Rice research in the high-throughput sequencing era: Genomic breeding Rice breeding for better health

Abstract

Rice [ Oryza sativa L.] is the most important cereal crop belongs to the family Poaceae (Grass) which provide staple food for half of the World's population (>3.3 billion). This staple food grain (rice) supplies the main energy resource providing 40-75% of the daily calorie intake to the world's poor people. It is equ ivalent to the proposition that 'Rice is life' in Asian continent because 90% people dependent on for their sustainable livelihood. Simultaneously Asia is considered as 'Rice Basket' because it produces 90% of the world's production (662 million tons, paddy rice, Mt). Total world production was 729 Mt from '154.3 million hectares with productivity of 4.1 tons/hectare (t/ha) in 2012 of which 662 million tons produced by Asian countries. Rice production has been doubled in the recent decades (1960s-1990s) during the tim~ of Green Revolution (1960s) primarily as the result of genetic improvement. It was factual that the varieties released in the· last 30 years in the farmers field, had a narrow genetic base in-spite of high genetic diversity prevailed in the rice germplasm, and yield enhancing capacity has reached to plateau. We need more production of rice to feed 9 Billion people in 2050. Breeder could manage the yield increase over released varieties through genetic gain by combining the yield related genes/QTLs from various genetic resources of rice germplasms either from cultivated local landraces or from wild varieties. Germplasm diversity is the mainstay for crop improvement and genetic dissection of complex traits. Rice germplasm shows tremendous genetic diversity in both within the species and among the varietal groups. This genetic diversity may be associated with the diverse allel~ of important traits and can be exploited to introgress these traits using knowledge of molecular breeding techniques such as marker assisted breeding (MAB) or marker assisted selection (MAS). The Next Generation Sequencing based technology is used for whole genome analysis to unveil the genetic and genomic infor'mation pertaining to important traits for advancing the molecular breeding procedures to increase the production. That ultimately leads to the development of genomic breeding and genomic selection to accelerate the breeding process.