OPTIMIZATION OF NITROGEN DOSE AND TIME OF APPLICATION FOR SEMI DRY RICE (Oryza sativa L.)
Loading...
Date
2018
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
PROFESSOR JAYASHANKAR TELANGANA STATE AGRICULTURAL UNIVERSITY
Abstract
A field experiment entitled “Optimization of nitrogen dose and time of application for semi dry rice (Oryza sativa L.)” was conducted during kharif, 2017 at Agricultural Research Institute, Professor Jayashankar Telangana State Agricultural University (PJTSAU), Rajendranagar, Hyderabad,. The soil of the experimental site was clay loam in texture, slightly alkaline in reaction, non saline, low in organic carbon and available nitrogen, high in available phosphorous and potassium. The experiment was laid out in randomized block design with 10 treatment replicated thrice.
The treatment were T1 – Farmers practice (120 kg ha-1 N at 3 splits with 12% at sowing , 44% at 40 DAS and 44% at 60 DAS), T2 - 120 kg ha-1 N in 4 equal splits of 25% each at sowing, 20, 40 and 60 DAS, T3 - 120 kg ha-1 N in 4 splits of 10% at sowing, 10% at 20 DAS, 40% at 40 DAS and 40% at 60 DAS, T4 – 120 kg ha-1 N in 4 splits of 20% at sowing, 20% at 20 DAS, 30% at 40DAS and 30% at 60 DAS, T5 – 140 kg ha-1 N in 4 equal splits of 25% each at sowing, 20, 40 and 60 DAS, T6 – 140 kg ha-1 N in 4 splits of 10% at sowing, 10% at 20 DAS, 40% at 40 DAS and 40% at 60 DAS, T7 – 140 kg ha-1 N in 4 splits of 20% at sowing, 20% at 20 DAS, 30% at 40 DAS and 30% at 60 DAS, T8- 160 kg ha-1 N in 4 equal splits of 25% each at sowing, 20, 40 and 60 DAS, T9- 160 kg ha-1 N in 4 splits of 10% at sowing, 10% at 20 DAS, 40% at 40
DAS and 40% at 60 DAS, T10- 160 kg ha-1 N in 4 splits of 20% at sowing, 20% at 20 DAS, 30% at 40 DAS and 30% at 60 DAS. A short duration variety Bathukamma was used as test variety.
Growth parameters like seedling vigour index, plant height, number of tillers m-2, dry matter production, leaf area index SPAD meter reading were highest with treatment T8-application of 160 kg N ha-1 25% each at sowing, 20 DAS, 40 DAS and 60 DAS compared to the other treatments. However, it was found to be on par with the treatments having 160 and 140 kg N ha-1 applied at various splits and T2 (application of 120 kg N ha-1 N in 4 equal splits at sowing, 20, 40 and 60 DAS). Crop growth was noticed to be lowest in the Farmer’s practice (T1- application with of nitrogen at 120 kg ha-1 N in 3 splits with 12% at sowing, 44% at 40 DAS and 44% at 60 DAS) at all the stages. Though statistically non significant, days taken for 50% flowering was found to be slightly delayed in the treatments with 160kg N ha-1 Yield attributes like number of panicle m-2, number of filled grains panicle-1, number of un filled grains panicle-1, total number of grains panicle -1 were found highest in the treatment T8-application of 160 kg N ha-1 25% each at sowing, 20 DAS, 40 DAS and 60 DAS compared to the other treatments but was found to be on par with the treatments having 160 and 140 kg N ha-1 applied at various splits and T2 (application of 120 kg N ha-1 N in 4 equal splits at sowing, 20, 40 and 60 DAS). Sterility index was also found to be high with higher doses of nitrogen.
Highest grain yield (4569 kg ha-1) and straw yield (5828 kg ha-1) were obtained with application of 160 kg N ha-1 25% each at sowing, 20 DAS, 40 DAS and 60 DAS compared to the other lower doses of treatments. This was found to be on par with application of the treatments having 160 and 140 kg N ha-1 applied at various splits and T2 (application of 120 kg N ha-1 N in 4 equal splits at sowing, 20, 40 and 60 DAS) . Lowest grain yield (3676 kg ha-1) and straw yield (4871 kg ha-1) were recorded with farmer’s practice. Increasing nitrogen level beyond a limit did not increase the harvest index and was not influenced by the time of application of nitrogen.
Highest nitrogen use efficiency (36.25% ) was recorded with application of 120 kg N ha-1 N in 4 equal splits of 25% each at sowing, 20, 40 and 60 DAS (T2) compared to higher dose of fertilizers. Highest net returns (₹ 38, 667 ha-1) was received from application of 160 kg N ha-1 in 4 equal splits of 25% each at sowing, 20, 40 and 60 DAS had given the compared to other treatments and was closely followed by the treatment T2 (120 kg N ha-1 in 4 equal splits of 25% each at sowing, 20, 40 and 60 DAS) with
₹ 38, 667 ha-1. Highest B:C (2.04) ratio was obtained from the treatment T2 application of 120 kg N ha-1 in 4 equal splits at sowing, 20, 40 and 60 DAS compared to other higher doses and schedules of application. Lowest B: C ratio (1.74) was noticed in farmer’s practice.
Description
Keywords
null
Citation
D10,265