Application of different levels of NPK along with soil and foliar application of zinc and boron in cashew for increasing production with sustainability

Abstract

The effect of different levels of nitrogen, phosphorus and potassium along with soil and foliar application of zinc and boron on yield and quality of cashew nut (Annacardium occidentale L.) Variety Vengurla-4 in lateritic soil of Konkan has been studied during May 2016 to April 2017 in Randomized Block Design with four levels of NPK (1.0:0.25:0.25, 1.0:0.50:0.50, 1.5:0.75:0.75 and 2.0:1.0:1.0 kg NPK per tree) with or without soil application of boron through borax @ 50g + zinc through zinc sulphate @ 125g/tree or foliar application of boron through borax @ 0.25% + zinc through zinc sulphate @ 0.5% /tree, an absolute control (to judge the fate of native nutrients) comprising thirteen treatments replicated thrice. It is revealed from the study that 12.80 to 44.09 per cent increase in the yield of cashew nut was recorded during 2016-17 with application of different levels of nitrogen, phosphorus and potassium along with soil or foliar application of boron through borax and zinc through zinc sulphate. The highest yield of cashew nut per tree (10.36 kg tree-1) and number of nuts per kg were was recorded with the application of recommended dose of fertilizer + soil application of boron through borax @ 50 g + zinc through zinc sulphate @ 125g/tree (treatment T6). Application of 2.0:1.0:1.0 NPK kg/ tree + boron through borax @0.25%+ zinc through zinc sulphate @ 0.5%/tree (T13) recorded significantly higher organic carbon and available Mn in the soil. Application of fertilizer levels @1.0:0.25:0.25 NPK kg/tree + boron through borax @ 0.25%+ zinc through zinc sulphate @0.5%/tree (T10) recorded significantly higher available nitrogen and zinc in the soil. All these treatments were at par with the application 1.0:0.50:0.50 kg NPK per tree along with spraying of foliar application of boron though borax @ 0.25% + zinc through zinc sulphate @ 0.5% (T11). By considering the higher yield of cashew nut, chemical properties of soil and availability of nutrients in the soil, application 1.0:0.50:0.50 kg NPK per tree along with spraying of foliar application of boron though borax @ 0.25% + zinc through zinc sulphate @ 0.5% found to be beneficial in lateritic soils of Konkan.