Optimization of Zinc Levels for Groundnut in Coastal Sandy Soil

Zinc deficiency associated reduction of yield is well known in coarse textured sandy soils. A pot experiment was carried out in the Department of Soil Science and Agricultural Chemistry, Annamalai University with groundnut var. VRI 2 during June-September 2006, to evaluate different levels of zinc on the yield and nutrients uptake by groundnut in coastal sandy soil. The experimental soil was sandy, taxonomically classified as Typic udipsaments with pH-8.39; EC-1.61 dS m^-1 and represented low status of organic carbon and zinc. The following treatments studied: T₁- NPK; T₂- NPK + ZnSO₄ @ 20 kg ha^-1; T₃- NPK + ZnSO₄ @ 25 kg ha^-1; T₄- NPK + ZnSO₄ @ 30 kg ha^-1 and T₅- NPK + ZnSO₄ @ 35 kg ha^-1. All the treatments received a common organic addition of composted coirpith @ 12.5 t ha^-1. The experiment was arranged in a Completely Randomized Design (CRD) with four replications. The experimental results revealed that, the application of NPK + ZnSO₄ @ 30 kg ha^-1 was significant in increasing the nutrients uptake and yield of groundnut. The percentage yield increase recorded with ZnSO₄ application @ 30 kg ha^-1 along with CCP was 15.25 percentage of pod and 15.81 percentage of haulm yield as compared to control.