Integrated Nutrient Management in Banana

Abstract

Sindh is the major banana growing province contributing 85% of the total banana area and production in Pakistan. Under low soil fertility and organic matter content, banana yields are low by any standard. This study evaluated the effect of organic amendments (no amendment, FYM and CPM, each at 20 t ha-1) and mineral fertilizer treatments (N, NP0.5, NP0.75, NP1.0, 1.25 NP) based on the N-P2O5-K2O rates of 500-250-500 kg ha-1. Results of this study depicted that plant growth i.e. plant girth and number of leaves plant-1 increased significantly with application of organic amendments as well as with mineral fertilizers. Similarly, both the mineral fertilizers and organic amendments were effective in significantly improving banana yield and yield parameters. Application of organic amendments produced, on an average, 19.4% increase in bunch weight, 7.7% in bunch length, 15.7% in finger length, 8.1% in finger girth, 13.1% in number of fingers bunch-1, 11.1% in number of hands bunch-1 and 22.6% in banana yield compared to the treatments not receiving any organic amendment. The FYM and CPM were equally effective in improving yield and yield parameters with slightly higher values for FYM in most cases. When applied alone, organic amendments increased banana yield by 19% over N alone treatment. In case of fertilizer application, the yield and yield contributing parameters increased with the rate of NP and further with K application, maximum yield obtained with NPK alone treatment was nearly equal to that obtained with the organic amendments alone. Under combined use of organic amendments and mineral fertilizers, highest values were obtained for almost all the yield parameters and yield. Expressed on percentage basis, banana yield increased by 59.4% with application of NPK plus FYM as compared to N alone treatment and 36.4% when compared with NPK treatment. There was no additional benefit in application of 25% more than the recommended NP (1.25 NP). Application of organic amendments significantly improved the leaf tissue NPK and micronutrient contents which remained above the critical limits of 2.6, 0.22 and 3.0 % for NPK, and 9, 80, 25 and 18 mg kg-1, for Cu, Fe, Mn, Zn. Fertilizer application also improved leaf nutrient contents except where either no or low rates of P and K were applied. Among the micronutrients, Zn was the only nutrient which was below the critical limit in the treatments not receiving any organic amendment. Nutrient composition of banana fruit also improved significantly with the application of organic amendments while increasing fertilizer rates resulted in decline in micronutrient contents. The levels of Cu, Fe, and Mn were still adequate though for optimal crop nutrition while Zn contents were below optimal levels unless organic amendments were applied. Soil properties after completion of one production cycle showed significant build up with the addition of FYM and CPM in organic matter (0.59 to 1.01%) and available nutrients i.e. P (12.1 to 24.7 mg kg-1), Cu (2.02 to 3.51 mg kg-1), Fe (8.9 to 23.3 mg kg-1), Mn (8.5 to 10.5 mg kg-1), and Zn (0.61 to 1.18 mg kg-1). Overall, integrated use of NPK and FYM outperformed all other treatments and produced maximum monetary benefit.