Vol. 15, No. 2 SANDHU et al 147 Journal of Agrometeorology 15 (2) : 147-151 (December 2013) Effect of inter and intra seasonal variability in meteorological parameters on rice productivity in central Punjab* S S SANDHU, PRABHJYOT-KAUR, K K GILL and ASHU BALA School of Climate Change and Agricultural Meteorology, Punjab Agricultural University, Ludhiana-141 004 Email : ssandhu@pau.edu ABSTRACT A study was conducted to ascertain the role of meteorological parameters on year to year variability in rice yield in Punjab using 12 years (2000-11) data of Ludhiana district. The rice growing season was divided into three stages (entire rice season, vegetative stage and reproductive stage) and the meteorological data during these stages were correlated with the rice yields. Highly significant (p=0.05) positive correlation was noticed between grain yield and sunshine hours received during entire rice season and vegetative stage of the crop. The maximum temperature during entire rice season and vegetative stage was significantly (p=0.10) and positively correlated with grain yield. During all three stages maximum relative humidity had significantly negative correlation with grain yield. Rainfall during vegetative stage and number of rainy days during reproductive stage were significantly and negatively correlated with grain yield. After studying the deviation of meteorological parameters from respective normals during high and low yield years and the correlation of meteorological parameters with rice yield it can be concluded that in the central parts of the Punjab sunshine hours play a major role in determining the productivity of rice. Key words: Rice, Punjab, maximum, minimum, temperature, sunshine hours. * Paper presented in national seminar on “Climate change and Indian Agriculture : Slicing down the Uncertainty” held at CRIDA, Hyderabad during 22-23 January-2013 and reviewed for special issue of the Journal. Rice ( Oryza sativa L.) is one of the most important cereals cultivated in the world as well as in India and Punjab. It is a staple food of more than 50 per cent of the world’s population (Fageria, 2007) and it supplied 20 per cent of calories required by world and 31 per cent required by the Indian population, in the year 2005 (Anonymous, 2011). More than one billion farmers from over a hundred countries make their living from rice. More than 90 per cent of the world’s rice is grown and consumed in Asia alone (Sharma, 2003). On an average, an Indian consumes 83 kg rice per year. According to Agricultural Policy Vision 2020 of ICAR, India will need 112.4 million tonnes of rice in the year 2020. The plants grow to their best under a range of abiotic factors and any deviation from optimum range will lead to aberrant changes in physiological processes in the plant and the plant may experience stress (Orcutt and Nilsen, 2000). Under changing climatic scenario, extreme of temperatures and rainfall events are predicted. These changes will most likely make the stresses even more common and severe. Increasing temperature may be a potential threat to rice production because high temperature can affect rice production at all stages of development, particularly during flowering, when it causes spikelet sterility. It also increases plant respiration, affects photosynthesis and shortens the grain-filling period, all of which leads to lower productivity (Peng et al., 2004). Samui (1999) reported that in India the maximum rice yield was observed when rainfall ranged between 100-115 cm, sunshine hours between 250-350 hours for photo-insensitive varieties, maximum and minimum temperature ranged between 29-32 o C and 23-25 o C, respectively. These parameters vary yearly and intra and inter-seasonal variations play a pivotal role in determining the final crop yields (Prabhjyot-Kaur and Hundal, 2009). Therefore, the present study was conducted, to analyze the effect of variations in inter- and intra-seasonal meteorological parameters on rice yields in Punjab. MATERIALS AND METHODS The historical rice yields of district Ludhiana for the past twelve years (2000-2011) were taken from the “Statistical Abstracts” of Punjab. Meteorological data required for the study was collected from the Meteorological Observatory,