Fig. 4

Growth of A. alba x A. numidica (a) and P. nigra (b) ET lines during 28 days and 35 days, after recovery from LN, respectively. C—Control = fresh, non-cryopreserved ET; S—ET treated with sucrose and SSG—ET treated with sucrose and silica gel (only P. nigra measured); LN—ET after storage in LN. Mean ± SE; ANOVA with Tukey’s test; ns p > 0.05; *: p ≤ 0.05; **: p ≤ 0.01; ***: p ≤ 0.001