Abstract:
Pot culture experiments were conducted to examine the best combination of poultry manure and chemical
fertilizer as sources of phosphorus and sulphur on the microbial activity in a soil after sequential cropping
system where main and residual crops were groundnut and sunflower respectively. To supply equal basis
of phosphorus at 34 kg PzOs ha-1 and sulphur at 75 kg S ha'1 following treatments were used: L00o/o PM
(Poultry Manurel, 750/o PM and 25o/o CF (Chemical Fertilizerl, 50% PM and 50% CF,25o/o PM and 750/o CF
and 100% CF. Six treatments, including a no-P and S as control were replicated three times in a completell.'
randomized design. After each crop soil was taken to estimate the microbial activity. In the main crop, the
combination of 75 o/o PM and 25 o/o CF enhanced microbial population and biomass carbon content and
was comparable with 500/o PM and 50 %o CF treatment. The soil organic carbon content was higher in sole
poultry manure treatment. Same trend was observed in soil after residual crop also.
