Impact of Variation in Agro-Meteorological Parameters on Wheat Production and Comparison of Yield Predicted by Agro-Meteorological Indices with Remote-Sensing Data

Abstract

Agricultural productivity of any region can be defined by agro-meteorological parameters. Six meteorological indices, namely Growing Degree-Days (GDD), Accumulated Growing Degree- Days (AGDD), Helio Thermal Units (HTU), Photo Thermal Units (PTU), Temperature Difference (TD) and Vapour Pressure Deficit (VPD) were computed from daily meteorological data, to analyze the impact of agro-meteorological parameters on wheat production for drought and wet years for the Shaheed Bhagat Singh Nagar (SBS) district of Punjab, India, for the years 2007–08 and 2010–11. The yields predicted with agro-meteorological index models were close to the actual yields for both the drought and wet years. The % relative deviation (RD) for both years was less than 5 per cent. The minimum RD was associated with AGDD (2.54%) and PTU (0.77%) for the drought year (2007–08) and the wet year (2010–11), respectively, and RD was maximum in the case of HTU (−4.73% and 4.34%) for both years. An agro-meteorological multiple regression model for the prediction of wheat yield for the wet year 2010−11 (RD = 0.08%) was closer to the actual yield than that for the dry year 2007–08 (RD =−12.50%). Results of wheat yield predicted by spectral vegetation indices (remote-sensing data) were closer to the actual yield than those predicted by agro-meteorological indices.