Conventional and new breeding approaches to enhance grain yield in rice

Abstract

From a ship-to-mouth existence at the time of its Independence, India became a food sufficient country due to the research and policy interventions during the green revolution era and in the last six decades. The country witnessed a phenomenal increase in the production and productivity of rice and wheat and presently the country is exporting significant quantities of rice. However, there are multiple challenges in ensuring food and nutritional security through rice in the coming decades including a rapidly changing climate and a plateauing of rice yields has been witnessed in the last two decades in many rice growing countries across the world including India. It is therefore imperative to enhance rice productivity and production through application of modern tools of science. This review traces the developments related to rice research and yield improvement over the last six decades and discusses about the conventional and modern approaches to enhance grain yield in rice. These approaches include pre-breeding, wide-hybridization, new plant type/ideotype breeding, heterosis breeding, marker and genomics-assisted breeding, haplotype-based breeding, transgenic breeding and genome editing.