Determining the performance and sensitivity of the cropgro V4.7.5 plant growth model in eastern Mediterranean conditions

This research was carried out to determine the performance and sensitivity of the CROPGRO V4.7.5 model in determining the effects of different irrigation programs on yield and water use in peanut (NC-7) irrigated with drip irrigation system in Eastern Mediterranean conditions in 2014 and 2015. In the irrigation program, 3 different irrigation intervals (SA) are formed from accumulated evaporation values (SA1: ΣEo = 25 ± 2.5 mm; SA2: ΣEo = 50 ± 5 mm; SA3: ΣEo = 75 ± 5 mm), 4 different irrigation levels (I1 = 0.50; I2 = 0.75; I3 = 1.00; I4 = 1.25). According to the results obtained; irrigation interval and irrigation level interaction was found to significantly affect total peanut grain yield at 1% error level statistically. In both experimental years, the highest yield was taken from SA2-125 and the lowest yield was taken from SA3-50. The total amount of irrigation water applied to the subjects varied between 406-1059 mm and plant water consumption values between 516-1034 mm by years. Irrigation interval and irrigation level; The yield of peanuts significantly affected dry matter amount, leaf area, harvest index, water use efficiency (WUE) and irrigation water use efficiency (IWUE) values. After all; SA2-125 irrigation program can be recommended for high yields in the region. The output of CROPGRO-Peanut model showed that the simulated values of growth parameters, phenology and seed yield of peanut were close to the corresponding measured values. Determination coefficient (R2) values between simulated and observed peanut yield values changed between 0.52-0.88 in 2014 and 0.50-0.96 in 2015 depending on the irrigation interval. Thus, the model could be used to predict the seed yield of peanut accurately under different irrigation management conditions.