Weather Variability during Wheat Growing Season in Central Plain Region of Punjab
L. K. Dhaliwal *
Department of Climate Change and Agricultural Meteorology, Punjab Agricultural University, Ludhiana, Punjab, India.
Jashandeep Kaur
Department of Agriculture and Farmers Welfare, Punjab, India.
Jagjeewan Singh
Krishi Vigyan Kendra, Barnala, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, Punjab, India.
*Author to whom correspondence should be addressed.
Abstract
Wheat production data in relation to weather variability in central plain region of Punjab using the annual time series data were analyzed from 1990 to 2017. The analysis indicates maximum and minimum temperatures has increased by about 0.015 ºC year-1 and 0.044 ºC year-1 respectively and rainfall trend was negative (-0.028 mm year-1) during the wheat growing season (October to March). Both maximum and minimum temperatures indicate increasing trend from late vegetative stage to maturity except for the maximum temperature which shows decreasing trend during the month of January. Deviation (positive or negative) in weather parameters from long term average at different phenological stages caused significantly reduction in wheat yield. The highest variability among weather parameters was observed in rainfall (-5.7 mm and +27.5 mm) especially during reproductive phase of wheat crop in high (2012) and low (2015) yield years respectively which might be the cause of low grain yield. During the period of study, maximum negative correlation was observed in minimum temperature during crop growing season of wheat crop. The climatic changes resulted in substantial loss in wheat production which might be due to shorter life cycle, pollen abortion and poor grain quality by rising temperature and rainfall variability.
Keywords: Terminal heat stress, crop phenology, rainfall, pollen fertility, wheat yield