Quality and yield of turmeric (Curcuma longa linn.) in response to mycorrhiza and nitrogen application

Abstract

Turmeric production is greatly hampered by dearth of knowledge of its agronomic requirements in Nigeria, particularly nitrogen requirement and possible enhancement of nutrient uptake by mycorrhiza. Hence, investigations aimed at examining the effect of nitrogen and the contribution of arbuscular mycorrhizal fungi on the yield and nutrient uptake of turmeric were conducted. It was a potted experiment with 5 levels of nitrogen (0, 45, 90, 135 and 180 kg N ha -1 ), and two levels of mycorrhiza (with and without). The experiment was arranged in a 5 × 2 factorial fitted into a completely randomized design with three replications. Data were obtained on the dry biomass yield, rhizome yield, curcumin content of the rhizome, nitrogen, phosphorus, calcium, magnesium and potassium uptake in the shoot. A repeat experiment was conducted using the best two treatments and the control in a 3 × 2 factorial experiment replicated thrice. All data were subjected to analysis of variance using SAS PROC. GLM and significant treatment means separated using LSD values. Applications of nitrogen and mycorrhiza independently and in combinations significantly enhanced the yield and curcumin content of turmeric. The rhizome yield in the mycorrhiza infested soil was not significantly different with the non application of mycorrhiza but there was an increase of approximately 15 % in the rhizome yield in the mycorrhiza infested soil. Application of 180 kg N ha -1 with mycorrhiza gave the highest biomass and rhizome yield and as such is the most suitable for turmeric production.