Assessing the impact of temperature and rainfall on mustard yield through detrended production index

The present study aims to evaluate the individual and combined impact of temperature and rainfall on mustard yield through DPI for five districts, viz., Hooghly, Nadia, Burdwan, Mursidabad and South 24 Parganas of West Bengal based on 18 years. The selected study areas belong to different agro-climatic zones of the state, namely the old alluvial zone, new alluvial zone and coastal saline zone. The mustard growing season in these districts starts from the middle of October and continues upto the middle of January (Rabi season). The Detrended Production Index (DPI) was calculated based on the actual annual yield of the study period and the computed trend value. Maximum and minimum temperatures along with rainfall data were given prime importance in this case. The effect of temperature and rainfall as well as their interaction is clarified through the generated DPI. The yield variation of mustard in the five districts of West Bengal due to prime weather parameters are shown by this process. Two equations, one based on max and min temperatureand another incorporating the combined effect of temperature and rainfall, are the outcomes of the study. They can be easily utilized to form models of yield forecast. The clear indication towards yield reduction due to enhanced temperature will guide in decision making process. Modification of the sowing window is an important solution for mustard cultivation in the study region if the temperature continues to increase in the future. The results of this work strongly support the idea of engaging DPI to evaluate the impacts of prime weather parameters on crop production and generate the yield forecasting models based on that.