A two-locus interaction causes interspecific hybrid weakness in rice

Citations Over TimeTop 10% of 2014 papers

Abstract

Reproductive barriers perform a vital role during speciation. Hybrid weakness, the poorer development of hybrids compared with their parents, hinders gene exchange between different species at the postzygotic stage. Here we show that two incompatible dominant loci (Hwi1 and Hwi2) involving three genes are likely to determine the high temperature-dependent expression of hybrid weakness in interspecific hybrids of rice. Hwi1 comprises two leucine-rich repeat receptor-like kinase (LRR-RLK) genes, 25L1 and 25L2, which are specific to wild rice (Oryza rufipogon) and induce hybrid weakness. Hwi2, a rare allele that is predominantly distributed in indica rice (Oryza sativa), encodes a secreted putative subtilisin-like protease. Functional analysis indicated that pyramiding of Hwi1 and Hwi2 activates the autoimmune response in the basal nodes of hybrids, interrupting root formation and then impairing shoot growth. These findings bring new insights into our understanding of reproductive isolation and may benefit rice breeding.

Related Papers

• → Australian Oryza: Utility and Conservation(2009)68 cited
• → Identification and characterization of Australian wild rice strains of Oryza meridionalis and Oryza rufipogon by SINE insertion polymorphism(2005)20 cited
• → Chronology of ancient Dongxiang wild rice (Oryza rufipogon Griff.), and the morphologies of grains, double-peaked phytoliths, and starch, in the middle Yangtze river region, China(2017)6 cited
• → Intra- and interspecific sexual isolation in two sibling species ofDrosophila: D. ananassaeandD. pallidosa(2020)2 cited
• Similipal biosphere reserve: Home of cultnated and wild Oryza species(2000)