Shoot water content and reference evapotranspiration for determination of crop evapotranspiration
Determination of water requirement for crops in resource limited areas is challenging, yet worsened by the common assumption that all crop varieties within a species have similar water requirements. The objective of the study was to indirectly determine crop evapotranspiration of soybean varieties,...
| Main Authors: | , , , |
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| Format: | Journal Article |
| Language: | Inglés |
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African Journals Online
2017
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| Subjects: | |
| Online Access: | https://hdl.handle.net/10568/89953 |
| _version_ | 1855518626059124736 |
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| author | Omondi, J.O. Mungai, N.W. Ouma, J.P. Baijukya, Frederick P. |
| author_browse | Baijukya, Frederick P. Mungai, N.W. Omondi, J.O. Ouma, J.P. |
| author_facet | Omondi, J.O. Mungai, N.W. Ouma, J.P. Baijukya, Frederick P. |
| author_sort | Omondi, J.O. |
| collection | Repository of Agricultural Research Outputs (CGSpace) |
| description | Determination of water requirement for crops in resource limited areas is challenging, yet worsened by the common assumption that all crop varieties within a species have similar water requirements. The objective of the study was to indirectly determine crop evapotranspiration of soybean varieties, using reference evapotranspiration and shoot water content under tillage and no tillage cultivation. The treatments were no tillage and conventional tillage as main plots, and soybean varieties Nyala, SB19, and SB20 as sub-plots, replicated three times. Crop evapotranspiration (ETC) and crop coefficient (KC) were different among varieties, and increased during growth period. SB20 had the highest KC (0.8437 at 87 days after planting - DAP); followed by SB19 (0.7888 at 70 DAP), and Nyala (0.7026 at 66 DAP). Conversely,water use efficiency (WUE) was 0.58 in SB19, 0.52 in Nyala, and 0.47 in SB20.Validation of the calculated ETC using a crop production function showed a correlation of r = 0.97 between the observed and predicted yields of the three varieties. Furthermore, the normalised root mean square error (NRMSE) and the index of agreement (d) were 0.14 and 0.87, respectively indicating accurate fit. Calculated crop coefficient strongly correlated with observed shoot water content of Nyala (R2 = 1), SB19 (R2 = 1), and SB20 (R2 = 1). |
| format | Journal Article |
| id | CGSpace89953 |
| institution | CGIAR Consortium |
| language | Inglés |
| publishDate | 2017 |
| publishDateRange | 2017 |
| publishDateSort | 2017 |
| publisher | African Journals Online |
| publisherStr | African Journals Online |
| record_format | dspace |
| spelling | CGSpace899532025-12-08T09:54:28Z Shoot water content and reference evapotranspiration for determination of crop evapotranspiration Omondi, J.O. Mungai, N.W. Ouma, J.P. Baijukya, Frederick P. crop evaporation glycine max shoot soyabean transpiration Determination of water requirement for crops in resource limited areas is challenging, yet worsened by the common assumption that all crop varieties within a species have similar water requirements. The objective of the study was to indirectly determine crop evapotranspiration of soybean varieties, using reference evapotranspiration and shoot water content under tillage and no tillage cultivation. The treatments were no tillage and conventional tillage as main plots, and soybean varieties Nyala, SB19, and SB20 as sub-plots, replicated three times. Crop evapotranspiration (ETC) and crop coefficient (KC) were different among varieties, and increased during growth period. SB20 had the highest KC (0.8437 at 87 days after planting - DAP); followed by SB19 (0.7888 at 70 DAP), and Nyala (0.7026 at 66 DAP). Conversely,water use efficiency (WUE) was 0.58 in SB19, 0.52 in Nyala, and 0.47 in SB20.Validation of the calculated ETC using a crop production function showed a correlation of r = 0.97 between the observed and predicted yields of the three varieties. Furthermore, the normalised root mean square error (NRMSE) and the index of agreement (d) were 0.14 and 0.87, respectively indicating accurate fit. Calculated crop coefficient strongly correlated with observed shoot water content of Nyala (R2 = 1), SB19 (R2 = 1), and SB20 (R2 = 1). 2017 2018-01-09T09:23:51Z 2018-01-09T09:23:51Z Journal Article https://hdl.handle.net/10568/89953 en Open Access application/pdf African Journals Online Omondi, J.O., Mungai, N.W., Ouma, J.P. & Baijukya, F.P. (2017). Shoot water content and reference evapotranspiration for determination of crop evapotranspiration. African Crop Science Journal, 25(4), 387-403. |
| spellingShingle | crop evaporation glycine max shoot soyabean transpiration Omondi, J.O. Mungai, N.W. Ouma, J.P. Baijukya, Frederick P. Shoot water content and reference evapotranspiration for determination of crop evapotranspiration |
| title | Shoot water content and reference evapotranspiration for determination of crop evapotranspiration |
| title_full | Shoot water content and reference evapotranspiration for determination of crop evapotranspiration |
| title_fullStr | Shoot water content and reference evapotranspiration for determination of crop evapotranspiration |
| title_full_unstemmed | Shoot water content and reference evapotranspiration for determination of crop evapotranspiration |
| title_short | Shoot water content and reference evapotranspiration for determination of crop evapotranspiration |
| title_sort | shoot water content and reference evapotranspiration for determination of crop evapotranspiration |
| topic | crop evaporation glycine max shoot soyabean transpiration |
| url | https://hdl.handle.net/10568/89953 |
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