Topic
Cucumbertree
About: Cucumbertree is a research topic. Over the lifetime, 3 publications have been published within this topic receiving 53 citations.
Papers
TL;DR: Somatic embryogenesis in sweetbay mag- nolia, fraser magnolia, and yellow cucumbertree is reported, and detail re- generation of plantlets from the somatic embryos is reported.
Abstract: Cultures were initiated from immature seeds of three species of magnolia: sweetbay magnolia (Magnolia virginiana L.), fraser magnolia (M. fraseri Walt.) and yellow cucumbertree (M. acuminata var. cordata (Michx.) Sarg.). Immature seeds were bisected longitudinally and cultured on a solidified conditioning medium containing 2 mg 2,4-D/liter, 0.25 mg BA/liter, 40 g sucrose/liter, and 1 g casein hydrolysate/liter. Cultures were maintained in the dark at 22C and transferred to fresh medium at monthly intervals. Within 2 months of culture, somatic embryos or proembryogenic masses proliferated from one end of the endosperm mass. Somatic embryos and proembryogenic masses of each species were cultured on a hormone-free version of the conditioning medium to complete maturation and then transferred to the same hormone-free medium, minus casein hydrolysate, to initiate germination. Germinants were transferred to a hormone-free plantlet development medium for conversion. Plantlets of all three species survived transfer to soil mix and continued to grow. Chemical names used: (2,4 -dichlorophenoxy) acetic acid (2,4-D), N- (phenylmethyl)-1H-purin-6-amine (BA). The genus Magnolia numbers some 80 species scattered throughout southern and eastern Asia, Mexico to Venezuela, and the eastern United States. Of the nine species native to the United States, many are highly desirable as ornamental because of their beautiful foliage and large, showy flowers and fruits. Gardiner (1989) offers detailed descriptions and photographs of several magnolia species in a recent book. Magnolia virginiana L., sweetbay magnolia, is found over a large geographic range in the coastal plain and piedmont of the eastern United States where it occupies low areas and deep, rich soils. It varies widely in habit from a large multi-stemmed deciduous shrub in northern locations to a medium-sized evergreen tree on good sites in the South. The species bears fragrant, white flowers and crimson fruit. Magnolia fraseri Walt., fraser magnolia, is a small to medium tree native to the rich woods of the southern Appala- chians. It has large leaves, up to 30 cm long, characterized by auriculate lobes at the base and fragrant, milky white to pale yellow flowers. Magnolia acuminata var. cordata (Michx.) Sarg., yellow cucumbertree, ranges in habit from a large, spreading shrub to a medium-sized tree. It is a rare species, restricted mainly to several counties in Georgia, but has also been reported in Alabama, Florida, and the Carolinas. Trees produce canary- yellow or, rarely, orange-colored, tulip-shaped blossoms. Magnolias can be propagated from seeds, by rooted cuttings, chip budding, grafting, or layering (Hartmann and Kester, 1983; Gardiner, 1989). To date, there have been no reports of the tissue culture propagation of magnolias, although M. grandi- flora and M. soulangiana embryos have been germinated in vitro (Le Page-Degivry, 1970). Another member of the Mag- noliaceae, yellow-poplar (Liriodendron tulipifera L.), has been regenerated via somatic embryogenesis (Merkle and Sommer, 1986). Here we report somatic embryogenesis in sweetbay mag- nolia, fraser magnolia, and yellow cucumbertree, and detail re- generation of plantlets from the somatic embryos.
34 citations
1 Jan 1965
TL;DR: In the past, uncontrolled clearcutting on many of the good to excellent hardwood sites in the Appalachians has resulted in forest stands composed of the so-called cove hardwoods, a high proportion of which are intolerant species.
Abstract: In the past, uncontrolled clearcutting on many of the good to excellent hardwood sites in the Appalachians has resulted in forest stands composed of the so-called cove hardwoods, a high proportion of which are intolerant species. Characteristically these stands run heavily to yellow-poplar (Liriodendron tulipifera L.), northern red oak (Quercus rubra L.), black cherry (Prunus serotina Ehrh.), basswood (Tilia americana L. and T. heterophylla Vent.), white ash, (Fraxinus americana L.), and sugar maple (Acer saccharum Marsh.); and the first three species generally make up more than half the stems in the overstory. Other trees commonly found in the mixture are red maple (A. rubrum L.), beech (Fagus grandifolia Ehrh.), sweet birch (Betula lenta L.), white oak (Q. alba L.), chestnut oak (Q. prinus L.), hickory (Carya spp. Nutt.), and cucumbertree (Magnolia acuminata L.).
17 citations
TL;DR: It is concluded that 'Ivory Chalice' and 'Yellow Lantern' are promising choices for growers interested in clonal propagation of yellow-fl owered cultivars of magnolia.
