Biomass partitioning and morphological parameters of Trigonella foenum-graecum submitted to sulfur deficiency

In last decade several studies showed a serious reduction of sulfur content of agronomical crops associated to the decrease of the concentrations of sulfur in the atmosphere. This adverse situation would impact seriously the growth and the quality of numerous economically important plants like medicinal and aromatic species. Fenugreek (Trigonella foenum-graecum) is one of the most widely used aromatic and medicinal herbs in the world. The effect of sulfur deprivation in Fenugreek was investigated in plants grown on nutrient solution containing 1 mol m−3 S for control and 0.05 mol m−3 S for S-deficient plants. The experiment was conducted during 75 days after sowing. When compared to the control plants, the total sulfur and sulfate levels were lower in the leaves of S-deficient plants and total dry matter of the plant decreased by 32%. The most important reduction of biomass was recorded in the aerial part. The Chlorophyll content in leaves was reduced by 59% in S-deficient plants as compared to control. Partitioning of biomass and the plant morphology were also affected by S-deficiency. When compared to control, the leaf area and the LWR decreased by 37.7 and 35.3% respectively, but the LAR did not show any significant change. The leaves of S-deficient plants became thinner as result to the increase recorded in SLA value (+ 23.3%).