Growth and biomass allocation of Jatropha curcas plants as influenced by nitrogen under different soil moisture regimes

Jatropha curcas plants were subjected to four levels of fertilization with nitrogen and four levels of plant available water in a 215-days long greenhouse experiment. The growth of jatropha plants was influenced by the supply of both water and nitrogen, but the effect of each of these factors was interdependent. Nitrogen fertilization favoured the growth of stem basal area, plant height and leaf area; however, these characteristics were influenced by water only when there was an adequate supply of nitrogen. The water use efficiency was increased when nitrogen was supplied and reduced when more water was supplied. The biomass allocation to leaves, stems and roots was also influenced.