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

Determination of Crop Coefficient for Rice-2006

Dr M A Rashid
CSO and Head
Irrigation and Water Management Division, BRRI, Gazipur-1701, Bangladesh

Abstract/ Executive Summary:

A field experiment was conducted to determine kc value for rice. Mini lysemeter was installed to determine vater balance. ET Rates were measured in all seasons. In Aus season, the mean daily evapotranspiration (ET) rates as measured in rice field by closed bottom lysimeters was 4.50 mm/day, for the season. Similarly in T. Aman season, the mean daily ET rates was 4.23 mm/day for the season. In Boro season, the mean daily ET rates was 4.6 mm/day for the whole growing season. There were little variations in ET rates among the varieties. The ET rates showed a gradual increase as the crop growing season progressed. In Aus season, the Kc values ranged from 1.12 to 1.17. The highest value was obtained from BRRI dhan39 and the lowest from BR 3. There was no wide variation in Kc values among the varieties. In T. Aman season, these values ranged from 1.03 to 1.07. In this season the difference in Kc values for different varieties was negligible. Similarly in Boro season it varies from 1.14 to 1.19.The results of three seasonal field experiments showed that there were slight variations in Kc values from season to season but the difference among the varieties were negligible. The Kc values in Boro season were slightly higher than those of Aus and T Aman seasons

Keywords: Kc value, Crop coefficient, Evapo transpirasion

Location: BRRI farm, Gazipur

Start Date: 01-07-2005

End Date: 30-06-2006

Program Area: Crop-Soil-Water Management

Commodity: Water management

Objectives:

To determine the crop coefficient of different rice varieties in different seasons and their application in irrigation planning

Methodology:

The study was conducted at BRRI farm, Gazipur during Aus, T. Aman and Boro seasons of 2004-05. The mean daily evapotranspiration (ET) rates was measured in rice field by closed bottom lysimeters. Meteorological daily data of the following variables were collected from BMD: i) minimum temperature, ii) maximum temperature, iii) minimum relative humidity, iv) maximum relative humidity, v) sunshine hours vi) wind speed and vii) wind direction. Crop evapotranspiration was calculated from climatic data and by integrating directly the crop resistance, albedo and air resistance factors in the Penman-Monteith approach. The Penman-Monteith method was used for the estimation of the standard reference crop to determine its evapotranspiration rate, i.e., ETo Experimentally determined ratios of ETc/ETo, called crop coefficients (Kc), are used to relate ETc to ETo or ETc= Kc*ETo.

Source of Information: Proceedings of the BRRI Annual Internal Review for 2006, BRRI, Gazipur-1701, Bangladesh

Article Link (Online Journal):

Funding Source:

1. Government

Budget:

Total Budget (Tk.) :

Achievement/Findings:

In Aus season, the mean daily evapotranspiration (ET) rates as measured in rice field by closed bottom lysimeters was 4.50 mm/day, for the season. In T. Aman season, the mean daily ET rate was 4.23 mm/day for the season. Similarly in Boro season, the mean daily ET rate was 4.6 mm/day for the whole growing season. There were little variations in ET rates among the varieties. The ET rate in Aus season was slightly higher than that in T Aman season and it was highest in Boro season. In Aus season, the Kc values ranged from 1.12 to 1.17. The highest value was obtained from BRRI dhan39 and the lowest from BR3. There was no wide variation in Kc values among the varieties. In T. Aman season, these values ranged from 1.03 to 1.07. In this season the difference in Kc values for different varieties was negligible. Similarly in Boro season it varies from 1.14 to 1.19. The Kc values in Boro season were slightly higher than those of Aus and T Aman seasons

Knowledge Management: Report/Proceedings