The ex vitro rooting of blueberry (Vaccinium corymbosum L.) microcuttings

A growing demand for blueberry fruit has necessitated the development of an efficient propagation method of this species that would provide large quantities of planting material. The aim of this study was to evaluate the effects of auxin indole-3-butyric acid (IBA 50 mg dm⁻³), the commercial rooting powder Rhizopon containing 1% IBA, and salicylic acid (50 mg dm⁻³) on the in vivo rooting of microcuttings of Vaccinium corymbosum ‘Bluecrop’ and ‘Duke’. The contents of chlorophyll a + b, soluble proteins, free amino acids, as well as total soluble and reducing sugars were determined in rooted cuttings. All of the treatments increased the degree and percentage of rooting in the cuttings of both cultivars. While improving rhizogenesis in blueberry, salicylic acid did not perform as a cofactor of the auxin IBA. Foliar applications of IBA or salicylic acid (SA) increased the contents of soluble proteins, free amino acids and sugars, but no effects on chlorophyll levels were observed.