Response of two sesamum varieties (Kayamkulam-1 and Surya) to different plant densities and nitrogen levels

Abstract

An experiment was conducted at College of Agriculture, Vellayani during 1987 to study the influence of 3 plant densities (30 x 15 cm, 30 x 10 cm and 30 x 5 cm) and 4 levels of nitrogen (0,20,40 and 60 kg N/ha) on the growth, yield, oil and protein contents, chemical composition and nutrient uptake pattern of two sesamum vatieties (Kayamkulam -1 and Surya). The experiment was laid out in split-plot design with the variety-spacing combinations in the main plots and nitrogen levels in the subplots. The variety Surya recorded higher values for plant height, number of leaves/plant, leaf area index, drymater production, seed yield, stover yield, number of capsules/plant, capsule length, number of seeds/capsule, 1000 seed weight, harvest index, oil and protein contents of seeds, nitrogen and phosphorus contents and nitrogen, phosphorus and potassium uptake. Plant spacing of 10 cm resulted in maximum height. Number of leaves/plant, number of branches/plant, number of capsules/plant, number of seeds/capsule and harvest index were significantly reduced under close planting. Leaf area index, drymatter production, stover yield and the uptake of nutrients increased with close planting. Surya recorded significantly higher seed yield under 10 cm spacing. No significant differences was observed between 15 and 10 cm spacings with respect to seed yield of Kayamkulam -1 Spacing 0f 5 cm reduced the protein content of seeds. Close planting decreased the nitrogen, Phosphorus and potassium contents of plants. Plant height, number of leaves/plant, number of branches/plant, leaf area index, drymatter production, number of capsules/plant, number of seeds/capsule and stover yield increased upto 60 kg N/ha. Both the varieties recorded significantly higher seed yield with 60 kg N/ha. Capsule length and 1000 seed weight were increased only up to 20 and 40 kg N/ha respectively. Nitrogen application beyond 20 kg/ha increased the harvest index up to 60 kg/ha. Applied nitrogen significantly influenced the oil and protein contents of seeds up to 40 kg/ha. The uptake of all the nutrients and the nitrogen and phosphorus contents of plant were significantly influenced by applied nitrogen.