Natural Response of Rice Seedlings under Cold Conditions

Abstract

Rice (Oryza sativa L., Poaceae) is the primary source of food for billions of people throughout the world and around 90% of the cultivated area under rice is in Asia. Rice is the majorly grown during both seasons and in Rabi season the seedlings are raised in exposure to the cold months and hence, cold tolerant rice varieties are the prerequisite for rice cultivation. Among the districts of Telangana, Nizamabad, records the lowest mean minimum temperature ranging from 11-16°C over past ten years. The main aim of the study was to identify cold tolerant genotypes.  The experiment was conducted to evaluate 35 genotypes of rice for cold tolerance under field conditions. Sprouted seeds of these genotypes were sown in nursery during Rabi 2017-18. The germination percentage was recorded at 15 days after sowing (DAS) and 30 DAS, scoring for cold was done and chlorophyll content through SPAD meter were taken. Akshaydhan and Krishna Hamsa were least affected by cold and scored 1 considering them as cold tolerant and can be used as donors in crossing programs.