Length, diameter and wall thickness of the first and second internode at the base of the stem of Rht12 dwarf and tall genotypes with and without GA3 treatment in the three experiments.

Note: AS: autumn-sown experiments; SS: spring-sown experiments. LT is internode length; DI is internode diameter at the mid-point; WT is wall thickness. All data are means ±SD of each genotype. Different letters within columns indicate statistically significant differences (P