Agricultural Research Management Information System

Home
Research Summary
Search
About Us
- ARMIS
- Brochure
Contact Us
Report
User Request
Data Input
Help
- Operation Manual
  - PDF
  - Video
- Program Area & Commodity
We have reached 37600 number of research entries at this moment.

- Logout

Research Detail

Home
Research
Detail

Chlorophyll Meter-based Dynamic Nitrogen Management in Wheat (triticum Astivum L.) Under Subtropical Environment

Md Nazmul Hasan
Department of Agronomy, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur-1706, Bangladesh.

Qazi Abdul Khaliq
Department of Agronomy, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur-1706, Bangladesh.

Md Abdul Baset Mia
Department of Crop Botany, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur-1706, Bangladesh.

Md Nasimul Bari
Department of Agronomy, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur-1706, Bangladesh.

Md Rafiqul Islam
Department of Agronomy, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur-1706, Bangladesh.

Abstract/ Executive Summary:

Injudicious use of nitrogen fertilizer is very commonly practice in tropical and subtropical regions. SPAD (Soil-Plant Analysis Development) chlorophyll meter-based nitrogen top-dressing may reduce the risk of under or over application. Considering this, the study was conducted to measure the relative advantage of dynamic methods of nitrogen fertilization over conventional method in wheat field. For this, conventional nitrogen (CN) treatments i.e. CN₆₀, CN₉₀, CN₁₂₀, CN₁₅₀ at 60, 90, 120 and 150 kg ha^-1 were compared with four chlorophyll meter-based dynamic nitrogen (DN) treatments i.e. DN₈₀, DN₉₀, DN₁₂₀, DN₁₀₀at 80, 90, 120 and 100 kg ha^-1 nitrogen. Irrespective of treatments, SPAD meter readings remained above 45 (threshold value) beyond 50 days after seeding, but plant performance varied depending on the methods and doses used in nitrogen top-dressing. Treatment CN₁₅₀ performed better displaying the highest SPAD values, total dry matter production, leaf area index, crop growth rate and net assimilation rate resulting to the highest grain yield (5.10 t/ha) in wheat. The plant performance in DN₁₂₀, DN₁₀₀, DN₉₀and CN₁₂₀treatments were statistically similar to that of CN₁₅₀in respect of all most all plant characters studied. Comparing with CN treatments, DN treatments resulted in better plant growth and grain yield at the same level of nitrogen fertilizer. This is because of maintaining need-based fertilizer at early stage of wheat and application of appropriate amount of nitrogen fertilizer in each time in DN treatments compared to CN treatments. The result suggests that chlorophyll meter can be effectively used for real time nitrogen top-dressing to increase productivity of wheat.

Keywords: SPAD; Chlorophyll meter; Nitrogen; Top-dressing; Wheat

Location: Field Research Site of the Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur

Start Date: 00-12-2012

End Date: 00-03-2013

Program Area: Crop-Soil-Water Management

Commodity: Wheat

Objectives:

To measure the relative advantage of dynamic methods of nitrogen fertilization over conventional method in wheat field.

Methodology:

The experiment was conducted at the Field Research Site of the Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur-1706 from December, 2012 to March, 2013. This region is characterized by a subtropical climate having hot summer (May-August) and mild winter (December-February). It belongs to Agro Ecological Zone 28 at geographic coordinates 24⁰05¢ N latitude and 90⁰16¢ E longitude with an elevation of 8.4 m above the mean sea level. The crop tested in the experiment was widely cultivated wheat variety BARI Gom-27 in Bangladesh. The experiment was laid out in a Randomized Complete Block Design with four replications. The unit plot size was 3×2 m. There were eight treatments of which four were conventional nitrogen (CN) management viz. (1) CN₆₀= 60 kg ha^-1 N (2) CN₉₀= 90 kg ha^-1 N (3) CN₁₂₀= 120 kg ha^-1 N and (4) CN₁₅₀= 150 kg ha^-1 N and four were dynamic nitrogen (DN) management: viz. (1) DN₈₀= 20 kg ha^-1 N in each time started from 18 days after sowing (DAS) and for four times total amount was 80 kg ha^-1 N, (2) DN₉₀= 30 kg N ha^-1 in each time started from 19 DAS and for three times total amount was 90 kg ha^-1 N, (3) DN₁₂₀= 40 kg N ha^-1 in each time started from 20 DAS and for three times total amount was 120 kg ha^-1 N and (4) DN₁₀₀ = 50 kg N ha^-1 in each time started from 24 DAS and for two times total amount was 100 kg ha^-1 N. In CN treatments, one third of nitrogen was applied as basal application and the rest of the nitrogen was applied at 25 and 50 days after sowing (DAS) as top dress. In DN, supplied N application was done when the SPAD value fell down the critical value of 45 as suggested by Barraclough and Kyte. Seeds were placed continuously in lines by making narrow and shallow furrows with iron tine and covered properly. The crop was terminally harvested around four months after sowing. The data refer to growth and physiological parameters as well as yield and yield attributes. Among the physiological parameters, SPAD value over time and corresponding leaf chlorophyll content, dry matter production, leaf area index, crop growth rate and net assimilation rate were recorded. The yield data viz. 1000-seed weight, the number of tillers per m², spike length, the number of spikelet per spike and the number of grains per spike and the grain yield were recorded when the plant attained full maturity. Twelve wheat plants were selected randomly from each plot at 17 DAS excluding border area and SPAD value was taken from middle portion of the latest fully developed leaf by using Minolta chlorophyll meter (Model: SPAD-502, Minolta Co. Ltd., Japan). Thus SPAD values were taken from each plot at 3 days interval up to 84 DAS. Collected data were subjected to statistical analysis. Arithmetic mean values of the different plots, those experiencing conventional and dynamic nitrogen supplements were compared to evaluate the difference in the plant performance by employing Least significance difference (LSD). MSTAT-C and SPSS program were used to perform statistical analysis.

Source of Information: Curr Agri Res 2016; 4(1), ISSN: 2347-4688, Online ISSN: 2321–9971

Article Link (Online Journal): http://www.agriculturejournal.org/?p=1804

Funding Source:

Budget:

Total Budget (Tk.) :

Achievement/Findings:

From the study, it revealed that SPAD chlorophyll meter helps to quantify leaf greenness in wheat. Thus meter values should be maintained 45 at early stages, and appropriate amount of N fertilizer should be top-dressed to facilitate growth and development towards higher grain production. It also affirms that chlorophyll meter-based N management saved significant amount of nitrogen without significant yield loss. Therefore, SPAD chlorophyll meter can be a useful tool to the farmers of subtropical region for maintaining judicious use of N fertilizer and sustainability of growing wheat.

Knowledge Management: Journal