Figure 1.

Successive Changes in Morphology and Anatomy of Developing LJs

(A–E) Seedling morphology at five stages during LJ development (S1–S5). col, coleoptile; il, incomplete leaf (the first true leaf); fcl, first complete leaf (the second true leaf); LJ, lamina joint; bl, blade; sh, sheath; DAG, days after germination. Scale bars, 0.5 cm.

(F–J) LJ morphology of the first complete leaf at five stages shown in (A-E). The left panel, the phenotype of LJ region in the first complete leaf; the right panel, the magnified view of LJ in the first complete leaf. LJ, lamina joint. Scale bars, 0.2 mm.

(K–T) Cross sections (K–O) and longitudinal sections (P–T) of the LJs in the first complete leaves at five stages. lg, ligule; vb, vascular bundle; sc, sclerenchyma; ae, aerenchyma; pc, parenchyma; ab, abaxial side; ad, adaxial side; ld, lignin deposition. m1, the region between the adaxial sclerenchyma and the adaxial epidermis in a cross section; L1, the region between the abaxial and the adaxial epidermis in a maximum longitudinal section. The upper images are magnified views of the regions indicated in black boxes. Scale bars, 100 μm.

(U) Lengths of LJs, blades, and sheaths of the first complete leaves at five stages (n = 10).

(V and W) Cell layers (V) and cell width (W) in the L1 regions (P–R). (n = 10).

(X and Y) Cell layers (X) and cell width (Y) in the m1 regions (M–O). (n = 10).

Data are the means ± standard deviation (SD). Significance of all comparisons was determined using Student's t test with ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001, and ns indicates no significance. See also Figure S1.