proportion of the harvest of yams reconverted in seed. Moreover, approximately 2 to 3 tons of the previous harvest may be used to plant a new crop on one hectare. Thus, the cost of the planting material increases the total production cost (Onwueme, 1978; Shiwachi et al., 2005). This cost of planting material occupies more than 33% of the total cost of production of the yam.

Considering this broad quantity of tubers or bulbils engaged as seed which could have been available for human consumption (Vander Zaag and Fox, 1981), other methods of yam propagation using vine cuttings have been developed (Njoku, 1963). Propagation using vine cuttings gives high rate of multiplication (20 50 %) without using tubers (Kikuno, 2009). The objectives of this study were, by using a carbonized rice husk as a media, to evaluate three planting modes and compare the response of some yam varieties vine cuttings to the applied planting modes.