Thirty-one spathiphyllum (Spathiphyllum Schott.) cultivars were evaluated for flowering response following treatment with gibberellic acid (GA3). Greenhouse-grown plants were treated once with 250 mg·L-1 (ppm) GA3 applied as a foliar spray. Within 16 weeks after treatment all GA3-treated plants had flowered but none of the untreated controls produced flowers. `Vickilynn' (14.1 flowers/plant after 16 weeks), `Piccolino' (12.8), `Mascha' (12.6), `Chris' (11.7), `Alpha' (11.7), and `Daniel' (11.0) produced significantly more flowers than other cultivars. The cultivars producing the fewest flowers per plant after 16 weeks were `Sierra' (2.5), `S1008' (3.2), `Rica' (3.4), `Sonya' (4.3), `Vanessa' (5.1), `S18' (5.5) and `S4002' (5.6). `Alpha,' `Textura,' `Daniel,' `Mascha,' `S1007', and `Showpiece' had significantly better flower quality. `S1008,' `Codys Color', and `Petite' had poor flower quality. `Mascha' was the earliest cultivar to bloom producing maximum flower counts during weeks 9 to 10 after treatment while `Vanessa' was the latest to flower with peak bloom occurring 15 to 16 weeks after treatment. Most cultivars reached peak bloom at 11 to 13 weeks after treatment. Results indicate sufficient genetic variability in spathiphyllum flowering response to GA3 treatment exists to permit cultivar selections based on differences in flowering time, number of flowers and flower quality.
R.J. Henny, T.A. Mellich and D.J. Norman
Richard J. Henny, Jianjun Chen and T.A. Mellich
Jianjun Chen, R.J. Henny, T. Mellich, R.D. Caldwell and C.A. Robinson
Anthurium cultivars are being produced primarily as cut-flower plants. Whether Anthurium can be used as a flowering interiorscape plant is not well documented. Therefore, five finished Anthurium cultivars were evaluated in interior acclimatization rooms under two light intensities provided by cool-white fluorescent lamps for 12 hours daily: 16 mmol·m–2·s–1 (low light) and 48 16 mmol·m–2·s–1 (high light). Temperature of the rooms was maintained at 24 °C with a relative humidity of 60%. Total number of open flowers and number of senesced flowers were recorded weekly over 5 months. In addition, plant canopy height and width and total number of leaves were measured monthly. Number of open flowers per week ranged from 1.4 to 4.7 under low light and 2.4 to 6.3 under high light. The cultivar Red Hot showed the best performance with a weekly average flower count of 4.7 under low light and 6.3 under high light. All cultivars continued to produce new leaves, ranging from one to five per month under low light and two to five leaves under high light. Leaves were dark green and shiny under the interior conditions. Growth index of `Red Hot' increased 31% under low light and 20% under high light. Results from this study demonstrate that Anthurium can continue to grow and produce flowers under interior environmental conditions. Variation among cultivars indicates that genetic potential exists for selecting improved cultivars based on interior performance.
R.J. Henny, J. Chen, T.A. Mellich and M.S. Brennan
D.J. Norman, R.J. Henny, J.M.F. Yuen and T.A. Mellich
Commercially grown cultivars of Syngonium (Araceae) are very susceptible to Myrothecium leaf spot (incited by Myrothecium roridum Tode ex Fr.). Therefore, cultivation of Syngonium requires rigorous sanitation and frequent applications of fungicides for disease control. The goal of this research was to identify species and noncultivated accessions of Syngonium resistant to Myrothecium leaf spot. Five commercial cultivars and 30 accessions, comprising 16 different Syngonium species, were screened for resistance to M. roridum. All five commercial cultivars were susceptible to M. roridum. However, seven species (S. neglectum, S. wendlandii, S. dodsonianum, S. erythrophyllum, S. chiapense, S. dodsonianum, and S. angustatum) showed the highest resistance, as did two noncultivated accessions of S. podophyllum. The information on disease resistance for these species and accessions will be useful in future breeding work.