Genetic, Molecular and Genomic Basis of Rice Defense against Insects

Rice is the world's most important staple crop, feeding more than half of the world's population. Insects and other arthropods present an important constraint in rice production. This paper begins with an introduction to major insect pests of rice and their impact, followed by a description of some of the approaches currently used in insect management programs of rice. Then the paper reviews the current understanding of rice defense mechanisms against insects at the levels of genetics, molecular biology and genomics. Some loci that confer resistance to specific type of insects have been and continue to be discovered hand-in-hand with rice breeding programs. Various natural defense strategies of rice against insects illustrate the complexity of rice defense mechanisms that have evolved during the long co-evolutionary history of rice and insects. The molecular mechanisms underlying these natural defenses continue to be elucidated. The availability of the rice genome sequence in conjunction with cutting-edge genomic technologies, including transcriptomics, proteomics and metabolomics, provides scientists an unprecedented opportunity to unravel the functions of rice defense genes against insects at a high-throughput manner. The knowledge and molecular tools developed through these studies will undoubtedly facilitate the development of novel rice varieties with enhanced insect resistance.