Figure 2. Overexpression of Ncl in transgenic lines enhanced salt tolerance.

(a) Real-time quantitative RT-PCR analysis of Ncl expression levels in the transgenic soybean lines and control materials after treatments with 100 mM NaCl for 24 hours in a hydroponic condition. 54-1-1, 34-2-7, 20-1-4, and 16-1-8 are T₂ 35S:Ncl transgenic lines. Kariyutaka: wild-type soybean cultivar. GFP is 35S:GFP transgenic line (T₆). NILs18-T and NILs18-S are tolerant and sensitive near isogenic lines. Values represent means from three biological replicates. (b,c) Leaf SPAD values and shoot dry weight for the transgenic lines after treatments with 100 mM NaCl for approximately three weeks in a hydroponic condition. (d) Na⁺, K⁺, and Cl⁻ leaf contents for the transgenic lines after treatments with 100 mM NaCl and 0 mM NaCl (Control) for approximately three weeks in a hydroponic condition. (e) Comparison of salt tolerance between 35S:Ncl plants and null plants of the T₂ transgenic line 20-1-4. Data are expressed as means ± s.d. **indicate significant difference at P < 0.01 levels versus from Kariyutaka (wild-type) (Dunnett’s multiple comparison test).