Effect of Organic Manures on Growth Performances and Nutritive Value of Pakchong Forage Genotype

Abstract

The study was conducted to determine the effects of sheep manure nitrogen and urea nitrogen on the growth parameters and nutrient composition of the Pakchong forage genotype. The experiment consisted of five treatments, namely T₀ = control (no fertilizer and manure nitrogen), T₁ = 100% urea nitrogen, T₂ = 66.67% urea nitrogen + 33.33% sheep manure nitrogen, T₃ = 66.67% sheep manure nitrogen + 33.33% urea nitrogen, and T₄ = 100% sheep manure nitrogen, with three replications for each treatment. The forage was harvested at two cutting periods, 60 and 90 days after planting (DAP). The effects of urea nitrogen and sheep manure nitrogen were significant for root length (p < 0.05) at 60 DAP. No significant (p > 0.05) differences were observed among the other growth parameters, such as plant height, leaf number, tiller number, leaf width, leaf length, stem diameter, and biomass yield at 60 DAP. Significant effects on stem diameter (p < 0.05) and tiller number (p < 0.01) were observed at 90 DAP. Significant variations in dry matter (DM) (p < 0.01), crude fiber (CF) (p < 0.01), and ash content (p < 0.05) were found at 60 DAP, with the highest values being 12.07%, 33.1%, and 16.55%, respectively. No significant (p > 0.05) effects were found on nutrient parameters such as DM, CF, crude protein (CP), ether extract (EE), and ash content at 90 DAP. The study further revealed that DM, CF, and ash contents increased with advancing plant age, whereas CP content decreased. The highest CF and DM contents were obtained at 60 DAP with the treatment combination of 66.67% sheep manure nitrogen and 33.33% urea nitrogen (T₃). The CP content of the genotype was 14.94% in T₂ and 11.86% in T₃ at 60 DAP and 90 DAP, respectively, although both values were lower than those obtained in T₁ at the corresponding cutting periods. For most of the agronomic growth parameters studied, the highest values were obtained with the treatment combination of 66.67% urea nitrogen and 33.33% sheep manure nitrogen (T₂). Under this treatment, DM, CF, and ash contents were 11.42%, 33.0%, and 16.15%, respectively.