A simple model for chickpea development, growth and yield

Chickpea (Cicer arietinum L.) yield is unstable and low in major producer countries. A robust crop model can assist in evaluation of possible genetic improvements and cultural management practices to improve yield. The objectives of this study were to develop and test a chickpea simulation model that could be used across a wide range of environments. This model simulates phenological development, leaf development and senescence, mass partitioning, plant nitrogen balance, yield formation and soil water balance. Responses of crop processes to environmental factors of solar radiation, photoperiod, temperature, nitrogen and water availability, and genotype differences were included in the model. The model uses a daily time step and readily available weather and soil information. The model was tested using independent data from a wide range of growth and environmental conditions. In most cases, simulated grain yield were similar to observed yield (ranging from 20 to 379 g m−2) with a root mean square root of 26 g m−2 (15% of average measured yield). It was concluded that the model generality, i.e., constant parameters for genotypes across locations, and applicability to a wide range of environmental conditions factors made this model especially useful.

► Advances in understanding chickpea allowed important upgrades in modeling this crop.
► A major feature of the upgraded model was the inclusion of a nitrogen budget.
► The model included photoperiod sensitivity and resource partitioning among tissues.
► The upgraded model gave good simulation results over a wide range of environments.