Crop water stress index and yield of water-deficit-stressed alfalfa
The yield relationship of water-deficit-stressed alfalfa (Medicago sativa L.) with the Crop Water Stress Index (CWSI) may be dynamic over the alfalfa harvest period. This investigation was conducted to define the alfalfa yield-CWSI relationship(s), to test possible advantages of using the CWSI over...
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| Format: | Article |
| Language: | English |
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American Society of Agronomy
1988
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| Online Access: | http://psasir.upm.edu.my/id/eprint/39535/ http://psasir.upm.edu.my/id/eprint/39535/1/20%20-%20Crop%20water%20stress%20index%20and%20yield%20of%20water-deficit-stressed%20alfalfa.pdf |
| _version_ | 1848849169250254848 |
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| author | Hattendorf, M. J. Carlson, R. E. Abdul Halim, Ridzwan Buxton, D. R. |
| author_facet | Hattendorf, M. J. Carlson, R. E. Abdul Halim, Ridzwan Buxton, D. R. |
| author_sort | Hattendorf, M. J. |
| building | UPM Institutional Repository |
| collection | Online Access |
| description | The yield relationship of water-deficit-stressed alfalfa (Medicago sativa L.) with the Crop Water Stress Index (CWSI) may be dynamic over the alfalfa harvest period. This investigation was conducted to define the alfalfa yield-CWSI relationship(s), to test possible advantages of using the CWSI over the canopy-minus-air temperature (Tc−Ta) differential, and to combine the yield-CWSI relationship with a growth function. ‘Apollo 11’ alfalfa was grown for 2 yr in 100-L containers set into the ground and protected from rain by a movable shelter. The soil was a Nicollet silt loam topsoil (fine-loamy, mixed, mesic Aquic Hapludoll). Treatments were irrigation levels of 112, 100, 88, 77, and 65% field capacity. Five harvests were taken at 7-d intervals beginning 21 d after an initial clipping. Canopy temperatures were taken daily with an infrared thermometer. A series of exponential yield-CWSI curves resulted from the sequential harvests. Yield reductions of about 10 and 20% resulted from mean CWSI of 0.05 and 0.10, respectively, over 42-d periods. The Gompertz growth function was modified for water-deficit-stress by combining it with the exponential yield-CWSI relationship. Vapor-pressure deficit (VPD) effectively normalized the Tc−Ta data, allowing yield data of the 2 yr to be combined in the yield-mean CWSI relationship. Yield and Tc−Ta data not normalized for VPD showed clear
separation by year for slight VPD differences. Alfalfa yield response to water-deficit-stress over time appeared to be adequately described by the combined Gompertz function and the yield-CWSI (Tc−Ta normalized for VPD) curves |
| first_indexed | 2025-11-15T09:46:07Z |
| format | Article |
| id | upm-39535 |
| institution | Universiti Putra Malaysia |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-15T09:46:07Z |
| publishDate | 1988 |
| publisher | American Society of Agronomy |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | upm-395352015-08-11T05:48:38Z http://psasir.upm.edu.my/id/eprint/39535/ Crop water stress index and yield of water-deficit-stressed alfalfa Hattendorf, M. J. Carlson, R. E. Abdul Halim, Ridzwan Buxton, D. R. The yield relationship of water-deficit-stressed alfalfa (Medicago sativa L.) with the Crop Water Stress Index (CWSI) may be dynamic over the alfalfa harvest period. This investigation was conducted to define the alfalfa yield-CWSI relationship(s), to test possible advantages of using the CWSI over the canopy-minus-air temperature (Tc−Ta) differential, and to combine the yield-CWSI relationship with a growth function. ‘Apollo 11’ alfalfa was grown for 2 yr in 100-L containers set into the ground and protected from rain by a movable shelter. The soil was a Nicollet silt loam topsoil (fine-loamy, mixed, mesic Aquic Hapludoll). Treatments were irrigation levels of 112, 100, 88, 77, and 65% field capacity. Five harvests were taken at 7-d intervals beginning 21 d after an initial clipping. Canopy temperatures were taken daily with an infrared thermometer. A series of exponential yield-CWSI curves resulted from the sequential harvests. Yield reductions of about 10 and 20% resulted from mean CWSI of 0.05 and 0.10, respectively, over 42-d periods. The Gompertz growth function was modified for water-deficit-stress by combining it with the exponential yield-CWSI relationship. Vapor-pressure deficit (VPD) effectively normalized the Tc−Ta data, allowing yield data of the 2 yr to be combined in the yield-mean CWSI relationship. Yield and Tc−Ta data not normalized for VPD showed clear separation by year for slight VPD differences. Alfalfa yield response to water-deficit-stress over time appeared to be adequately described by the combined Gompertz function and the yield-CWSI (Tc−Ta normalized for VPD) curves American Society of Agronomy 1988-11 Article PeerReviewed application/pdf en http://psasir.upm.edu.my/id/eprint/39535/1/20%20-%20Crop%20water%20stress%20index%20and%20yield%20of%20water-deficit-stressed%20alfalfa.pdf Hattendorf, M. J. and Carlson, R. E. and Abdul Halim, Ridzwan and Buxton, D. R. (1988) Crop water stress index and yield of water-deficit-stressed alfalfa. Agronomy Journal, 80 (6). pp. 871-875. ISSN 0002-1962; ESSN: 1435-0645 |
| spellingShingle | Hattendorf, M. J. Carlson, R. E. Abdul Halim, Ridzwan Buxton, D. R. Crop water stress index and yield of water-deficit-stressed alfalfa |
| title | Crop water stress index and yield of water-deficit-stressed alfalfa |
| title_full | Crop water stress index and yield of water-deficit-stressed alfalfa |
| title_fullStr | Crop water stress index and yield of water-deficit-stressed alfalfa |
| title_full_unstemmed | Crop water stress index and yield of water-deficit-stressed alfalfa |
| title_short | Crop water stress index and yield of water-deficit-stressed alfalfa |
| title_sort | crop water stress index and yield of water-deficit-stressed alfalfa |
| url | http://psasir.upm.edu.my/id/eprint/39535/ http://psasir.upm.edu.my/id/eprint/39535/1/20%20-%20Crop%20water%20stress%20index%20and%20yield%20of%20water-deficit-stressed%20alfalfa.pdf |