Rose periwinkle (C. roseus `Little Linda'), a common bedding plant, grown in Hoagland solution #1 with Fe-EDTA at 5 mg/L Fe had normal shoot morphology, but abnormal root morphology. The primary root was twisted and lateral roots were extremely stunted with dichotomous branching. Over a dozen other bedding and foliage plant species had normal root morphology when grown in an identical solution, and cuttings from periwinkle with abnormal roots produced normal roots when rooted in 2 mM CaCl2. When these rooted cuttings were grown in Fe free Hoagland solution #1, root morphology was normal, indicating that the Fe-EDTA caused the problem. Seedlings were then grown in solution for 30 days with Fe supplied as Fe-EDTA (both 5 mg/L and 1 mg/L Fe), Fe-DPTA (5 mg/L and 1 mg/L Fe), Fe-EDDHA (2.75 mg/L and 0.55 mg/L Fe) or Fe2O3 (1 g/L). Solution pH for all were in a normal range of 4.8 - 5.6 Only the seedlings grown with Fe2O3, Fe-EDTA (5 mg/L Fe) and Fe-DTPA (5 mg/L Fe) developed abnormal root structure. All others had normal roots.
Pamela R. Mattis and David R. Hershey
Huan-Keng Lin, Tzu-Yao Wei, Chin-Mu Chen and Der-Ming Yeh
inheritance of double floweredness in Cathranthus roseus HortScience 47 1679 1681 Chen, C.M. Yeh, D.M. 2012 ‘Taoyuan No. 1-Rose Girl’: A double-flowered periwinkle, Catharanthus roseus HortScience 47 1175 1176 Crivellaro, A. McCulloh, K. Jones, F
M. Gabriela Buamscha, James E. Altland, Daniel M. Sullivan and Donald A. Horneck
.0 peat : 0.2 sand (by volume) medium compared with a nonamended control. In contrast, vinca [ Catharanthus roseus (L.) G. Don] shoot length and dry weight were greatest in a peat-based media with sulfated micronutrients (pH not adjusted) or chelated
Wenhao Dai and Victoria Jacques
Periwinkle, a perennial commonly used as a summer bedding plant, is known as the source of vinca alkaloids used to treat lymphocytic leukemia and Hodgkin's disease. It is also one of the natural hosts of many phytoplasma diseases, such as X-disease of major Prunus species, aster yellows, and ash yellows diseases. Therefore, periwinkle is an ideal plant species for phytoplasma disease research, such as disease transmission, species resistance, and resistant gene screening. Periwinkle tissue culture was established by incubating sterile seeds in hormone-free Murashige and Skoog (MS) medium. Plants were successfully regenerated from in vitro leaf tissues of periwinkle. Adventitious shoots were induced when leaf tissues were cultured on Murashige and Skoog (MS) medium or woody plant medium (WPM) supplemented with benzyladenine (BA) and naphthaleneacetic acid (NAA). Nearly 75% of leaf explants produced shoots in both media with 10–20 μm BA and 1 μm NAA. A mean of 4.3 shoots was produced from each explant cultured on WPM, whereas only 2 shoots were produced on MS medium under 16-h photoperiod. Leaf explants under dark treatment for 2 weeks produced big callus only, indicating that light is necessary for shoot formation. Most adventitious shoots were induced from the joint of leaf blade and petiole. In vitro shoots (>1.5 cm) were easily rooted in half-strength MS medium. Addition of NAA dramatically increased root number, with more than 20 roots being induced in 5 μm NAA medium. Rooted plants were transferred to potting medium and grown in a greenhouse.
Glenn B. Fain, Charles H. Gilliam, Jeff L. Sibley and Cheryl R. Boyer
The objective of this study was to evaluate the potential for use of container substrates composed of processed whole pine trees (WholeTree). Three species [loblolly pine (Pinus taeda), slash pine (Pinus elliottii), and longleaf pine (Pinus palustris)] of 8- to 10-year-old pine trees were harvested at ground level and the entire tree was chipped with a tree chipper. Chips from each tree species were processed with a hammer mill to pass through a 0.374-inch screen. On 29 June 2005 1-gal containers were filled with substrates, placed into full sun under overhead irrigation, and planted with a single liner (63.4 cm3) of ‘Little Blanche’ annual vinca (Catharanthus roseus). The test was repeated on 27 Aug. 2005 with ‘Raspberry Red Cooler’ annual vinca. Pine bark substrate had about 50% less air space and 32% greater water holding capacity than the other substrates. At 54 days after potting (DAP), shoot dry weights were 15% greater for plants grown in 100% pine bark substrate compared with plants grown in the three WholeTree substrates. However, there were no differences in plant growth indices for any substrate at 54 DAP. Plant tissue macronutrient content was similar among all substrates. Tissue micronutrient content was similar and within sufficiency ranges with the exception of manganese. Manganese was highest for substrates made from slash pine and loblolly pine. Root growth was similar among all treatments. Results from the second study were similar. Based on these results, WholeTree substrates derived from loblolly pine, slash pine, or longleaf pine have potential as an alternative, sustainable source for producing short-term horticultural crops.
