ROOT REGENERATION ON INCUBATED LIGNIFIED ROOTS OF KURUME AZALEAS IS CORRELATED TO TOLERANCE TO ENVIRONMENTAL STRESS

Kurume azaleas are susceptible to drought and high temperature stress.
A method was studied to identify stress tolerant genotypes based on their ability to regenerate new secondary roots during incubation of lignified root cuttings.
The root regenerating potential (RRP) was calculated from characteristics of root regeneration during incubation of 5 cm-long lignified root cuttings obtained from young azalea ‘Chikushibeni’ plants during the winter or spring season.
Lateral root regeneration was best during incubation at 22°C for 20 to 30 days after cuttings were immersed in 25 mg L^-1 NAA solution for 4 hours at room temperature.
The stress tolerance of eight cultivars from four Rhododendron groups was evaluated by this method and RRP ratings generally corresponded with an evaluation based on azalea cultivar growth in the field.
It was concluded that RRP could be used to evaluate environmental stress tolerances of azalea groups early and simply without long term field study.

XXVII International Horticultural Congress – IHC2006: International Symposium on Ornamentals, Now!

M. Yamashita, A. Okamoto

Rhododendron Kurume group, root regenerating potential

https://doi.org/10.17660/ActaHortic.2008.766.31