RESPONSE OF AGRONOMIC BIOFORTIFICATION WITH ZINC ON DUAL-PURPOSE OATS AND POST-HARVEST SOIL NUTRIENT STATUS IN ZINC DEFICIENT SOIL OF NORTHEASTERN REGION OF INDIA

Zinc is pivotal for normal metabolism in plants, animals and humans and its deficiency is generally known as hidden hunger.The North-eastern region of India with predominantly humid subtropical climate is deficient in zinc owing to acidic soil, presence of iron and aluminium oxides/ hydroxides and low organic matter content due to excessive rainfall and high temperatures.Hence, in order to evaluate the effect of agronomic biofortification of dual-purpose oats with zinc, a field experiment at the Instructional-cum-Research Farm (ICR Farm) of Assam Agricultural University (AAU), Jorhat, Assam was conducted during the rabi season of 2021-2022.The research was laid out in Randomized Block Design (RBD) with 12 treatments and three replications with the variety 'Kent'.Along with the recommended dose of fertilizers (RDF), different doses of zinc were applied as basal (5kg ha -1 , 7.5kg ha -1 and 10kg ha -1 ), foliar spray (0.5%, 0.75% at 30 and 75 days after sowing) and in combination of basal and foliar.The chemical analysis of green fodder, grain and straw showed significant improvement in nutrient content (nitrogen, potassium and zinc) and uptake (nitrogen, phosphorus, potassium and zinc) with the combined application of ZnSO 4 as basal at the rate of 7.5 kg ha -1 and foliar spray of 0.5% at 30 and 75 DAS along with RDF (T 11 ).Similarly, application of ZnSO 4 as basal at the rate of 7.5 kg ha -1 and foliar spray of 0.5% at 30 and 75 DAS along with RDF (T 11 ) improved the quality by significantly increasing the crude protein content and yield and reducing the crude fibre percentage.A fodder crop with higher crude protein to crude fibre ratio is considered superior due to its high digestibility and palatability.However, the post-harvest soil zinc content was significantly enhanced with the basal application of ZnSO 4 at the rate of 10kg ha -1 along with RDF (T 4 ) due to its direct availability.Hence, zinc fertilization is a promising tool in successful biofortification of grain and fodder as well as improving the zinc status in otherwise deficient soil for enriching micronutrient levels in soil-plantanimal-human continuum.