Paleo-Green Revolution for rice

Abstract

A central element of the Green Revolution was the widespread adoption of semidwarf rice cultivars (SRCs) that more than doubled worldwide rice production (1). The high-yield potentials of modern SRCs are attributed primarily to their improved harvest index, lodging resistance, and responsiveness to high inputs (primarily nitrogen and water) (1–3), contributing to their adoption in irrigated areas that occupy 57% of world rice lands (4). The short stature of SRCs is caused by sd1 , a mutant allele in the gene encoding a key enzyme (gibberellin 20-oxidase) functioning in biosynthesis of the plant hormone gibberellic acid (GA) that greatly reduces content of the bioactive molecule GA1 (5, 6). In PNAS, Asano et al. (7) show that the SD1 locus (where the sd1 mutation resides) has been a target of human-mediated selection since prehistoric times. In a population of backcross inbred lines from a cross between an Oryza sativa paddy rice (subspecies japonica ) variety Nipponbare and an upland rice (ssp. indica ) variety Kasalath, a quantitative trait locus, qCL1 , accounts for 20.9% of phenotypic variation in culm length. Study of 5,000 plants segregating at the qCL1 locus shows … [↵][1]2To whom correspondence should be addressed. E-mail: paterson{at}plantbio.uga.edu. [1]: #xref-corresp-1-1