Modeling the Effect of Environmental Factors on sorghum Growth and Development

The yrelds ofrarnledsorghumrn the semr-arid regions in general are low and vary from year to year. An understanding of the interactions between the physical environment and the genotype is important to Increase and stabilize production of sorghum. This information, through the systems-simulation approach could be used to model sorghum growth and development. The gran sorghum growth simulation model-SORGF-was used as the basis to evaluate crop weather interactions. A multilocation study was conducted in India over a period of 4 years to evaluate the growth and development of selected sorghum genotypes of varying maturity durations. Preliminary results suggested that several subroutines of the SORGF model needed modrbcatrons to simulate accurately the effect of environmental factors. Algorithms of the SORGF model dealing with light interception, phenology, leaf senescence, sol1 water, and total dry matter accumulalron and its partitioning to grain have been revised The improvement resulting from the revisions made rn each of the above subroutrnes are compared wrlh the freld data and the simulationes sults olthe ongrnalSORGF model The use of the SORGF model for rrrrgatron scheduling and lrrst-order screenrng of envrronments lor sorghum producoon are illustrate