Krishna S. Nemali and Marc W van Iersel
Efficient use of irrigation water is increasingly important in the production of bedding plants. Two approaches to efficient water use include reducing irrigation water wastage during production by growing plants at the optimal substrate water content (θ) and growing species with high water-use efficiency (WUE). However, there is little information on the effects of different θ levels on leaf physiology of bedding plants and variation in WUE among different species of bedding plants. The objectives of this study were to determine the effects of θ on leaf water relations, gas exchange, chlorophyll fluorescence, and WUE of bedding plants and to identify the physiological basis for differences in WUE between two bedding plant species. We grew salvia ‘Bonfire Red’ (Salvia splendens Sellow ex Roemer & J.A. Schultes), vinca ‘Cooler Peppermint’ [Catharanthus roseus (L.) G. Don.], petunia ‘Lavender White’ (Petunia × hybrida Hort ex. Vilm.), and impatiens ‘Cherry’ (Impatiens walleriana Hook F.) at four constant levels of θ (0.09, 0.15, 0.22, and 0.32 m3·m−3) using an automated irrigation controller. Regardless of species, leaf water potential (Ψw) and leaf photosynthesis (A) of all four species were lower at a θ of 0.09 m3·m−3 and were not different among the other θ levels, but stomatal conductance to H2O (g S) was lower at 0.09 than at 0.15 and 0.22 m3·m−3 and highest at 0.32 m3·m−3. WUE of bedding plants at different θ levels depended on species. The WUE of petunia was unaffected by θ, whereas for the other three species, WUE was higher at a θ of 0.09 m3·m−3 than at 0.32 m3·m−3. Differences in WUE between petunia and salvia were partly from differences in photosynthetic capacity between the two species. Based on the response of A to leaf internal CO2 concentration (Ci), mesophyll conductance to CO2 [gm (a measure of photosynthetic capacity)] was higher in petunia than salvia, whereas gas phase conductance to CO2 (gCO2) was similar for these two species, which resulted in higher WUE in petunia than salvia.
Josh B. Henry, Ingram McCall, Brian Jackson and Brian E. Whipker
plant minerals were processed by nitric acid/hydrogen peroxide digestion and determined via ICP-MS. Experiment 2. Two cultivars each of vinca [ Catharanthus roseus (L.) G. Don] and New Guinea impatiens ( Impatiens hawkeri W. Bull) were grown in this
Adam F. Newby, James E. Altland, Daniel K. Struve, Claudio C. Pasian, Peter P. Ling, Pablo S. Jourdan, J. Raymond Kessler and Mark Carpenter
points for Catharanthus roseus L. ‘Cora Lavender’ growing in 13-cm pots from 17 Mar. to 6 May. Substrate had no effect on the irrigation volume applied, leached, or retained, or the number of irrigation events ( Table 2 ). However, irrigation volumes
Thomas H. Yeager, Joseph K. von Merveldt and Claudia A. Larsen
criteria for high-quality reclaimed water deemed suitable for land application. Reclaimed water was obtained as needed from the Kanapaha Wastewater Treatment Facility in Gainesville, FL, for irrigation of ornamental crops that included: vinca [ Catharanthus
Gitta Shurberg, Amy L. Shober, Christine Wiese, Geoffrey Denny, Gary W. Knox, Kimberly A. Moore and Mihai C. Giurcanu
Iersel et al. (1998a , 1998b , 1999 ) reported that growth of impatiens ( Impatiens walleriana ), salvia ( Salvia splendens ), vinca ( Catharanthus roseus ), and petunia ( Petunia × hybrida ) in the nursery generally increased with increasing N