Improving the performance of a traditional variety of yam produced under ferralsol poor in organic matter in the forest areas of Cote d'Ivoire

<p>A study on the potential of three previous cropping of ferralsol was conducted in the forest zone of Cote d'Ivoire<br>from 1999 to 2000. These parcels were a fallow of Chromolaena odorata, a previous yam and a previous cassava.<br>The aim of this study was to know the soil fertility and to assess the effect on the productivity of the local variety<br>called “bete bete”, a water yam very widespread. Thus, two micro doses of NPK compared to a control without<br>fertilizer was made for an objective of 30 t/ha. This work was carried out according to the pattern blocks of Fisher<br>with six replications. It was obtained in 1999 under fallow the highest yield (22.4 t/ha) for T1 (24N 48P 36 K)<br>against 18.4 t/ha and 14.4 t/ha respectively, yam and cassava subplot. In 2000, it was obtained under fallow 23.1<br>t/ha for T1 against 22 t/ha for T2 (70N 48P 36K). The lowest yield (12 t/ha) was obtained by T0 under cassava.<br>The difference was significant between T0 and T1 and between T2 and T0 in 1999 and 2000 under previous<br>fallow and previous yam. But, between T1 and T2, there was no significant difference. As cons, under previous<br>cassava, there was no significant difference between treatments. The results showed that the fertilizer had an<br>effect on bete bete yield. The conditions of cropping yam were more suitable under fallow than land previously<br>cultivated but need manure to increase highly the yield.