Observed and simulated responses of two sorghum cultivars to different water regimes uri icon

abstract

  • The responses to different water treatments of two sorghum (Sorghum bicolor (L.) Moench) cultivars, a hybrid (CSH 8) and a local variety (M 35-1), were studied on an Alfisol (Udic Rhodustalfs) at ICRISAT Centre, Patancheru during the post-rainy seasons of 1979/1980 and 1980/1981. Two water treatments, irrigated and drought-stress, were created by applying water five or three times during each of the growing seasons. Observed responses were compared with the simulated data using the sorghum simulation model SORGF. Neither observed nor simulated durations of growth stages were affected by drought-stress. Comparisons between observed and simulated duration of growth stages showed that the model simulated phenological development with good accuracy. Drought-stress coefficient calculations were based on the availability of water in the soil profile; simulated drought-stress coefficients agreed well with observed values. Observed and simulated grain yields of CSH 8 were higher than those of M 35-1 under both the irrigated and drought-stressed conditions. The correlation coefficients between observed and simulated total dry matter and grain yield data pooled over two water treatments, two cultivars, and two seasons were respectively 0.80 and 0.92. Comparisons between observed and simulated reductions in TDM and grain yield showed that the model is sufficiently sensitive to simulate the response of sorghum to drought-stress

publication date

  • 1987
  • 1987