Characterization and Propagation of Paʻuohiʻiaka (Jacquemontia sandwicensis A. Gray) for Potential Use as a Hanging Basket Plant

Abstract

The use of native Hawaiian plants as ornamentals has increased in the last 28 years. Despite active promotion, efforts to expand selections for horticultural use have been minimal. Pa‘uohi‘iaka (Jacquemontia sandwicensis A. Gray) is a prostrate-growing, endemic vine commonly found in coastal areas. In the wild, morphological variation exists but efforts to collect and characterize these variations for hanging basket use have been limited. To develop the use of pa‘uohi‘iaka as a hanging basket plant, six accessions were collected, characterized and assessed for rooting response. Morphological characterization indicated that each accession has its own unique set of qualitative and quantitative characters. Principal component analysis identified leaf shape, leaf length, adaxial and abaxial stem color, length of internodes and length of lateral branches, flower color and number and flowers as important characters that contribute to the variation of the six accessions. Cluster analysis revealed three distinct groups. Lyon Arboretum, Puhala Bay and South Point were selected for further evaluation because of their shorter internodes and lateral branching. Rooting response was associated with high leaf retention and longer cutting length (i.e. four nodes). Leaf retention was negatively affected by leaf pubescence. Due to poor rooting and survival of stem cuttings after transplanting, the South Point accession was dropped for further evaluation.