Effect Of Nitrogen Management Research Articles

Effect of precision nitrogen-management and conservation tillage practices on growth, yield attributes and productivity of wheat (Triticum aestivum) in western Uttar Pradesh

A field experiment was conducted on sandy loam at Sardar Vallabhbhai Patel university of agriculture and technology, Meerut (Uttar Pradesh) during the winter (rabi) season of 2017–18, to study the effect of precision nitrogen management in wheat (Triticum aestivum L.) grown under conservation agriculture. The treatment comprising of tillage four crop establishment methods (T1 - Zero tillage (ZTW), T2 - Reduced tillage (RT), T3 - Furrow irrigation raised beds (FIRB), T4 - Conventional tillage (CTW)) in main plot and precision five nitrogen management (F1 – N 80:20 - N rate split as 80% basal and 20% at second irrigation, F2 - N 33:33:33 - N rate split as 33% basal, 33% at CRI stage (20–25 DAS) and 33% at second irrigation (40–45 DAS), F3 - N 80 – LCC - Split as 80% basal and further application of N based on LCC, F4 – N 50:50 - N rate split as 50% basal and 50% at CRI stage and F5 – FFP - farmers fertilization practice) in sub-plot and laid out in split-plot design with three replications. Results revealed that the maximum values of growth parameters (plant height, number of tiller, dry matter accumulation), yield attributes (number of spike, spike length, grain spike-1 and test weight) and yield was recorded in furrow irrigated raised beds system than rest of the tillage practices. Among precision nitrogen management treatments, the maximum values of growth characters (plant height, number of tiller and dry matter), yield attributes (number of spikes, spike length, grain spike-1 and test weight), grain and straw yield were noticed with application of fertilizer as N 80-LCC respectively. Thus, the use of furrow irrigated raised bed system along with application of nutrient as N 80 – LCC resulted the best combination for achieving higher growth, yield attributes and productivity of wheat crop.

Effect of nitrogen management on yield and quality of finger millet, Eleusine coracana (L) Gaertn

An experiment was conducted at agronomy farm of the Anand Agricultural University, Anand, Gujarat during kharif season of 2019 to study the effect of nitrogen management on yield and quality of finger millet [Eleusine Coracana (L) Gaertn]. Treatments comprised four different sources of organic manures viz FYM, vermicompost, NADEP compost and poultry manure used with combination of recommended dose of nitrogen as well as with or without Azosprillum as a seedling treatment. Number of fingers per earhead ranged from 6.35 to 8.40; finger length from 5.98 to 7.45 cm, grain yield from 1, 993 to 2, 677 kg/ha, straw yield from 6, 224 to 6, 749 kg/ha and test weight from 2.38 to 2.66 g. Application of 25 per cent N through vermicompost + Azosprillum + 50 per cent N through fertilizer resulted in higher value of yield attributes and grain and straw yield though this treatment was at par with some other treatments. Significantly higher nitrogen and protein content of finger millet grain was recorded under the same treatment which was at par with treatments 25 per cent N through FYM + Azosprillum + 50 per cent N through fertilizer and 25 per cent N through FYM + Azosprillum + 50 per cent N through fertilizer. Phosphorus, potash, iron, zinc, copper and manganese content in finger millet grain remained unaffected by different nitrogen management treatments.

Nitrogen and residue management effects on productivity and profitability of happy seeder wheat in Indian Punjab

