Revisiting development and physiology of wild rice relatives for crop improvement and climate resilience

Abstract

Increasing rice yield and productivity under changing climatic conditions is imperative for sustainable food security, given rice is a major staple crop around the world. Natural variation in crop plants, including wild relatives, offers remarkable genetic variability to explore the desirable developmental and physiologic traits for crop improvement. Wild relatives of rice, with distinct developmental and physiologic features compared to cultivated varieties, are the potential genetic and genomic resource for rice yield increases under changing climate. A thorough genetic basis of rice developmental and architectural changes during domestication is now established with the identification and characterization of domestication genes. Photosynthetically efficient wild rice accessions, with desirable developmental, physiologic, and metabolic traits, have been identified in recent years that could be instrumental for rice improvement. While several abiotic and biotic stress-tolerant wild relatives of rice along with the associated genetic loci have been identified over the years, a comprehensive insight into the desirable developmental and physiologic attributes of the wild rice is limited. Moreover, the usage of wild rice is not streamlined in rice-improvement programs due to genetic and genomic constraints. In this review, we summarize the desirable developmental and physiologic features of wild rice species that can be exploited for combining yield increases with climate resilience in rice-improvement programs.