Effect of newly developed zinc chelates on productivity and quality of rice

Abstract

A field experiment was carried out with irrigated rice (Variety CO - 43) in red, non-calcareous, sandy loam soil (Typic Haplustalf). The soil was deficient in Zn and sufficient in all other micronutrients. The experiment was laid out in Randomized Block Design (RBD) with eight treatments viz., T1 - control (water spray), foliar application with different concentration of two versions of zinc chelates, Zn HEDP C and Zn HEDP L (T2 - T5), foliar application of 0.5% zinc sulphate (T6), soil application of ZnSO4 and ZnSO4 as enriched farm yard manure (FYM) (T7 and T8) respectively. Soil application of ZnSO4 at the rate of 25 kg ha−1 (T7) significantly increased the dry matter production, concentration and uptake of Zn in rice during different growth stages, followed by 0.3% spray of Zn HEDPL version (T5) and soil application of zinc enriched FYM (T8). Among foliar application of two versions of Zn chelates, the highest concentration and uptake of Zn was recorded with the foliar application of 0.3% Zn HEDP L. The treatment T7 registered significantly the highest grain yield of 6531 kg ha−1 followed by 0.3% Zn HEDP L (6313 kg ha−1) which was statistically on par with soil application of zinc enriched FYM (6308 kg ha−1). Quality parameters like starch content, amylose content, crude protein and true protein of rice grains as well as Zn concentration in the processed grains viz., brown rice, parboiled rice and milled rice increased markedly due to the treatment in T7 followed by T5 and T8 The findings indicated that soil application of zinc sulphate at the rate of 25 kg ha−1 along with recommended dose of NPK (150:50:50 kg ha−1) recorded the highest grain yield besides improving the nutritional quality of grains