Development of a suitable nitrogen (N) management strategy in wheat sown under residue retained conditions will go a long way in maintaining its sustainability. The reason for this is the variable concentration of N in rice residues and complexity of crop N demand. The present experiment was conducted at Punjab Agricultural University, Ludhiana during rabi2016–17 and 2017–18 to study the infuence of different residue and nitrogen management practices on productivity and proftability of Happy Seeder sown wheat. Experiment was conducted in randomized block design (RBD) consisting of eleven residue and N management treatments in four replications. The results revealed that yield attributes and grain yield of Happy Seeder sown wheat varied signifcantly with different residue and N management practices. Yield attributes (effective tillers, spike length & number of grains/spike) and grain yield (54.2 & 53.6 q/ha) were maximum in treatment where 150 kg N (30 kg at chopping of straw and 120 kg as per recommendation) was applied along with 5 t farmyard manure (FYM)/ha, which was signifcantly better than NC + N125, C + N125, C + FYM5 + N125 and C + N20+105 treatments but statistically at par with rest of the treatments. Highest gross (Rs. 1, 18, 155 & 1, 28, 011/ha) and net (Rs. 85, 120 & 94, 466/ha) returns were obtained with C + FYM5 + N30+120 during 2016–17 and 2017–18, respectively. But highest beneft cost ratio (2.59 & 2.87) was reported in treatment C + FYM5 + N30+95 during both years. It may be concluded that application of 20/30 kg N/ha at the time of chopping of straw improved grain yield of Happy Seeder wheat as compared to recommended schedule of N application.

Effect of integrated nitrogen management on soil properties and enzymatic activities

A field experiment was conducted at Agronomy farm, of S K N College of Agriculture, Jobner (Rajasthan) during kharif season 2017 in loamy sand soil with an objective “Effect of Integrated nitrogen management on soil properties in pearlmillet [Pennisetum glaucum (L.) R. Br. Emend Stuntz]”. The experiment was laid out in factorial randomized block design with three replications, comprised eight treatments of sources of nitrogen (Control, 50% RDN through urea+ 50% RDN through vermicompost, 50% RDN through urea+ 50% RDN through FYM, 75% RDN through urea+ 25% RDN through vermicompost, 75% RDN through urea+ 25% RDN through FYM, 100% RDN through urea, 100% RDN through vermicompost and 100% RDN through FYM) and two treatments of biofertilizer (without inoculation and with Azotobacter) were applied to the pearlmillet var. RHB-173. The application of sources of nitrogen,soil organic carbon, available nitrogen, phosphorus, potassium, dehydrogenase activity and alkaline phosphataseactivity were increased significantly with the application of 75% RDN through urea+ 25% RDN through vermicompost at flowering and harvest stage.The soil organic carbon, available N, P2O5, K2O, dehydrogenase activity and alkaline phosphates activities were also increased when inoculated with biofertilizer.

Effect of integrated nitrogen management through organic and inorganic sources on the yield of rice (Oryza sativa L.) and status of soil fertility at harvest

The present investigation was conducted with the objective of utilizing locally available organic resources for substituting chemical fertilizer nitrogen partly and augmenting soil health. The experiment was carried out for the crop kharif rice (Oryza sativa L.) in coastal Karnataka with eleven treatments laid out in randomized block design with three replications. Vermicompost (VC), Poultry manure (PM) and Fish manure (FM) were used as organic nitrogen sources integrated with mineral nitrogen source of fertilizer urea at substitution ratios of 25, 50 and 100 percent. These treatments were compared with control and recommended dose of nitrogen. The results revealed that the substitution of 50 per cent of nitrogen through VC recorded significantly (P<0.05) higher plant height (92.27 cm), higher number of productive tillers (16.85 hill-1), higher grain yield (5434 kg ha-1) and straw yield ( 6817 kg ha-1) compared to control. The results of the soil sample analysis for soil fertility parameters indicated that the major nutrients were significantly (P<0.05) influenced by integrated nitrogen management. The available nitrogen (382.36 kg ha-1) and available potassium (143.7 kg ha-1) were significantly (P<0.05) higher in the treatment T4 where a recommended dose of nitrogen was substituted by 50 percent VC compared to control (294.05 kg ha-1 and 92.31 kg ha-1 respectively). However, the available soil phosphorus was significantly higher with treatment 50 per cent RDN substituted by PM (78.83 kg ha-1) as compared to control (43.93 kg ha-1). Thus, integrated resource management improved crop yield and post-harvest soil fertility.

