Fig. 1. Fine mapping of qFLW11 in near-isogenic lines (NILs) and functional analysis of FLW11. A, Fine mapping of qFLW11 on chromosome (Chr.) 11 in NILs (H1-H8). NPB, Nipponbare; Y476, Wild rice (Oryza rufipogon). FLW, Flag leaf width. B, Phenotypes (above) and FLW (below) of NIL-FLW11Y476-90, NIL-FLW11Y476-94, NIL-FLW11NPB-81, and NIL-FLW11NPB-111 (NIL-FLW11Y476-90 and NIL-FLW11Y476-94 lines containing the Y476 fragment in the qFLW11 interval, while NIL-FLW11NPB-81 and NIL-FLW11NPB-111 lines containing the NPB fragment in the qFLW11 interval). Scale bars, 10 cm (above) and 2 cm (below). C, Phenotypes of wild type Zhonghua 11 (ZH11) and knockout mutants (FLW11-KO-1 and FLW11-KO-2) at the heading stage. Scale bar, 30 cm. D and E, FLW of ZH11, FLW11-KO-1, and FLW11-KO-2. Scale bar, 1 cm. In E, data are mean ± SD (n = 10). Differences between ZH11and FLW11-KO were analyzed using the Student’s t-test. ns, P > 0.05; *, P < 0.05; **, P < 0.01. F, Cross section of leaves of ZH11, FLW11-KO-1, and FLW11-KO-2 under blue fluorescence with a light-emitting diode wavelength of 470 nm. Scale bars, 200 μm. The red arrow indicates the small vascular bundle. G-I, The number of large vascular bundles (G), distance between large vascular bundles (H), and the number of small vascular bundles (I) for ZH11 and FLW11-KO (FLW11-KO-1 and FLW11-KO-2). Data are mean ± SD (n = 10). Differences between ZH11 and FLW11-KO were analyzed using the Student’s t-test. ns, P > 0.05; *, P < 0.05; **, P < 0.01. J, High-density gene-based association analysis and linkage disequilibrium heat map of local Manhattan map, around the peak on chromosome 11. K, Haplotype analysis and genetic structure map of FLW11. L and M, FLW (L) and yield per plant (M) in different FLW11 haplotypes. Data are mean ± SD (n > 50). Significant differences among Hap1, Hap2, and Hap3 were determined by one-way ANOVA followed by Tukey’s post hoc test. ns, P > 0.05; *, P < 0.05; **, P < 0.01.