Effect of Organic and Inorganic Fertilization on Soil Enzyme Activities in Relation to Yield and Proximate Composition of Colocasia (Colocasia esculenta L) in Alfisols of Eastern India

ABSTRACT

Field experiments were conducted for two kharif seasons during 2018–2020 to study the effect of inorganic fertilizers and organic manure on soil quality, yield, and proximate composition of colocasia (Colocasia esculenta L) in an Alfisol. Significantly highest mean cormel yield of colocasia (24.27 t ha⁻¹) was recorded due to integrated application of 10.0 t ha⁻¹ farmyard manure (FYM) combined with ½ NPK fertilizers. Application of 40, 80, and 120 kg ha⁻¹ of potash (K₂O) registered a mean yield response of 41, 56, and 63% over control, respectively. The biochemical constituents (starch, total sugars, and dry matter) in the cormels of colocasia were found to be higher (12.92, 1.26 and 24.67%, respectively) due to balanced application of 80–30-80 kg ha⁻¹ of N, P₂O₅, and K₂O at par with FYM+½NPK. Integrated application of FYM+½NPK has recorded higher total counts of fungi (57x10⁴ cells g⁻¹) and actinomycetes (53x10⁵ cells g⁻¹) and showed a significant relationship with yield (r = 0.90** and 0.87**, respectively). Higher soil enzyme activities with respect to dehydrogenase (DHA) (1.582 µg TPF hr⁻¹ g⁻¹), fluorescein diacetate hydrolysis assay (FDA) (2.356 µg g⁻¹ hr⁻¹), urease (303.2 µg NH₄-N g⁻¹ hr⁻¹), acid phosphatase (69.36 µg PNP g⁻¹ h⁻¹), and alkaline phosphatase (49.76 µg PNP g⁻¹ h⁻¹) were observed due to conjoint application of FYM+½NPK. Fungi had a highly significant relationship with DHA, FDA, and urease activities (r = 0.87**, 0.85**, and 0.84**, respectively), whereas actinomycetes showed a significant relationship with acid and alkaline phosphatase activities (r = 0.88** and 0.93**, respectively). Applications of organic manure combined with ½NPK not only sustained the soil quality but also enhanced the productivity of colocasia.

KEYWORDS:

• Inorganic fertilizers
• organic manure
• colocasia
• yield
• biochemical constituents
• soil enzyme activities

Disclosure statement

No potential conflict of interest was reported by the author(s).