Effect of integrated nitrogen management and foliar spray of iron on groundnut yield, quality and economics in arid region

Aim: This experiment was conducted to find out appropriate technical intervention for integrated management of nitrogen and iron chlorosis in irrigated groundnut in arid regions. Methodology: Two levels of farmyard manure, five levels of nitrogen and three levels of iron spray were applied in irrigated groundnut. Chlorophyll content, active iron content, periodic dry matter accumulation, oil content and yield, protein content and nutrient uptake by groundnut were studied. Most effective level of farmyard manure, nitrogen application and iron spray were identified for optimum management of the resources.? Results: The results showed that application of farmyard manure @ 15 t ha-1, nitrogen @ 60 kg ha-1 in two or three splits and foliar spray of FeSO4 @ 1.0 % in combination with citric acid @ 0.1% was found supportive in correcting iron chlorosis by increasing chlorophyll and active iron content, improving oil content and yield, protein content and nutrient uptake and ultimately enhancing net return by groundnut under irrigated conditions. Interpretation: Farmyard manure, higher dose of nitrogen in split application and foliar spray of iron is helpful in correcting iron chlorosis, improving growth, quality and nutrient uptake and increasing income of groundnut growers under irrigated condition in arid regions.

Direct and residual effect of integrated nitrogen management on available macro nutrient status of soil under rice-maize cropping system

A field experiment was conducted at Agricultural college farm, Bapatla during 2018-19 and 2019-20 to find out the direct and residual effect of integrated nitrogen management on available nutrients under rice – maize cropping system in sandy clay loam soil. The results revealed an improvement in available N, P2O5, K2O with combined application of organics and inorganics over complete organic and control treatments. Application of 100% RDF recorded higher soil available N, P2O5 and K2O and it was on par with the treatments which received 50% N through inorganics + 50 % N through vermicompost or GLM respectively. Available N and P2O5 have shown significant difference with application of different nitrogen management treatments in kharif and different fertilizer doses in rabi. Available potassium was not significantly influenced by different treatments applied in kharif but significant differences were observed with application of different levels of N, P, K in rabi.

Effect of integrated nitrogen management on cane yield, juice quality and nutrient uptake of sugarcane ratoon crop

A field experiment was conducted in sugarcane ratoon crop at Sugarcane Research Station, Vuyyuru with an objective to study the effect of integrated management of nitrogen by substituting the recommended doses of nitrogen with organics such as neem cake, castor cake, vermicompost, azospirillum and green manures. Six treatments were replicated four times in randomized design. Variety tested was 99 V 30. The treatments include T1: 50% N through urea + 50% N through press mud cake + RDP & K, T2: 50% N through urea + 50% N through vermicompost + RDP & K, T3: 50% N through urea + 50% N through castor cake + RDP & K, T4­: 50% N through urea + Azospirillum @ 5kg/ha + 25% N through green manure + RDP & K, T5: 50% N through urea + 50% N through neem cake + 100% RDP & K and T6: 100% N through urea + RDP & K. Substitution of nitrogen up to 50% with organics rerecorded more yield compared to 100% recommended dose of nitrogen. Among the sources tried, castor cake resulted with highest shoot population at different stages of crop growth, cane yield, sugar yield and nutrient uptake by sugarcane ratoon crop followed by pressmud cake.

