Effect of Arbuscular Mycorrhizal Fungi and NPK Fertilizer on Roots Growth and Nitrate Reductase Activity of Coconut

摘要

Background and Objective: A good seeds characteristics of coconut are expected to have optimal root and shoot growth which can be affected by mycorrhizal inoculation. This study aimed to determine the effect of arbuscular mycorrhizal fungi (AMF) and NPK fertilizer doses to colonization, roots and shoots growth, physiological parameters (Nitrate Reductase Activity) (NRA) and chlorophyll on early growth of coconut. Materials and Methods: Coconut seedlings were transplanted in the field in polybags and treated with a dose of treatment. The first treatment was the application of NPK fertilizer doses (4 and 6 g/seeds and without NPK). The second treatment was the application of AMF inoculum doses (4 and 2 g/seeds and without AMF). The parameters of colonization, chlorophyll contents, roots dry weight, total root length, root surface area, root diameter, number of primary roots, fresh weight of root, stem and leaf were evaluated using analysis of variance based on 3×3 factorials completely randomized design followed by Duncan’s multiple range test with p0.01 as the post hoc . Results: The combination of AMF application doses of 2/seeds with NPK fertilizer application doses of 4 g/seeds significantly increased (p0.01) the highest colonization by reaching 41.60% compared with control. The application of AMF doses without NPK fertilizer treatment significantly increased (p0.01) NRA and root surface area. The AMF application (2-4 g/seeds) combined with NPK fertilizer treatment (6 g/seeds) significantly increased (p0.05) the root surface area compared with control. Conclusion: The AMF application combined with NPK fertilizer increased colonization, NRA and root surface area.