Zinc Fertilization: Effects on Nutrients Availability and Productivity of Rice (Oryza sativa L.)

In India, zinc is considered as the fourth important yield limiting nutrient after nitrogen, phosphorus and potassium and it is essential for increasing crop production and enhancing animal and human health. To address these challenges, zinc fertilizations (basal & foliar) are practised for enhancing the soil health and crop productivity. The two years (2020-21 & 2021-22) on farm trial established at farmers field of district Saran, Bihar with the aim to compare the methods of zinc fertilization on plant available nutrients and crop productivity. An on farm trial was laid out in randomised block design involved seven replication of three different treatments viz., T1: NPK- 130:40:20 kg ha-1 (Farmer’s Practice), T2: RDF (NPK-120:60:40 kg ha-1 + Zn @ 5.0 kg ha-1 and T3: RDF (NPK-120:60:40 kg ha-1) + foliar spray of 0.5% ZnSO4 at 25 DAT. The pooled results of two years trial revealed that basal application of RDF-NPK and Zn (T2) significantly improved the soil organic carbon by 16.22%, plant available N by 11.96%, plant available P by 15.32%, plant available K by 10.99% and plant available Zn by 24.00% as compared to farmers practice. The crop productivity was also improved by 24.22% and 14.43% in treatment having basal application of Zn (T2) and foliar application of Zn (T3), respectively over farmers practice (T1). A positive polynomial relationship was obtained between soil organic carbon and plant available zinc due to soluble complexes form by zinc with soil organic matter. Thus, the basal fertilization method of zinc @ 5.0 kg ha-1 along with RDF-NPK is potentially recommended over foliar method and farmer practices to semi arid region of Bihar.