Effect of precision nitrogen management on yield and nitrogen use efficiency in different varieties of wheat (Triticum aestivum)

A field experiment was conducted during two consecutive winter (rabi) seasons of years 2015-16 and 2016-17 to study the effect of different nitrogen scheduling on yield and nitrogen use efficiency of different varieties of wheat (Triticum aestivum L.). The experiment was laid out in split-plot design with three replications; in which three varieties (viz. HUW 234, K 0307 and HD 2967) were planted in main plots. The combinations of 6 nitrogen scheduling practices which included different N application rates from 0 to 150 kg/ha in various split doses along with the use of LCC and Greenseeker was planned in sub plots. Results reveal that the yield attributing characters, grain yield, straw yield and biological yield were recorded significantly highest in HD 2967 as compared to other varieties. Whereas, varietal parameter did not significantly influence the agronomic efficiency, recovery efficiency and nitrogen harvest. Among nitrogen scheduling, application of 150 kg N/ha in three equal splits recorded significantly higher yield attributes, grain yield (4.70 and 4.81 t/ha), straw yield, biological yield, harvest index, and recovery efficiency of nitrogen. Greenseeker based nitrogen application recorded significantly highest agronomic efficiency and partial factor productivity of nitrogen.

Effect of tillage, residue and nitrogen management on soil physical properties, root growth and productivity of wheat (Triticum aestivum)

A study was conducted on a semi-arid climate and sandy loam soils of Indian Agricultural Research Institute farm, New Delhi to evaluate the short-term (5 years) interactions of tillage, residue and nitrogen management on soil physical properties, root growth and yield of wheat (Triticum aestivum L.) in a maize-wheat cropping system in a split-split plot design comprising two tillage (No tillage and conventional tillage), two residue levels (no residue, maize residue @ 5 t ha-1) and three nitrogen doses (N60, N120 and N180) as the main plot, sub plot and sub subplot treatments, respectively. It was observed that bulk density (up to 45 cm), penetration resistance (10-27 cm depth) reduced under no tillage and residue applied plots while the porosity (15-60 cm), mean weight diameter (0-15 cm), organic carbon (0-15 cm) improved in these treatments. The hydraulic conductivity was significantly enhanced due to residue applications in the surface layers (0-15cm). Root growth parameters were improved under no tillage and crop residue mulching. Although neither tillage nor residue mulching could significantly influence the grain and biomass yield of wheat on two years of study (2017-18, 2018-19), yield increased significantly with increasing nitrogen doses. Thus no tillage, residue mulching with 150% recommended dose of nitrogen can be practised for maintaining a better soil physical health, root growth without any significant reduction in crop productivity compared to conventional tillage.

Assessing Effects of Agronomic Nitrogen Management on Crop Nitrogen Use and Nitrogen Losses in the Western Canadian Prairies

Effective agronomic nitrogen management strategies ensure optimum productivity, reduce nitrogen losses, and enhance economic profitability and environmental quality. Farmers in western Canada make key decisions on formulation, rate, timing and placement of fertilizer nitrogen that are suitable for soils, weather, and farming operations within which they operate. Suitability of agronomic nitrogen management options are assessed by estimates from linear interpolations and extrapolations of temporally and spatially discrete field-plot measurements of nitrogen responses. Such estimates do not account for non-linear and offsetting biogeochemical feedbacks of nitrogen cycles and cannot provide comprehensive nitrogen budgets for alternative nitrogen management options. These limitations can be overcome by using process-based agro-ecosystem models that adequately simulate basic processes of nitrogen biogeochemical cycles and are rigorously tested against site observations. Ecosys is a process-based ecosystem model, which successfully simulated the biogeochemical feedbacks among nitrogen, carbon, and phosphorus cycles across different agro-ecosystems. This study deployed ecosys to generate spatially and temporally continuous estimates to assess crop nitrogen use and agronomic nitrogen losses from the crop fields across Alberta for alternative nitrogen fertilizer management scenarios. The study simulated effects of four nitrogen management scenarios: fall banded urea, fall banded ESN (Environmentally Smart Nitrogen), spring banded urea, and spring banded ESN on nitrogen recovery and losses from barley fields on mid-slope landforms. These simulations were done at township grids of ~10km x 10km over 2011-2015 utilizing provincial soil and climate datasets. Modelled annual N2O, N2 and NH3 emissions, and nitrogen losses in surface runoff and sub-surface discharge were lower by about 25%, 30%, 70%, and 40% respectively with spring banding than in fall banding across Alberta. Modelled barley yields and grain nitrogen uptake were similar in spring and fall banding indicating agro-economic and environmental sustainability advantage of spring banding in Alberta. These modelled estimates were consistent with estimates based on plot and laboratory research for Alberta and similar prairie conditions. This study pioneered a methodology of process-based agroecosystem modelling, which is replicable and scalable to assess cumulative impacts of alternative agronomic nitrogen management options on crop production and the environment on provincial, regional, federal, continental and global scales.

