Fig. 6: Functional analysis of HAN2 regulation on chilling tolerance at rice booting stage.

a Left and right panels show 93-11 and NIL-HAN2^NPB plants before and after chilling treatment, respectively. Bar = 3 cm. b Seed setting rates of 93-11 and NIL-HAN2^NPB under normal conditions. Data are shown as mean ± SD (n = 20 biological replicates). c Seed setting rates of 93-11 and NIL-HAN2^NPB under chilling conditions. Data are shown as mean ± SD (n = 15 biological replicates). d Chilling tolerance phenotype of WT and han2-2 plants at the booting stage. Left and right panels show WT and han2-2 plants before and after chilling treatment, respectively. Bar = 3 cm. e Seed setting rates of WT and han2-2 under normal conditions. Data are shown as mean ± SD (n = 15 biological replicates). f Seed setting rates of WT and han2-2 under chilling conditions. Data are shown as mean ± SD (n = 15 biological replicates). g Auxin content in spikelets of 93-11 and NIL-HAN2^NPB after treatment at 19 °C. Data are shown as mean ± SD (n = 4 biological replicates). h OsMAP1/OsMPK3 expression in spikelets of 93-11 and NIL-HAN2^NPB at various time points under 19 °C treatment. Data are shown as mean ± SD (n = 3 biological replicates). i Trehalose content in spikelets of 93-11 and NIL-HAN2^NPB before and after 19 °C treatment. Data are shown as mean ± SD (n = 4 biological replicates). j Auxin content in spikelets of WT and han2-2 before and after 16 °C treatment. Data are shown as mean ± SD (n = 3 biological replicates). k OsMAP1/OsMPK3 expression in spikelets of WT and han2-2 at various time points under 16 °C treatment. Data are shown as mean ± SD (n = 4 biological replicates). l Trehalose content in spikelets of WT and han2-2 before and after 16 °C treatment. Data are shown as mean ± SD (n = 3 biological replicates). Statistical significance in (b, c, e–l) was evaluated using a two-tailed Student’s t-test; P-values are indicated. Source data are provided as a Source Data file.