Effect of calcium, magnesium and boron on nutrient uptake and yield of rice in Kole lands of Kerala

The Kole lands a unique wetland ecosystem of Kerala, is located 0.5–1.0m below mean sea level. An experiment was conducted in College of Horticulture, Vellanikkara, Kerala to study the influence of secondary and micronutrients viz. calcium, magnesium and boron on nutrient uptake and yield of rice in Kole lands. Six treatments including the soil test based nutrient application, package of practices recommendation (POPR) of Kerala Agricultural University for rice, combinations of the POPR with magnesium, calcium silicate, boron and absolute control were applied in the crop in a randomized block design with three replications. Higher uptake of nutrients especially primary and micronutrients were noticed by boron and calcium silicate application and lower uptake of Fe and Mn, thereby resulted in higher grain yields of 7.67 t/haand 7.18 t/ha respectivelyand straw yield was higher byapplication ofmagnesium. Correlation analysisrevealed that total uptake of boron, calcium and magnesium had positive and significant correlation with yield whereas negative correlation existed between Fe uptake and yield.