Effect of Decomposition of Various Organic Manures on No₃-N Content at Different Time of Interval

This incubation experiment was carried out at Department of Agricultural chemistry and soil science, AAU, Anand to investigate the effect of decomposition of different organic manures on No₃-N content at different time of interval. The experiment comprised of six treatments were: T₁: Control; T₂: FYM @10 t ha⁻¹; T₃: Poultry manure @ 2 t ha⁻¹; T₄: Neem cake @ 2 t ha⁻¹; T₅: Castor cake @ 2 t ha⁻¹ and T₆: Vermicompost @ 2 t ha⁻¹ with three replication. The results of incubation study showed that application of poultry manure @ 2 t ha⁻¹ (T₃) increased significantly the content of NO₃-N over all other treatments and this was at par with application of neem cake @ 2 t ha⁻¹ (T₄). Similarly, at 30 days after incubation the NO₃-N content ranged from 10.17 mg kg⁻¹ (control) to 39.63 mg kg⁻¹ (neem cake @ 2 t ha⁻¹). The highest NO₃-concentration was recorded under application of neem cake @ 2 t ha⁻¹ (T₄) over all the treatments and it was statistically at par with application of poultry manure @ 2 t ha⁻¹ (T₃). After 45, 60 and 75 days of incubation also the NO₃-N content varied in the same manner. The results of the present investigation clearly highlighted the fact that among all the organic manures poultry manure showed significantly better results because of its faster decomposition rate and lower C: N ratio comparatively other manures.