Yellow bracteantha or strawflower; Lucky Lemon Cream and Lucky Peach Sunrise lantana; and Cascadias Pink and Suncatcher Pink petunia. All were planted in soilless media (Sunshine Mix #1; SunGro Horticulture, Bellevue, WA) because of the lack of
Shannon E. Beach, Terri W. Starman, Kristen L. Eixmann, H. Brent Pemberton and Kevin M. Heinz
Shannon E. Beach*, Terri W. Starman and H. Brent Pemberton
Bracteantha bracteata (Vent.) Anderb. & Haegi (bracteantha) is a vegetative annual produced as a 12.7-cm potted plant in 6 weeks of greenhouse production. A dense leaf canopy produced with a conventional constant-feed fertilization regime (300 mg·L-1 20N-4.4P-16.6K) caused increased disease pressure and lower leaf chlorosis during greenhouse production. During shelf life, lower leaves of plants con-tinued to become chlorotic. The objective was to decrease leaf area and prevent lower leaf chlorosis without affecting harvest time, plant quality or shelf life of two cultivars of three series of bracteantha. The first experiment was to reduce the rate of fertilizer two weeks prior to harvest. Treatments were no fertility reduction (300 mg/liter), 50% reduction (150 mg/liter), and 100% reduction (0 mg·L-1). At harvest, plants were evaluated for shelf life in a growth room at 21.1 ± 1.3 °C and 6 μmol·m-2·s-1 PPF. Five cultivars in the 100% fertility reduction treatment had decreased height and/or width index at harvest and three cultivars maintained higher postharvest quality ratings compared to the other treatments. Separately, the effect of the duration of fertilization was evaluated by terminating fertilization at weekly intervals (0-6 weeks) throughout production. Ceasing fertilization two to three weeks prior to harvest produced plants with lower leaf area without affecting flower number. In another experiment, thidiazuron (TDZ) as a foliar spray at 0, 0.1, 0.5, and 1.0 mg·L-1 was applied to decrease lower leaf yellowing. SPAD-502 chlorophyll meter readings of lower leaves were increased with 0.1 mg·L-1 TDZ treatment compared to the control. Phytotoxic symptoms occurred on plants receiving higher TDZ rates.
Terri W. Starman, Shannon E. Beach and Kristen L. Eixmann
’, ‘Sundaze Bronze’, and ‘Sundaze Golden Yellow’ bracteantha or strawflower; ‘Lucky Lemon Cream’ and ‘Lucky Peach Sunrise’ lantana ( Lantana camara ); and ‘Cascadias Pink’ and ‘Suncatcher Pink’ petunia. All were planted in soilless media (Sunshine Mix #1
Jessica Phillips, James M. Garner and Allan M. Armitage
Five taxa of Helichrysum Mill. and Brachycome Cass. were recently evaluated for greenhouse production and amenity use. Preliminary studies on the influence of photoperiod, temperature, and growth regulators were conducted for H. bracteatum Vent., (syn Bracteantha bracteata) `Sunray' and `Matilda Yellow', H. apiculatum D.C, (syn Chrysocephalum apiculatum) `Golden Buttons' and Brachycome iberidifolia Benth. `Jumbo Mauve' and `Mauve Delight'. All taxa of Helichrysum were quantitative LD plants, flowering slightly more rapidly under night-break (2200-0200 HR) and extended day incandescent lighting, compared with 9-h short-day treatment. No influence of photoperiod occurred with cultivars of Brachycome. Constant temperature of 12, 20, or 28 °C were provided and all taxa demonstrated a linear decrease in flowering time as temperatures increased. The growth index (average of height and two measurements of width) was also influenced by temperature. Paclobutrazol and daminozide were applied at different concentrations and frequencies. Paclobutrazol was more effective than daminozide in both genera, and daminozide was ineffective in Brachycome.
Shannon E. Beach* and Terri W. Starman
Vegetative annuals are increasing in popularity among greenhouse growers and consumers but little is known about their postharvest shelf life. Twenty-two cultivars from ten species of vegetative annuals were grown to marketability with optimum greenhouse culture. Plants were then subjected to one of three shipping durations (0, 1, or 2 days) in simulated shipping i.e., a growth chamber at 26.7 ± 0.3 °C, 0 μmol·m-2·s-1, and 50% relative humidity. The plants were then moved to simulated postharvest environment i.e., growth room at 21.1 ± 1.3 °C and 6 μmol·m-2·s-1 to evaluate shelf life. Flower number and plant quality rating were measured weekly in addition to observations of plant appearances. Some of the postharvest disorders noted on several species and cultivars were stem die back, leaf chlorosis, stem elongation, bud abortion, flower drop, and flower fading. The majority of the cultivars maintained their quality one-week postharvest although flower drop was common. After the first week of shelf life, decline in vegetative and reproductive tissues were noted in most plants. Cultivars from nine species: Argyranthemum frutescens (L.) Sch. Bip, Bracteantha bracteata (Vent.) Anderb. & Haegi, Calibrachoa hybrid Lave Lex, Diascia ×hybrida, Lantana camara L., Nemesia ×hybrida, Petunia ×hybrida, Sutera hybrida, and Sutera cordata showed decreased flower number and/or quality rating due to shipping duration, with increased shipping duration causing accelerated postharvest disorders. The only species unaffected by shipping duration was Angelonia angustifolia Benth.
Neil S. Mattson and W. Roland Leatherwood
impatiens (+10%), lobelia (+13%), and portulaca ( Portulaca grandiflora Hook. ‘Yubi Summer Joy Wine Red’) (+9%), whereas bracteantha [ Bracteantha bracteata (Vent.) Anderb. & Heagi ‘Golden Beauty’] had a reduced height (–9%). Reduced apical stem
Wagner A. Vendrame, Aaron J. Palmateer, Ania Pinares, Kimberly A. Moore and Lawrence E. Datnoff
increased from 0% to 1% and then decreased at the highest Si treatment rate (2%) ( Fig. 1 ). Similar results were observed by Mattson and Leatherwood (2010) in bracteantha ( Bracteantha bracteata ), lobelia ( Lobelia erinus ), and verbena ( Verbena
Alison Bingham Jacobson, Terri W. Starman and Leonardo Lombardini
bedding plants ( Jones, 2002 ). Reduced end-of-production fertilization resulted in higher quality ratings for an additional week for bracteantha ( Bracteantha bracteata ), nemesia ( Nemesia × hybrida ), and sutera ( Sutera hybrida ) and extended flower