Rejuvenation of E. brachyphylla and determination of miR156 and miR172 expression. (a) Sections from a 7-month-old tree, which had lost its rooting ability, rejuvenated in tissue culture (TC). (b) Rooting percentage in E. brachyphylla plants at different ages. (c,d) Analysis of miR156 and miR172 expression: (c) quantitative analysis of the gels in (d). Rooting was determined using 50 cuttings and RNA was prepared from 30 cuttings from each age.