RESUMO
An ever-increasing population has issued an open challenge to the agricultural sector to provide enough food in a sustainable manner. The upsurge in chemical fertilizers to enhance food production had resulted in environmental problems. The objective of the current study is to assess the utilization of biostimulants for sustainable agricultural production as an alternative to chemical fertilization. For this purpose, two pot experiments were conducted to examine the response of radish against individual and combined applications of biostimulants. In the first experiment, the effects of chemical fertilizer (CK), glycine (G), lysine (L), aspartic acid (A), and vitamin B complex (V) were studied. The results demonstrated that V significantly improved the transpiration rate (81.79%), stomatal conductance (179.17%), fresh weight (478.31%), and moisture content (2.50%). In the second experiment, tested treatments included chemical fertilizer (CK), Isabion® (I), glycine + lysine + aspartic acid (GLA), moringa leaf extract + GLA (M1), 25% NPK + M1 (M2). The doses of biostimulants were 5g L-1 glycine, 1g L-1 lysine, 2g L-1 aspartic acid, and 10 ml L-1 moringa leaf extract. The photosynthetic rate improved significantly with GLA (327.01%), M1 (219.60%), and M2 (22.16%), while the transpiration rate was enhanced with GLA (53.14%) and M2 (17.86%) compared to the Ck. In addition, M1 increased the stomatal conductance (54.84%), internal CO2 concentration (0.83%), plant fresh weight (201.81%), and dry weight (101.46%) as compared to CK. This study concludes that biostimulants can effectively contribute to the sustainable cultivation of radish with better growth and yield.
RESUMO
Sugar industry produces a variety of organic byproducts causing disposal as well as environmental issues. This study investigated the safe use of these byproducts in assessment of soil physicochemical properties and metal accumulation in rice. A field experiment was performed with following treatments: control only NPK (CF), NPK + sugarcane bagasse (SB), NPK + press mud (PM), NPK + sugarcane vinasse (SV), NPK + SB + PM (SB + PM), NPK + SB + SV (SB + SV), NPK + PM + SV (PM + SV), NPK + SB + PM + SV (SB + PM + SV). Total byproduct input was (1.25 t ha-1) as recommended for organic inputs in the local area. The results indicated that integrated use of these amendments with chemical fertilization improved soil properties and rice yield. Organic matter was significantly improved in SB + SV (191.3%), SB + PM + SV (164.4%), and SB + PM (150.9%). Total N was significantly enhanced in SB + SV (193%), SB + PM + SV (166%), and SB + PM (152.5%); extractable P was high in SB (103%), PM + SV (89.7%), and SB + PM (51%); extractable K was significantly improved in PM (39.6%) and SB (33.4%); extractable Zn was significantly enhanced in SB (1172.8%), SV (829.2%) and PM (819.1%) in soil. Rice grain yield was significantly enhanced in SB (213.1%) and PM (208.8%) while combined application also improved the yield with reference to the CF. The application of SB + PM improved N (58.7%), P (27.4%), K (11.5%), and Zn (166.4%) concentration in grain, while metal accumulation was within the permissible limit. Zn concentration was significantly enhanced in SB + PM (166.4%) whereas the concentration of Cd and Pb was significantly reduced with the application of byproducts. Health assessment results showed no harmful effects for humans. Results conclude that these byproducts are good nutrients source and improve soil physicochemical properties without any health hazards.
