Identification of genomic regions associated with yield in rice under low nitrogen conditions

Abstract

Rice is one of the most important crops for majority of the world, both as source of income and food supply. During the period of last half century, global yields of important cereal crops such as maize, rice and wheat have increased linearly, which can be attributed to the technological developments and green revolution in the history. The development of high nitrogen responsive semi dwarf varieties with sd-1 gene played a significant role in achieving the target yield production of crops in alleviating the food crisis and it has also increased nitrogen consumption. Constantly increasing demand for increased nitrogen application to achieve required rice production is an important problem in rice. For majority of the cereal crops, only 30-40% of the applied nitrogen is utilized and remaining is lost to the newlineenvironment, indicating the importance of environmentally sustainable agriculture. To achieve the increased rice yields with newlineenvironmental safety, developing genotypes with promising yield under low nitrogen conditions is crucial, which can further prevent nitrogen losses and promote environmentally sustainable agriculture. newlineIn the present study 107 rice genotypes were screened at field conditions under low (native soil nitrogen / without externally added nitrogen) and recommended nitrogen (100kg/ha) levels. Total of 10 newlinegenotypes were selected for photosynthetic characters, nitrogen metabolic enzymes and antioxidant enzymes studies based on filled grain weight per plant under low nitrogen conditions.