Vol. 6, Issue 6 (2017)
Effect of temperature regimes on physiological traits of rice (Oryza sativa L.) genotypes for high temperature tolerance
Author(s): Amareshkumar J, Dr. Amaregouda A, Dr. Mahantashivayogayya K and Dr. RP Patil
Abstract: High temperature stress is the one of the most important environmental factors that influencing growth, development, and yield of rice crop. The present paper studies the effects of temperature regimes on various physiological parameters at different stages of growth for high temperature tolerance using the 50 IRRI and Indian rice genotypes with five check (Local, national and international) varieties were evaluated during normal sown (December-2014) and late sown conditions (January 2015). Result of the experiment reveals that late sowing of genotypes particularly in the month of January has shown the decreased various morpho-physiological responses and yield attributes than the normal sown genotypes. Grain yield was lowest under late sown condition (11.92 per cent reduction) as compared to normal sown condition, which was expected that plant experienced the high temperature stress mainly during flowering and grain filling stages. The results of mean sum of squares due to the genotypes and their interaction were significant for different physiological parameters. Finally, among the screened genotypes EC792239, EC792185, EC792179, EC792240 and EC792316 are identified as heat stress tolerant genotypes. Hence, they are shown better performance for different physiological parameters like photosynthetic rate (24.72 μ mol CO2 m-2 s-1), transpiration rate (6.38 μ mol CO2 m-2s-1), and by maintaining the canopy temperature (25.42 oC). They could be used as potential donors for development of heat stress tolerant variety.
How to cite this article:
Amareshkumar J, Dr. Amaregouda A, Dr. Mahantashivayogayya K and Dr. RP Patil. Effect of temperature regimes on physiological traits of rice (Oryza sativa L.) genotypes for high temperature tolerance. Journal of Pharmacognosy and Phytochemistry. 2017; 6(6): 2376-2380.