Micronutrients, though needed in smaller amounts, play a major role in the production and productivity of rice. Zn is the fourth most deficient nutrient element in Indian soils and its deficiency causes severe yield reduction in rice. Application of Zn either as foliar spray or soil application caused significant improvement in growth and yield attributes and yield of rice. Similar to that of Zn, B nutrition also caused significant improvement in growth and yield attributes and yield of rice. The review elaborates the effect of Zn and B nutrition on the growth, physiological parameters, yield attributes, yield and quality of rice.

The experiment was conducted at Coconut Research Station, Balaramapuram with an objective to study the effect of nutrient levels and nutrient schedules on physiological parameters and grain yield of upland rice (MO 21-Prathyasa rice variety) intercropped in coconut. Field experiment was conducted in factorial randomized block design with nutrient levels as first factor and nutrient schedules as second factor in three replications. Nutrient levels had significant effect on the physiological parameters. Among the nutrient levels rested, NPK applied @ 120:30:60 recorded higher total chlorophyll (2.803 mg g recorded the highest grain yield and it was followed by NPK applied @ 70:30:35 kg ha -1 . Among the nutrient schedules, N applied as three equal splits, P as basal and K in two equal splits along with foliar spray of zinc sulphate 0.2 per cent and sodium borate 0.04 per cent at 45 DAS recorded the highest grain yield (3.25 t ha -1 ). The study clearly revealed that excessive vegetative growth is not a desirable parameter for higher grain yield.

Abstract:Field experiment was conducted at Coconut Research Balaramapuram, during Kharif 2017 to study the effect of nutrient levels and schedule of application on the quality parameters of upland rice intercropped in coconut. The experiment was conducted in randomized block design (RBD) with four different nutrient levels and four different schedules of nutrient application. Quality parameters like crude protein and starch content were significantly influenced by nutrient levels. The crude protein content was found to increase with increase in N level, however starch content was found to increase up to 70 kg N and 35 kg K ha -1 and after that a decline in trend was observed. The highest crude protein content (8.38 per cent) was recorded with highest nutrient level, NPK @ 120:30:60 kg ha -1 . However, lower nutrient level, NPK @ 70:30:35 kg ha -1 recorded higher starch content (85.03 per cent). Among the schedule of nutrient application, N applied in three equal splits (15 days after sowing (DAS), active tillering and panicle initiation stage), P as basal and K in two equal splits (15 DAS and panicle initiation stage) along with foliar application of 0.2 per cent zinc sulphate and 0.04 per cent sodium borate at 45 DAS recorded the highest crude protein (7.50 per cent) and starch content (84.17 per cent). The study clearly indicated that the increased level of N and K increased the protein content due to the active role of N and K in protein synthesis. However, high rate of N application decreased the starch content. In addition to the application of NPK, foliar nutrition of zinc sulphate and sodium borate at 45 DAS considerably improved the quality of grain by increasing the starch and protein content.