Pre-harvest Forecasting Models for Kharif Rice Yield in South Gujarat Using Composite Weather Indices

The pre-harvest forecasting models were developed for Kharif rice yield forecasts for Navsari, Surat and Tapi districts respectively. The data of rice yield and the weather parameters from 1995 to 2017 was used for developing statistical models for three districts of south Gujarat. The weather indices like Z41, Z50, Z231, Z241, Z341, Z351 and Time were able to forecast the yield of rice for Navsari district. Similarly, Z41, Z51, Z131, Z141, Z231, Z241, Z351 and Time were found to be most efficient predictors for Surat district. Only two variables i.e., Z241 and Z251 were found to be able to forecast the rice yield in Tapi district. Models were validated with 3 years (2018, 2019 and 2020) data. Results indicated that models explained 53 to 93 percent variations for rice yield during F1 stage, 54 to 92 percent variation for rice yield during F2 stage and 52 to 93 percent variations during F3 stage for rice yield in three districts. Hence these models can be used to some extent for forecast the yield in different districts of south Gujarat a few months before harvest.