Assessment and application of the crop growth simulation model CERES-Rice for rice production in the Central Plain, Thailand | |
| Author | Sripan Cheyglinted |
| Call Number | AIT Diss. no.AS-01-05 |
| Subject(s) | Crops--Growth--Computer simulation--Thailand Rice--Computer simulation--Thailand |
| Note | A dissertation submitted in partial fulfillment ofthe requirements for the degree of Doctor of Technical Science, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Dissertation ;no. AS-01-05 |
| Abstract | Crop modeling has extensively been used for decision making on inputs and predicting crop growth and yield. CERES—Rice model is One of the crop models used in Decision Support Systems for Agrotechnology Transfer (DSSAT) software. However, use of this model is still at the infant stage in Thailand. The main objective of this study was to assess the CERES—Rice model for rice cultivation in the Central Plain of Thailand and to estimate and compare rice yield with some varieties and changes in N levels, and selected management practices under selected crop environments. This research consisted of three phases. At first, three experiments were conducted with selected rice varieties (viz. RD23, HTA, HSP, SPR90 and KDMLIOS) to determine the genetic coefficients, and to examine their grain production with the application of 75 kg N/ha. In the second phase, the model was evaluated by predicting growth and yield of rice varieties at four locations in the Central Plain of Thailand. Thirdly, the model was used to simulate yield of the selected rice varieties using different field management practices : manipulation of N levels; residue management and suitable seedling age. At 75 kg N/ha, the model showed a good performance in predicting the timing of physiological stages (i.e. days to flowering and harvesting) and grain and straw yields of all rice varieties, except HTA as it suffered from sheath rot disease. In addition, the model was validated successfully by t-test and other statistical parameters (Bias, RMSE, R V and CV). It showed a gradual increase in yields of KDMLlOS variety and constant yields of RD23, HSP and SPR90 beyond the rate of 75 kg N/ha, but the Optimum .rate remained between 38— 75 kg N/ha. In contrast, observed grain yield continuously declined, which showed the model did not consider other limiting factors like weeds, diseases and insects. Lack of sensitivity to lodging caused over estimation of grain yield with increasing N levels which was a serious drawback of the model. In the application phase, the model showed that application of straw at 3 and 5 t/ha effectively increased grain yield of RD23, HSP and SPR90 in Pathum Thani province (acid sulfate soils). In addition, use of straw residue increased efficiency of applied N. Twenty five day—old seedlings were more suitable than 35 or 45 day seedlings, which were able to produce higher grain yield according to the model. The model Suggested that split application at each rate of N improves grain yield and N recovery. Finally, the spatial analysis showed that N at 75 kg/ha was more suitable to avoid lodging. Ranking of rice varieties according to yield performance showed SPR90> RD23=HSP>KDMLIOS, thus the SPR9O was the most suitable variety for the Central Plain, which had yield potential of 4,030 to 5,600 kg/ha. The Outputs of the model could provide support to researchers and officials in policy decisions for agriculture sector of Thailand. |
| Year | 2001 |
| Corresponding Series Added Entry | Asian Institute of Technology. Dissertation ; no. AS-01-05 |
| Type | Dissertation |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Aquatic Systems (AS) |
| Chairperson(s) | Singh, Gajendra; |
| Examination Committee(s) | Salokhe, V.M.;Ranamukhaarachchi, S.L.;Clemente, Roberto S.,; |
| Scholarship Donor(s) | Rajamangala Institute of Technology; |
| Degree | Thesis (Ph.D.) - Asian Institute of Technology |