Softwood cutting propagation of three Polygonella wildflower species native to Florida.

摘要

Largeleaf jointweed (Polygonella macrophylla), October flower (Polygonella polygama), and sandhill wireweed (Polygonella robusta) are wildflowers that exhibit good form and showy flower displays within their natural growing environments. To broaden production and landscape use when seed is not available, asexual propagation has been explored as a potential alternative to seed produced transplants. Softwood cuttings of each Polygonella species were collected from natural areas in Florida to (1) evaluate the effectiveness of various concentrations of K-IBA on rooting, and (2) determine the effect of propagation substrates on rooting success. The basal portion (1 cm) of terminal stem cuttings (8 cm) prepared from current season growth were treated with one of four concentrations (0, 1,000, 2,500, or 5,000 mg l-1) of K-IBA using the quick-dip method (5 s) prior to planting in Fafard 3B or a mixture (50:50 by volume) of horticultural grade perlite and medium grade vermiculite and placed on greenhouse benches with intermittent mist. Approximately 7 weeks after planting, cuttings were evaluated for: rooting, root number, and length of the longest root. Rooting percentages of 80% or greater were achieved with K-IBA at concentrations of 1000 to 5000 mg l-1. Little or no difference in rooting percentage or root number was evident between the two propagation substrates.