Ecological Environmental Variability Influence Growth and Yield Potential of Rice under Northern Climatic Scenario

To evaluate the response of various rice genotypes to environmental variability and fluctuation in temperature for growth and development of the plant, an experiment was conducted at Agriculture Research Institute (N) Mingora Swat, Pakistan, during summer 2011. The site is located at 34° and 36° North latitude and 72° and 73° East longitude and at an altitude of 975 m above sea level. Experimental site falls in temperate region where the average annual precipitation is ranges from 1000 to 1200 mm. Seven genotypes (PARC 403, OM5627, IR64, IR8225-9-3-2-3, CIBOGO, GA-5015, and Fakhre Malakand) were evaluated for growth and yield parameters in respect of seasonal variation of transplanting. Five transplanting dates, (D1 = 25th May, D2 = 9th June, D3 = 24th June, D4 = 9th July, and D5 = 25th July) were used during the study. Results divulge that optimum temperature for well growth and development was found on D2 (9th June), taken less number of days to 50% flowering (72), less number of days taken physiological maturity (112), produced taller plant height (88.62 cm), maximum tiller plant^–1 (20.3 cm), panicle length (22.0 and 22.0 cm), paddies panicle^–1(191 and 193), 1000 paddy weight (18.15 and 18.16 g) and paddy yield (5.65 and 5.53 t ha^–1) respectively. As the transplanting was delayed decreased in yield contributing parameters was noted. Panicle length (17.9 cm), paddies panicle^–1 (176.14) and paddy yield (4.12 t ha^–1) was observed when transplanting was done on D5, while D1 and D4 were at par valued in tiller plant^–1, Panicle length, 1000 paddy weight, and paddy yield respectively. Fakhre-e-Malakand was found best among the tested genotypes for early maturity, maximum plant height, highest tillers plant^–1 (22.2), panicle length (21.8 cm), paddies panicle^–1 (197.7), 1000 paddy weight (19.2 g) and paddy yield (6.49 t ha–1) under the northern climatic scenario.