Table 2. Effect of calcium concentration during root induction on the growth of acclimated peony plants after cold treatment.

Calcium concentration (mM)	Fresh weight (g)	Number of buds	Root length (cm)	Number of primary roots	Maximum root diameter (mm)
3	3.3±1.1	2.0±0.8	30.7±6.8	6.0±4.5	4.0±1.3
6	5.9±2.8	3.1±1.1	28.8±4.4	8.9±4.2	5.5±2.1
p-valuea	0.019	0.041	0.506	0.189	0.127

After the peony plantlets (PLKD2: Ca²⁺ 3 mM or 6 mM) were cultivated in a closed greenhouse (20°C with the same conditions as Table 1) for 181 days, the aerial parts of the plants were removed and cold treated at 4°C for 198 days. After cold treatment, plant fresh weight, number of buds, root length, number of primary roots, and maximum root diameter were measured. The values represent the mean±SD of at least seven replicates. ^a Student’s t-test.