Plant genotype, juvenility and mechanisms of inhibition of rooting Persoonia virgata R. Br. Cuttings

Abstract

Summary. Persoonia virgata is an endemic shrub of Australia that is being bush-harvested for its foliage and sold on the domestic and export flower markets. The limiting factor to the cultivation of many desirable Persoonia species has been the extreme difficulty in developing a reliable propagation system. This study investigated the effects of cutting type, maturity of the stock plant, and genotype, on the rooting of P. virgata cuttings. It was found that juvenile cuttings rooted significantly better than mature cuttings. Some juvenile seedling genotypes yielded no rooted cuttings, whereas others produced up to 90% rooting. No anatomical barrier to root formation was discovered. High performance liquid chromatography showed differences in the abundance of unidentified compounds in cuttings, related to season and to genotypic differences in rooting abilities. A possible seasonal rooting inhibitor was present in some genotypes. The potential for selection of genotypes with improved rooting ability has been demonstrated.