2019 ASHS Annual Conference

A greenhouse study was conducted to assess the relative salt tolerance of eight woody ornamentals: Itea virginica ‘Scentlandia’, Juniperus communis ‘Gold Cone’, Loropetalum chinense ‘Jazz Hands Bold’, Aronia melanocarpa ‘Low Scape Hedger’, xPyracomeles ‘Juke Box’, Ilex glabra ‘Shamrock’, I. verticillata ‘Berry Poppins’, and I. x meserveae ‘Castle Spire’. Rooted cuttings received from a commercial company were transplanted to 2.6 L containers filled with Metro-mix and grown in the greenhouse for one month. Plants were then irrigated with nutrient solution at electrical conductivity (EC) of 1.5 dS/m or nutrient-solution based saline solution at EC of 4.0 dS/m (EC 4) or 8.0 dS/m (EC). Four weeks after saline solution treatment, the visual score of plants in EC 8 was the highest in I. glabra ‘Shamrock’, followed by I. x meserveae ‘Castle Spire’ and J. communis ‘Gold Cone’, while L. chinense ‘Jazz Hands Bold’ and A. melanocarpa ‘Low Scape Hedger’ had the lowest scores with severe foliar salt damage. Plants in EC 4 had minimum foliar damage except for ‘Jazz Hands Bold’, A. melanocarpa ‘Low Scape Hedger’, and xPyracomeles ‘Juke Box’. Based on leaf area and dry weight, salinity treatment did not impact the I. glabra ‘Shamrock’, I. x meserveae ‘Castle Spire’, and J. communis ‘Gold Cone’. The growth of I. verticillata ‘Berry Poppins’ was only reduced in the EC 8 treatment. In summary, among the eight species, I. glabra ‘Shamrock’, I. x meserveae ‘Castle Spire’, and J. communis ‘Gold Cone’ were relatively tolerant to elevated salinity, while L. chinense ‘Jazz Hands Bold,’ A. melanocarpa ‘Low Scape Hedger’, and xPyracomeles ‘Juke Box’ were less tolerant.