Fig. 3: OsNLP4^indica transgenic plants exhibit increased yields and NUE.

a Growth phenotype of representative DJ, OsNLP4 ^japonica transgenic plants (gDJ-1, gDJ-2), and OsNLP4^indica transgenic plants (g9311-1, g9311-2) at the maturing stage in a field trial at Hefei in 2023. Scale bar = 8.0 cm. Tiller number per plant (b), actual yield per plot (c), and NUE (d) of DJ, gDJ-1, gDJ-2, g9311-1, and g9311-2 in the field trial. e Phenotypes of DJ, gDJ-1, gDJ-2, g9311-1, and g9311-2 grown in hydroponic medium with different nitrate concentrations for 18 days. Scale bar = 2.0 cm. f Biomass of the plants under different nitrate conditions, as shown in (e). g Growth phenotype of representative DJ, OsNLP4^japonica transgenic plants (gDJ-1), and OsNLP4^indica transgenic plants (g9311-2) at maturing stage in the field under different N conditions (Changxing, Zhejiang Province, China). LN: 90 kg urea/ha, NN: 180 kg urea/ha, HN: 360 kg urea/ha. Scale bar = 8.0 cm. Actual yield per plot (h), and NUE (i) of DJ, gDJ-1, and g9311-2 in the field trial. j Phenotypes of 2-week-old wild-type Arabidopsis (Col-0), OsNLP4^japonica transgenic plants (OsNLP4^DJ-1, OsNLP4^DJ-2), and OsNLP4^indica transgenic plants (OsNLP4⁹³¹¹-1, OsNLP4⁹³¹¹-2) grown in soil. k Shoot fresh weight of the plants under the conditions shown in (j). l Hierarchical clustering analysis was conducted on expression profiles of 20 N metabolism-associated genes in Col-0, OsNLP4^japonica transgenic plants (OsNLP4^DJ-1), and OsNLP4^indica transgenic plants (OsNLP4⁹³¹¹-1). Transcriptome profiling was performed using 16-day-old Arabidopsis seedlings grown on MS medium. The heatmap displays log₂-transformed expression ratios of N metabolism marker genes. Data points meeting statistical significance thresholds (P < 0.05) were selected for visualization using a graduated color scale. FPKM (fragments per kilobase of transcript per million mapped fragments) values represent normalized transcript abundance. Values represent the means ± SDs (n = 16 plants for b, f and k, n = 4 replicates, 80 plants per replicate for c, d, h, and i, and n = 3 replicates for l). The different letters above the bars denote significant differences (P < 0.05) according to a two-sided Duncan’s multiple range test. Source data are provided as a Source Data file.