Effect of varied planting geometry, genotypes and seed rate on yield, nutrient uptake and post-harvest soil available nutrients status in browntop millet under Alfisols of Northern Karnataka

Abstract

Browntop millet is an annual warm-season grass majorly cultivated for its grain and fodder in the dryland regions. The standard package of practice for this crop is still under infant stage as the production practices are specific to varied agroclimatic conditions and changing climatic scenario. Hence, a field experiment was conducted at ICAR-KVK, Hanumanamatti, Haveri, Karnataka, India during Kharif 2020. The experiment was laid out in split-split plot design and replicated thrice. Main plot composed of three planting geometries (30, 45 and 60 cm row spacing), sub plot comprised of two genotypes (IIMR Y II and Dharwad local) and sub-sub plots comprised of three seed rates (5, 7.5 and 10 kg ha-1). Results revealed that browntop millet spaced at 45 cm row spacing recorded significantly higher grain yield (624 kg ha-1), nutrient uptake (25.39, 8.39 and 20.00 kg N, P and K ha-1, respectively) and partial factor productivity of NPK and surpassed 30 and 60 cm row spaced treatments. Between the two genotypes, no significant difference was observed with respect to any of the observations recorded. The seed rate of 7.5 kg ha-1 found to be optimum as reflected in significantly higher grain yield (585 kg ha-1), nutrient uptake (26.32, 8.33 and 19.47 kg N, P and K ha-1, respectively) and partial factor productivity of NPK. The treatments that recorded significantly lesser yield and have uptaken lesser nutrients reflected higher soil nutrients post-harvest of the crop. The interaction effect of all the three factors found to be non-significant with respect to all the observed parameters. Hence, it is recommended to adopt 45 cm row spacing and 7.5 kg ha-1 seed rate using either Dharwad local or IIMR YII genotypes for higher grain yield and nutrient use efficiency.