Anthuriums are Hawaii’s top cut flower with its sales valued at USD1.6 M in 2022. It is an important floriculture crop as it is both used as cut flower and foliage. Development of new genotypes allows the growers in Hawaii to produce new cultivars desired by the market. The University of Hawaii anthurium breeding program has identified new selections to field test with commercial growers. In order to do so, the breeding program propagates these selections to send to growers. Recently the use of bioreactors, such as RITA® on ‘New Pahoa Red’, resulted in three times more shoot production than in traditional flasks placed on a platform shaker. Shoot and root production and axillary bud mass volume of three new selections, UH2647, UH2651, and UH2652, were compared against the control ‘New Pahoa Red’. Ten nodes of each genotype were placed in a RITA® bioreactor, and replicated five times in a completely randomized design. Nodes were cultured in liquid medium consisting of 0.3MS, 0.1 mg l-1 BA, 15% coconut water, 20 g l-1 sucrose, and 1 ml l-1 NaSiO3. The plants were cultured in the bioreactors for 1.5 months, and then removed to obtain the number of shoots, roots, and axillary bud mass volume. Primary shoots were excised and transferred to 0.3 MS, 15% coconut water, 20 g l-1 sucrose, and solidified with 6 g l-1 Gelzan® to promote axillary bud growth and shoot development. The pH for all media was adjusted to 5.8. One month later, shoots (~0.5 cm in height) were excised from the axillary bud masses. Shoot counts excised after initial culture in the liquid medium and after placement in the shoot development solid medium were analyzed using one-way ANOVA on R studio. Axillary bud mass volume and root number were analyzed. UH2647 significantly produced more shoots than UH2652 and ‘New Pahoa Red’, while UH2651 was not different from any genotype. UH2647 also had the highest average axillary bud mass volume. UH2651 and UH2652 produced significantly more roots than the control. Knowing the genotypic differences in shoot production will assist propagation facilities in developing guidelines to schedule production of individual genotypes.
