Search Results

You are looking at 1 - 3 of 3 items for :

  • Author or Editor: T. Phillips x
  • Journal of the American Society for Horticultural Science x
Clear All Modify Search

Abstract

A single rhizome explant of the Venus fly-trap has the potential to produce 14 or more rooted plantlets in 40 to 60 days when cultured on a medium containing half strength Murashige and Skoog salts, organic components, naphthaleneacetic acid (NAA) at 1.9 mg/liter and 6-benzylamino purine (BA) at 0.2 mg/liter. Cultures were grown in 16 hour cycles of Cool White fluorescent light at 23° to 26°C. Explants derived from either lateral buds or adventitious buds from leaf cuttings have equal potential for rapid multiplication. This same medium produced optimum plantlet size and quality. Supplementing the basal medium with 0.3 or 1.0 mg/liter of GA3 decreased the number of explants and increased the size of plantlets prior to acclimatization. Media containing higher and lower salt concentrations and higher and lower IAA, NAA, 2,4-dichlorophenoxyacetic acid (2,4-D), BA, or 6(γ,γ, dimethylallylamino)-purine (2ip), produced fewer plantlets while increasing deleterious effects. The rapid plantlet multiplication procedure described will increase commercial availability of the plants while decreasing collection pressures on wild germplasm pools.

Open Access

Abstract

Excised whole leaves of in vitro cultured Venus fly-trap plants produced up to 15 adventitious bud- (AB) and lateral bud-derived (LB) plantlets in 60 to 90 days, when cultured on a modified Murashige and Skoog salt medium supplemented with naphthaleneacetic acid (NAA) at 1.9 mg/liter and 6(-γ,γ-dimethylallylamino)-purine (2iP) at 0.2 mg/liter and grown under a 16 hr photoperiod at 22°C. Leaves dipped for 10 seconds to 24 hr in various concentrations of 6-benzylamino purine (BA), 2iP, NAA and indolibutyric acid (IBA) improved the production of plantlets over undipped leaves. A 24 hr 2iP dip at 2.1 mg/liter produced the largest average number of adventitious and lateral bud-dervied plantlets. Lateral bud-derived plantlets are proposed to have arisen from nodes within the rhizomes of previously derived plantlets. Morphologically, the resulting chain-like growth habit of lateral bud-derived plantlets is very unusual and provides an increased number of plantlets for subcultures.

Open Access

The genus Chionanthus, known as fringetrees, is a member of the olive family (Oleaceae). Chionanthus virginicus is an understory tree or shrub with a wide range in forests of the eastern United States and is used as an ornamental tree that is known to be free of insects and disease in the wild. The species is tolerant of a wide range of environmental conditions, and there is interest in developing new cultivars with improved horticultural traits, such as tree form or upright growth habit and superior flowering display that are widely adapted. To identify genepools in the native range of C. virginicus for use in breeding programs, the genetic diversity and population structure were assessed for 274 individuals from 12 locations in four states (Florida, Maryland, North Carolina, and Texas) using 26 simple sequence repeats (SSRs). An average of 12.54 alleles/locus were detected, allelic richness averaged 2.80. Genetic differentiation was 0.11, indicating moderate differentiation among subpopulations. Despite the high genetic diversity and low population differentiation, Bayesian clustering analysis identified six genetic groups that match the geographic distribution of collection sites. Analysis of molecular variance indicated that most (82%) of the variation is explained within individuals, and 11% and 7% of the variation is due to differences among individuals within populations and among populations. Analysis of isolation by distance across all samples showed a weak positive relationship between geographic distance and genetic distance. The C. virginicus samples analyzed in this study indicate there is sufficient diversity for germplasm collection for use in breeding programs. Given the relatively moderate genetic differentiation, there are not likely to be unique islands of genetic diversity that may be missed when gathering parental materials for a breeding program

Open Access