Progress 09/15/05 to 09/14/07
Outputs Field experiments were conducted during a two-year period with the principal goal of utilizing the CERES-Maize and CROPGRO models as a tool to predict better management practices for producing maize and common bean (Phaseolus vulgaris L.) on a bigger scale in Puerto Rico. Duration of phenological stages and genetic coefficients were estimated for three locally adapted open pollinated maize cultivars: "Mayorbela improved", "Diente de Caballo", "Churo", and a genetically modified hybrid (GMO). Also, genetic coefficients, yield components, and other agronomic traits of two common bean populations 'ICA Pijao x Montcalm' and 'Jamapa x Calima' were estimated. Measured genetic coefficients for maize were similar to published values. 'Mayorbela improved' yield and overall performance was similar to that of GMO and higher than that of the other cultivars evaluated. The data measured under field conditions and published values of the three open pollinated maize cultivars were
utilized to validate the CERES-Maize model. Even though phenology and yield components were not simulated accurately, yield predictions were fairly accurate for 'Mayorbela improved'. Narrow sense heritabilities were estimated for common bean seed yield components and phenological and agronomic traits used by CROPGRO model. Heritabilities for seed yield and mean number of pods per plant were intermediate for both populations. On the other hand, the heritabilities of mean number of seed per pod and mean seed weight were high. The magnitude of the heritabilities for determinate and indeterminate lines in the ICA Pijao x Montcalm was similar for that of the seed yield components. However, the heritability of emergence to flowering (EM-FL) of indeterminate lines of the ICA Pijao x Montcalm population was lower than the heritability of EM-FL of the determinate lines.
Impacts Field estimation of genetic coefficients facilitates the use of simulation models to predict maize and bean better management practices for acceptable yields and to reduce production costs for the conditions prevailing in four valleys, reserved by a state law, to be used exclusively for agriculture. For beans, the magnitude of the heritabilities of all the traits studied is sufficiently large to permit selection in a bean breeding program. Moreover, there is sufficient genetic variability among the lines in both populations to possibly permit the identification of molecular markers (QTL) associated with the genetic coefficients used in the crop model.
Publications
- Saliceti Rivera, M. 2005. Evaluacion de dos poblaciones de habichuela (Phaseolus vulgaris L.) para ser utilizada en el modelo de simulacion CROPGRO. MS thesis. Department of Agronomy and Soils. University of Puerto Rico.
- Esteves Nieves, M., 2007. Determinacion de los coeficientes geneticos en maiz para ser utilizados en el modelo CERES-Maize. MS thesis. Department of Agronomy and Soils. University of Puerto Rico.
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Progress 09/15/05 to 09/14/06
Outputs A second field trial was established at Lajas substation to estimate genetic coefficient for three open pollinated maize cultivars, 'Mayorbela improved', 'Diente de Caballo', 'Churo', and a genetically modified hybrid for Bt planted on a Vertic Haplustert March 2, 2005. Maize fertilization, pest and disease control, weed control, drip irrigation were managed toward optimal conditions to guarantee the expression of genetic potential. Maize was planted at l9 cm between plants and 90 cm between rows. Growing Degree Days between phenological stages were calculated by using the standard method. The hybrid showed the earliest time to reach silking date (52 dap) and physiological maturity (90 dap) and the lowest leaf number, with 16. 'Mayorbela' and the 'Diente de Caballo' took the longest to reach maturity (95 dap). The hybrid produced the highest yield with 3,845 kg/ha. In both years, yields were lower than average commercial yields, however maize was planted at low plant
population. It is important to point out that P1 estimates obtained in 2005 (cultivars stayed longer in the juvenile phase) were higher than those obtained in 2004. No cultivar reached a LAI of 1.5, meaning that they may not have reached full development. No significant differences were found among cultivars for total LAI and the interaction between time of sampling and cultivar was significant. No significant differences were found among maize cultivars for total dry matter accumulation non was there significant interaction between time of sampling and cultivars. During the upcoming months we plan to validate the CERES-Maize and CROPGRO-dry bean crop models. Also, there is a genetic relationship among the dry bean lines in the 'ICA Pijao x Montcalm' and the 'Jamapa x Calima' populations; we would like to use the data to determine the magnitude of the genetic contribution to the expression of traits in the crop model.
Impacts Dr. Eduardo Vallejos has used a portion of the data collected for the CROPGRO-Dry Bean crop model for molecular marker and genetic mapping research at the University of Florida. Marilis Esteves Nieves, a graduate student supported by this project, scheduled for completing her of master's requirements by November 2006.
Publications
- Saliceti, M., E. Roman-Paoli and J.S. Beaver. Repeatability of morphological & phenological traits used by the Cropgro-Dry Bean crop model. Paper presented at the Annual Meeting of the Bean Improvement Cooperative Program held in Newark, Delaware. 30 October to 3 November 2005
- Esteves-Nieves, M., E. Roman-Paoli, and J. Beaver. Utilizacion de la simulacion como herramienta para el manejo a gran escala de habichuela y maiz. Poster presented at 52th PCCMCA Annual Meeting. April 24-28, 2006. Montelimar, Nicaragua
- Saliceti Rivera, M. 2005. Evaluacion de dos poblaciones de habichuela (Phaseolus vulgaris L.) para ser utilizadas en el modelo de simulacion CROPGRO. Recinto Universitario de Mayaguez, Universidad de Puerto Rico. Master Thesis. http://grad.uprm.edu/tesis/salicetirivera.pdf.
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