Microclimatic variations under different planting methods of rice, Oryza sativa L

Field experiments were conducted at the research farm of School of Climate Change and Agricultural Meteorology, Punjab Agricultural University, Ludhiana, Punjab during Kharif season of 2012 and 2013 to study the microclimate particularly relative humidity and canopy temperature in rice crop canopy. The rice varieties PR-118 and PR-116 were transplanted on three dates viz 15 June, 30 June and 15 July by two planting methods (bed and conventional planting). Photosynthetically active radiation (PAR) and canopy temperature were measured at different growth stages. PAR interception was found to be highest in crop transplanted on 15 June (D₁) followed by 30 June (D₂) and 15 July (D₃). So far as the method of transplanting is concerned PAR interception was higher (up to 5%) in bed planting (M₁) as compared to conventional planting (M₂). Higher relative humidity was recorded within crop canopy at flowering stage than panicle initiation stage during both the crop seasons. During rice growing season 2013 higher relative humidity was recorded as compared to 2012. The canopy temperature was slightly higher in bed planted method as compared to conventional method.