Effect of Site Specific Nitrogen Management on Seed Nitrogen—A Driving Factor of Winter Oilseed Rape (Brassica napus L.) Yield

It has been assumed that the management of both soil and fertilizer N in winter oilseed rape (WOSR) is crucial for N accumulation in seeds (Nse) and yield. This hypothesis was evaluated based on field experiments conducted in 2008/09, 2009/10, 2010/11 seasons, each year at two sites, differing in soil fertility, including indigenous N (Ni) supply. The experimental factors consisted of two N fertilizers: N and NS, and four Nf rates: 0, 80, 120, 160 kg ha−1. Yield, as governed by site × Nf rate interaction, responded linearly to Nse at harvest. The maximum Nse (Nsemax), as evaluated by N input (Nin = Ni + Nf) to WOSR at spring regrowth, varied from 95 to 153 kg ha−1, and determined 80% of yield variability. The basic reason of site diversity in Nsemax was Ni efficiency, ranging from 46% to 70%, respectively. The second cause of Nse variability was a shortage of N supply from + 9.5 soil to −8.8 kg ha−1 to the growing seeds during the seed filling period (SFP). This N pool supports the N concentration in seeds, resulting in both seed density and a seed weight increase, finally leading to a yield increase.

Residual effect of integrated nitrogen management and cropping systems on soil physical and physico-chemical properties

A field experiment was conducted to determine the residual effect of integrated nitrogen management and cropping systems on soil physical and physico-chemical properties during two consecutive years (2015-16 & 2016-17) on clayloam soils of Agricultural College Farm, Bapatla. The experiment was laid out in a two sample t-test for rice in kharif season with 2 treatments consists of M1 100% RDF, M2 (50% RDN+ 25% N through FYM + 25% N through neem cake + Azospirillum + PSB @ 2.5 kg ha-1(INM) and replicated thrice. During the immediate kharif, the experiment was laid out in a split plot design without disturbing the soil for succeeding rabi crops with the two treatments given to kharif rice as main plot treatments and each of these divided into five sub-plots of consisting of five crops as sub treatments by taking popular cultivars of rice (BPT 5204), blackgram (PU 31), maize (Sandhya), Sorghum (NSH-54), Sunflower (Shreshta) and mustard (Konark). Residual effect of integrated nitrogen management was non-significantly influenced all soil physical properties. Lowest bulk density, highest water holding capacity & porosity values, decreased pH values, improvement in soil organic carbon and CEC was found by Rice-blackgram cropping system followed by rice-sorghum and rice-maize.

Influence of different cropping systems and residual effect of INM on soil primary, secondary and micro nutrients

