LATERAL FLORET 1 induced the three-florets spikelet in rice

Significance In cereal crops, the number of florets in a spikelet is an important factor affecting the grain number per panicle and then the grain yield. In wild-type rice, one spikelet produces one fertile floret. This study characterized a gain-of-function mutant lateral florets 1 ( lf1 ) in rice. In lf1 , the spikelet developed lateral florets with proper floral organ identities in the axil of the sterile lemma, showing that the rice spikelet has the potential to restore the “three-florets spikelet” which may have existed in ancestors. Therefore, it provides strong evidence supporting the three-florets spikelet hypothesis and presents a prospect for increasing grain number per panicle by breeding rice with three-floret spikelets.