Abstract

Jatropha curcas L. is a plant species from the family of Euphorbiaceae. The extraction of oil from its seeds produces a cake for which its accumulation causes different environmental problems related to solid waste management. The valorization of this cake into compost could be a contribution to solving this problem. Therefore different types of compost were made with J. curcas seed cake associated with animal feces incorporated at 0, 10 and 20% rate. To achieve their combination, 5 composting test and 2 replicates each have been set up. These composts were tested on cabbage yield in a completely randomized design with 6 treatments and 3 replicates. The different composts have improved significantly the chemical characteristics of the soil and the cabbage biomass yield. Mixing J. curcas seed cake with 10% sheep’s droppings (C₁₀) gave chemical characteristics compost with a high N and K content (Total-N 18.32 g.kg^-1; Total-K 17.60 g.kg^-1). The compost made with J. curcas seed cake and 20% sheep’s droppings (C₂₀) had the best cabbage total biomass and shoots of cabbage biomass yields respectively 43.11±3.15×10³ and 21.56±1.58×10³kg.ha^-1. That compost C₂₀ could be recommended to farmers for the improvement of crop yield field after trials followed by validation.

Key words: Jatropha curcas, seed cake, compost, cabbage shoot yield.