Abstract: Certain cultivars of magnolia are desirable in landscapes for their uncommon yellow fl owers. While cultivars derived from Magnolia acuminata L. (cucumbertree mag- nolia) are diffi cult to propagate by stem cuttings, some with mixed parentage appear easier to propagate in this manner. We propagated six yellow-fl owered cultivars vegetatively by applying 0, 8, 16, or 30 g·kg -1 (0, 8,000, 16,000, or 30,000 ppm) indole-3-butyric acid (IBA) in talc to bases of terminal stem cuttings collected 5, 7, 9, or 11 weeks after budbreak. Mean rooting percentage over all cultivars increased from 12% (in the absence of IBA) to 34% (after application of 30 g·kg -1 IBA). Rooting percentage and basal stem diameter of a cutting did not seem related. For each collection date, more cuttings of 'Ivory Chalice' and 'Yellow Lantern' developed roots than the other cultivars. More roots (mean = 5) de- veloped on cuttings of 'Yellow Lantern' collected 5 weeks after budbreak or when treated with 30 g·kg -1 IBA than the other cultivars. 'Butterfl ies' largely remained unresponsive, whereas rooting of 'Golden Sun,' 'Hot Flash,' and 'Maxine Merrill' collected 5 weeks after budbreak was 31%, 22%, and 28%, respectively. When data were analyzed separately for selected cultivars, 63% rooting was observed among cuttings of 'Ivory Chalice' col- lected 7 weeks after budbreak. Rooting percentage was higher (22%) among cuttings of 'Hot Flash' collected 5 or 7 weeks after budbreak in comparison to later collection dates, but harvest date did not infl uence rooting of 'Yellow Lantern,' which ranged from 44% to 59%. Collection of stem cuttings early in the growing season (5 weeks after budbreak) was benefi cial (31% rooting) for inducing rooting among cuttings of 'Golden Sun.' We conclude that 'Ivory Chalice' and 'Yellow Lantern' are promising choices for growers interested in clonal propagation of yellow-fl owered cultivars of magnolia. To maximize rooting among these cultivars, terminal cuttings should be collected within 5 to 11 weeks after budbreak and treated with 16 or 30 g·kg -1 IBA in talc. Early collection dates (5 to 7 weeks after budbreak) improved rooting among cuttings of other cultivars but these, particularly 'Butterfl ies,' remain variably recalcitrant and merit further study. Species, varieties, and cultivars of mag- nolia are popular fl owering trees that can be propagated by seed (species and varieties only), softwood cuttings, semi-hardwood cuttings, micropropagation, layering, budding, and grafting (Callaway, 1994; Dirr and Heuser, 1987). Plants are valued for their showy fl owers, foliage, or fruits, but all taxa are not equally easy to propagate, nor do they respond similarly to a single method of propagation (Hartmann et al., 2002). Demand for yellow-fl owered selections of magnolia has increased, and a large number of hybrids are derived from Magnolia acumi- nata and M. denudata Desr. (yulan magnolia) (Dirr, 1998). Other taxa used to obtain yel- low-fl owered hybrids and cultivars are M. kobus DC. (kobus magnolia), M. acuminata L. var. subcordata (Spach) Dandy (yellow cucumbertree), and Magnolia ×soulangiana Soul.-Bod. (saucer magnolia) (Knox, 2001). Hybrids derived from M. acuminata tolerate variable soil conditions and exhibit delayed fl owering, which prevents frost damage to flowers (Callaway, 1994). Nevertheless, because stem cuttings of M. acuminata and M. denudata do not root easily, many of their yellow-fl owered hybrids also carry this trait, and rooting generally is less than 40% (Dirr and Heuser, 1987; Knox, 2001; Owen et al., 2001). Consequently, these primarily are propagated by budding, grafting, or tissue culture. For most growers, however, inducing root formation on stem cuttings is the most feasible method of vegetative propagation. Despite clonal propagation, some variation in fl ower color is observed among yellow-fl ow- ered cultivars of magnolia in northern Florida, and color can vary from year to year (Knox, 2001), due perhaps to variation in weather and/or soil conditions (Tessmer, 1998). The yellow color (listed in the order of decreasing color intensity) is consistently more intense among fl owers of 'Butterfl ies,' 'Golden Sun,' 'Maxine Merrill,' and 'Hot Flash' compared to the fl ower color of 'Ivory Chalice' and 'Yellow Lantern,' which are cream or pale yellow (G.W. Knox, personal observation). These cultivars are of interest to growers and consumers, but experimental methods and statistical treatment of results have not been reported for their vegetative regeneration. Physiological developmental stage of the cuttings or time of year when cuttings are harvested infl uences rooting among cuttings of many woody species (Hartmann et al., 2002). While stem cuttings of certain plants produce roots easily at any time of year, species and cultivars of magnolia generally have a narrow 'window of rootability,' which also may vary among cultivars (Dirr and Heuser, 1987). Deciduous taxa of magnolia produce roots when softwood cuttings are used (Ellis, 1988; Hartmann et al., 2002), and although some cultivars have been rooted by using softwood cuttings (Ellis, 1988), experimental methods and results are not available, to our knowledge, to indicate the sensitivity of abovementioned yellow-fl owered cultivars to time of cutting collection. Auxins induce adventitious rooting on stem cuttings of many woody plants, including spe- cies and cultivars of magnolia (Hartmann, et al., 2002). A range from 5 to 20 g·kg -1 IBA in talc often is used to propagate cuttings of magnolia, but variation among taxa is known (Dirr and Heuser, 1987; Ellis, 1988; Hartmann et al., 2002). Although the effect of indole-3-butyric acid (IBA) on cuttings of the abovementioned yellow-fl owered cultivars is unknown, some general, non-statistical reports describe vegeta- tive propagation of a few cultivars and parent taxa. For example, rooting of some yellow- fl owered cultivars, including 'Hot Flash' and 'Ivory Chalice,' ranged from 50% to 100% (Knox, 2001), but the infl uence of IBA, number of cuttings, physiological stage, date of collec- tion, and environmental conditions during the experiment were not reported. Among parent taxa, there are no reports, to our knowledge, to describe root formation on cuttings of M. acuminata, which is one of the parents of all yellow-fl owered cultivars included in this study. However, 85% to 100% of the wounded cuttings of M. denudata collected in early June in the northeastern U.S. developed roots after application of 3 to 8 g·kg -1
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Performance Metrics
| Year | Papers |
|---|---|
| 2006 | 1 |
| 1990 | 1 |
| 1965 | 1 |