Multi-Trait Characterization and Selection of Elite Wild Kiwifruit (Actinidia spp.) Germplasm from the Dabie Mountains of Hubei, China

Wild kiwifruit germplasm can broaden breeding pools through complementary fruit-quality and stress-response traits. The Hubei Dabie Mountains contain heterogeneous habitats, but coordinated evaluation of their wild Actinidia resources remains limited. Taxonomy and ploidy were determined for 117 accessions from eight sites spanning 170–1730 m. Nine descriptive fruit traits and detached-leaf responses to bacterial canker and heat were assessed in 41 fruiting accessions. Bacterial canker response was assessed using Pseudomonas syringae pv. actinidiae (Psa), and heat response using maximum photosystem II quantum efficiency (Fv/Fm) after 47 °C treatment. Seven fruit-quality traits were measured in 27 accessions with normally ripened fruit. Three taxa were identified: A. chinensis, A. polygama, and A. chinensis var. deliciosa. Diploid, tetraploid, and hexaploid cytotypes were detected. Shannon–Wiener indices for descriptive traits ranged from 0.26 to 1.64. Twenty-three accessions were classified as highly or moderately resistant to Psa. Heat screening classified 23 accessions as heat tolerant, 16 as moderately heat tolerant, and two as heat sensitive. Fruit-quality coefficients of variation ranged from 12.92% to 120.41%. Fruit-quality ranking followed by Psa screening identified MC-021, MC-026, YS-031, YS-037, and YS-038 as candidate elite germplasm. These accessions are priorities for conservation and further breeding evaluation.