Abstract
Field experiments were conducted for two years (1997–1999) at the Central Institute of Medicinal and Aromatic Plants (CIMAP) in Lucknow, India, to study the influence of single and combined application of organic manure and inorganic fertilizers on growth and essential oil yield of Japanese mint (Mentha arvensis) in mint-mustard cropping sequence. In the original experiment, eight treatments comprising different combinations of manure (FYM) and fertilizer NPK (applied through urea, single superphosphate and muriate of potash, respectively) were compared. Attempts were also made to elucide the changes in soil organic carbon (C), soil microbial C, nitrogen (N), and phosphorus (P), and mineralizable C and N. This article deals with the influence of inorganic fertilizer [nitrogen–phosphorus–potassium (NPK)] and organic manure (FYM, mint distillation waste) on changes in soil organic C and microbial C, N, and P in mint-fallow-mustard cropping sequence. The data indicates that while inorganic NPK did not have any direct influence on soil microbial biomass, integrated nutrient supply, residue (distillation waste of mint) and type of cropping have been observed to have significant influence on build up of microbial biomass in soil.
Acknowledgments
The authors are thankful to the Director of CIMAP for providing necessary facilities during this investigation.