The acclimation of introduced Wild Peony in Chengdu

To evaluate summer performance and off-site cultivation adaptability of three wild peony species in Chengdu.5-6-year-old individuals of Paeonia rockii, P. decomposita and P. delavayi were planted at the Tianpeng Peony Conservation and Development Center in Chengdu. Growth, phenology and leaf physiological responses (MDA, SOD, CAT, POD) were monitored under summer high-temperature conditions and compared with local cultivar 'Jinyao Lou'.Under prolonged summer heat, leaf MDA increased most in P. decomposita, then P. delavayi, and least in P. rockii. P. decomposita exhibited declins in SOD and CAT, with POD showing a transient increase followed by a decrease; P. delavayi and P. rockii exhibited decreases in SOD, CAT and POD, with P. rockii declining more slowly and not differing significantly from 'Jinyao Lou'. Phenologically, P. decomposita and P. rockii advanced flowering relative to their native sites; P. rockii flowered earlier, with more flowers and a longer bloom than P. decomposita. P. delavayi showed earlier germination but delayed bud formation and shortened flowering.After three wild peonies were introduced to the experimental field, their heat tolerance was shown as P.rockii > P.delavayi > P.decomposita. Among them, the heat tolerance of P.rockii showed no significant difference from that of the local 'Jinyao Lou'. Field cultivation showed that P.rockii > P.decomposita > P.delavayi. The introduction adaptability of the P.rockii is good. For the other two species, cultivation and management measures need to be taken after introduction to reduce the damage suffered by the peonies in order to improve their adaptability in the Chengdu.