A field experiment was conducted to determine the residual effect of integrated nitrogen management and cropping systems on soil nutrient status during two consecutive years (2015-16 & 2016-17) on clay loam soils of Agricultural College Farm, Bapatla. The experiment was laid out in a two sample t-test for rice in kharif season with 2 treatments consists of M1 100% RDF, M2 (50% RDN+ 25% N through FYM + 25% N through neem cake + Azospirillum + PSB @ 2.5 kg ha-1 (INM) and replicated thrice. During the immediate kharif, the experiment was laid out in a split plot design without disturbing the soil for succeeding rabi crops with the two treatments given to kharif rice as main plot treatments and each of these divided into five sub-plots of consisting of five crops as sub treatments by taking popular cultivars of rice (BPT 5204), blackgram (PU 31), maize (Sandhya), Sorghum (NSH-54), Sunflower (Shreshta) and mustard (Konark). Results shown that the highest mean available N, P2O5, K2O, exch.Ca, exch. Mg, S, Fe, Mn, Zn and Cu were recorded in blackgram, which was on par with mustard followed by sorghum and sunflower sequence, which was superior over maize. The lowest values were observed in maize sub plot. Interaction effect of cropping system and residual effect of INM, significantly highest available nutrient values were observed with M2S1 treatment i.e. rice-blackgram cropping system in INM treated plots during both the years.

Effect of integrated nitrogen management on quality of rice

A field experiment was conducted during Kharif, 2012 at Rice Research Unit, Bapatla to study the quality of rice affected by integrated use of nitrogen. The experiment was laidout in Randomized Block Design with ten treatments. Results of the investigation revealed that significantly the highest quality parameters of rice like head rice recovery, volume expansion ratio, iron and zinc content were recorded by the application of 50 per cent nitrogen though organics and 50 per cent nitrogen through in-organics and it was on par with 100 per cent RDN through organic source treatment.

Effects of Irrigation and Nitrogen Management on the Growth and Nitrogen Concentration of Paddy Soil and Rice Plants

Effects of Irrigation and Nitrogen Management on the Growth and Nitrogen Concentration of Paddy Soil and Rice Plants

Effect of nitrogen management and seedling raising methods on the productivity of Aus rice under tidal ecosystem of Bangladesh

The low productivity of Aus rice in the tidal ecosystem of Bangladesh is mainly due to the difficulties in nitrogen (N) management under high tidal water along with unavailability of irrigation water during the onset of rice cultivation. Our present study demonstrated how the productivity of Aus rice could be improved using appropriate seedling raising methods and N management practices. The study was laid out in split plot design consisting two factors viz., seedling raising methods (wet seed bed and dry seed bed) and N management practices (six N treatments) in three replications. Results indicated that both the seedling raising methods and N management practices had significant effect on all the yield contributing characters of transplanted Aus rice under tidal condition. Specifically, the combination of seedlings raised in wet seed bed and fertilized with urea super granule (USG) at 10 days after transplanting (DAT) i.e., N3W showed the best values for plant height (110.33cm), number of effective tillers hill-1 (14.60), days required 50% flowering (53.00 DAT), days to maturity (84.33 DAT), panicle length (23.37 cm), number of filled grain panicle-1 (88.13), 1000-grain weight (43.17 g), grain yield (4.62 tha-1), straw yield (6.07 tha-1), biological yield (10.67 tha-1), and harvest index (43.17%). However, in considering the productivity/ grain yield, besides N3W, the whole urea application at land preparation along with wet seed bed (N1W) and USG application along with dry seed bed (N3D) also produced statistically similar results (p<0.01) and thus all these three combinations may be practiced for improving productivity and ensuring horizontal expansion of Aus rice in the tidal ecosystem of Bangladesh.

Grain-filling characteristics and yield differences of maize cultivars with contrasting nitrogen efficiencies

