Developing a dynamic yield and growth model for saffron under different irrigation regimes

Document Type: Research Paper

Authors

Irrigation Department, Shiraz University, Shiraz, I.R. of Iran.

Abstract

Better irrigation management and more efficient management of crop production
require modeling of plant growth and crop yield. More applicable models are usually
simple and requires less and accessible inputs. The objective of this study was to
develop a model for growth and yield prediction of saffron under various irrigation
regimes. In this modeling soil water budget and other simple relationships for
evapotranspiration partitioning, leaf area index determination and leaf dry mattertranspiration
function, corm-transpiration function and saffron-corm function were
used. The developed model was calibrated based on available data of basin irrigation
experiment under different irrigation regimes and verified based on independent data
under different climatic conditions. In calibration, the comparison between predicted
and measured values of different crop parameters did not show any significant
difference (P=0.05) and model was able to estimate LAI (with NRMSE=0.16),
crop evapotranspiration (NRMSE=0.19), surface evaporation (NRMSE=0.22), leaf
dry matter (NRMSE=0.33) and corm yield (NRMSE=0.19) and saffron yield
(NRMSE=0.16) properly. In validation, the statistical results of comparison between
predicted and measured values of various crop parameters were different and model
was able to estimate corm and saffron yield with acceptable accuracy. Furthermore,
this model might be used only for saffron crop because the incorporated crop
functions are developed for saffron.

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