Fertilizer perspective of biochar and compost derived from biomass of Parthenium hysterophorus in the rice wheat system in Punjab, Pakistan

Parthenium hysterophorus is an invasive weed, produces a lot of non edible biomass that is hazardous to humans. This study provides an insight to its beneficial use by converting the biomass into value-added materials like compost and biochar and subsequent amendment in soil as fertilizer. The biochar was prepared in a locally fabricated charcolator while the compost was prepared in a rolling tumbler. Two-year field experiment was set up using different combinations of biochar (BC), compost (C) and commercial fertilizer (CF) in the rice-wheat cultivation system in Lahore, Pakistan to assess soil health and crops performance after characterizing the products using advanced analyses. GCMS analysis has revealed the presence of stigmasterol and campesterol (plant growth promoters) in prepared compost. Field data showed that the combined application of compost and biochar in rice and wheat fields significantly improved the characteristics of soil like SOM and CEC. Agronomic characteristics such as the number of grains per tiller, grain weight and biological yield were significantly higher in C + CF (half dose of each) and almost equal to CF in the first year. In the second year, both crops agronomic performance was considerably more evident and pronounced following the same pattern. All other agronomic features also followed the same pattern. Thus, mixed application of organic and inorganic fertilizer on recurrent basis is recommended to improve yield of wheat and rice along with soil amelioration in the rice wheat cultivation system.