To investigate the effect of nitrogen management on the grain-filling characteristics and yield formation of maize cultivars with contrasting nitrogen efficiencies, and to identify differences in grain-filling characteristics and yield of maize cultivars in response to nitrogen management, a two-year field experiment was conducted in southwest China in 2015–2016. The grain-filling rate and duration of the N-inefficient cultivar XY 508 were higher than those of the N-efficient cultivar ZH 311. The 100-kernel weight of XY 508 was significantly higher than that of ZH 311. The kernel number per ear of ZH 311 was significantly higher than that of XY 508, making the population filling rate of ZH 311 significantly higher than that of XY 508. The higher population filling rate of the N-efficient maize cultivar led to a significant yield advantage over the N-inefficient maize cultivar. Nitrogen management effectively improved maize grain yield, but the response of maize cultivars with contrasting nitrogen efficiencies to nitrogen management was inconsistent. A basal fertilizer ratio 60.43% with a topdressing ratio 39.57% effectively increased grain-filling rate, delayed the time to maximum filling rate, prolonged the active filling period and effective grain-filling time, increased the 100-kernel weight, and maintained higher kernels per ear, thereby improving the population filling rate and maximizing the yield advantage of the N-efficient cultivar. A 100% basal fertilizer ratio not only increased the number of kernels per ear, but also maintained high grain filling characteristics to obtain a higher 100-kernel weight and increased the population filling rate, leading to a high grain yield in the N-inefficient cultivar. Thus, the 100% basal fertilizer ratio partially compensated for the deficient grain yield of the N-inefficient cultivar.

Tillage, Crop Residue and Nitrogen Management Effects on Nitrogen Uptake, Nitrogen Use Efficiency and Yield of Rice

Field experiment was conducted in three factorial strip split plot design to evaluate the effect of two establishment methods (EM) i.e. transplanted in puddled soil (Pu-TPR) and direct seeded in zero tillage (ZT-DSR), two residue levels i.e. residue kept at 3 t ha -1 (RK) and no residue (RR) with two nitrogen doses i.e. recommended dose (100 kg N ha -1) (RD) and farmers' dose (50 kg N ha-1) (FD) with six replications with individual plot size of 5.4 m × 6.3 m on rice variety Ram-Dhan during the year 2016. Nitrogen uptake, nitrogen use efficiencies and yield of rice were recorded. Straw nitrogen uptake was significantly higher in ZT-DSR than Pu-TPR. Similarly, grain straw and total nitrogen uptake were significantly higher in residue applied and recommended dose of nitrogen than no-residue applied and farmers-nitrogen dose treatments respectively. Nitrogen efficiency ratio and physiological efficiency index were significantly higher in Pu-TPR and no-residue applied treatments while partial factor productivity was higher in residue applied treatment. All nitrogen use efficiencies like partial factor productivity, nitrogen efficiency ratio and physiological efficiency index were significantly influenced by nitrogen dose and seen higher in recommended dose of nitrogen. Establishment methods had no significant effect on grain yield but straw yield was significantly higher in ZT-DSR but harvest index was seen higher in Pu-TPR. Grain yield and straw yield were significantly higher in residue applied treatment and recommended nitrogen but harvest index was higher in farmers-nitrogen dose.

Effect of irrigation and nitrogen management practices on productivity and nutrient uptake of direct-seeded rice (Oryza sativa)

An experiment was conducted at ICAR-Indian Agricultural Research Institute, New Delhi during kharif seasons of 2015 and 2016 to evaluate the effect of irrigation and nitrogen management on productivity and profitability in direct-seeded rice. Results showed that an increase in water stress from 20 kPa to 40/10 kPa resulted in the decline of grain yield over the years. Irrigation at 0 and 10 kPa recorded higher grain (4.8 and 4.7 t/ha, respectively) and net returns (45.2 and 46.2 ₹ × 103 /ha, respectively). Similarly, N uptake in grain and total was recorded higher with 0 kPa and 10 kPa, and reduced with increase in water stress at 40/10 kPa. In 2015 and 2016, split N application enhanced the grain yield (5.42 t/ha) than no N application (2.72 t/ha). Change in N application from three to four splits resulted in higher grain yield and net benefit as compared to no N application. Four N splits registered an increase of 6.67% in grain yield compared to three N splits. N splits registered an increase of N uptake in grain and total by 18.14 and 16.26 %, respectively than three N splits (68.9 and 131.2 kg/ha, respectively). Results implied that irrigation at 10 kPa with four N split increased the productivity and profitability of direct-seeded rice.