Search Results
A natural product known as taxol has been approved by the FDA for treatment of ovarian and breast cancers. In addition, preliminary clinical studies have shown encouraging results when using taxol to treat melanomas, lung, head, and neck cancers. Ornamental yews have been identified as a potential renewable source of taxol and related taxanes. Commercial nurseries were surveyed during Summer and Fall 1991 as a basis for estimating populations of Taxus cultivars currently growing in the United States. Clippings of selected cultivars were sampled from nursery fields in Ohio and Michigan to estimate expected clippings yields as a function of cultivar and cultivar age. More than 30 million Taxus plants were reported to be grown by the 19 major nurseries that responded to the survey. About 88% of all Taxus plants reported in the survey were grown in the three-state area of Ohio, Michigan, and Pennsylvania. Taxus × media `Densiformis', `Hicksii', and `Brownii' were found to be grown by nearly all nurseries in the survey; more than half grew T. × media `Wardii' and T. cuspidata `Capitata', while other well-known cultivars seem to have been specialties of one or two nurseries. Annual clippings yields on a dry-weight basis (db) ranged from ≈20 g/plant to 140 g/plant. Expected yields were found to be very dependent upon plant age and cultivar. Taxus × media `Hicksii' appeared to be the most ideal ornamental yew that could provide a renewable source of taxol because of immediate availability and potential for mechanical harvesting of upright clippings. An estimated 3000 to 4000 ovarian cancer patients could be treated annually with the taxol currently available for extraction from T. × media `Hicksii' clippings.
The East Texas Bedding Plant Pack and Garden Performance Trials began several years ago at the Texas A&M University Agricultural Research and Extension Center at Overton (Overton Center) with the goal of providing information on greenhouse and field performance of bedding plant varieties to the local bedding plant industry and consumers of these products. The program began with local trials that have now expanded in scope with the Smith County Master Gardeners Association playing an integral role in performing the trials. Entries are received from most of the major ornamental seed companies doing business in the United States giving the regional industry access to the only comprehensive greenhouse performance trials in this part of the country. Performance evaluation data is important to this industry since it has a wholesale value of over $500 million in the northeast Texas region, of which over $100 million is bedding plant production. The field performance trials are now replicated at the Overton Center, the Dallas Arboretum and Botanical Garden (Dallas Arboretum) and the Texas A&M University Agricultural Research and Extension Center at Dallas (Dallas Center), giving over 5 million consumers in the northeast Texas region the opportunity to see how promising new plants from all over the world perform in the local climate. Plants that grow well in this climate have the potential to reduce inputs needed for production and use in the home or commercial landscape. Many of the top performing varieties from the bedding plant trials are also chosen to be part of the Coordinated Education and Marketing Assistance Program (CEMAP), a statewide testing program headquartered at the Dallas Center in which entries vie for designation as Texas Superstar plants. The comprehensive benefit of the East Texas Bedding Plant Pack and Garden Performance Trials is the link between the rural bedding plant producers and the urban consumers which serves as a basis for improving the quality of life for the citizens of Texas.
The Southern Extension and Research Activities/Information Exchange Group-27 (SERA/IEG-27) is sponsored by the Southern Association of Agricultural Experiment Station Directors. Thirteen universities and the U.S. National Arboretum cooperate with official representatives from extension and research programs. The objective of the group is to identify, evaluate, select, and disseminate information on superior, environmentally sustainable, landscape plants for nursery crop production and landscape systems in the southeastern U.S. Plants are distributed to members responding to a request from cooperators for plant evaluation. Those who agree to cooperate are expected to grow the selected liner to landscape size, then transplant it in a landscape setting. The plant is rated for insect, disease, and cold damage, heat stress, growth rate, ornamental flowering and fruiting, fall color, commercial production potential, landscape potential, invasiveness potential, and insect disease transmission potential. Growth rate is evaluated annually by recording plant height and width. Initial bloom date is reported followed by bloom duration in days. Following evaluation, the group collectively and individually disseminates information gained from the plant evaluation system to a wide variety of audiences.
Many nursery crops are susceptible to root and foliage diseases caused by numerous species of Phytophthora. Phytophthora ramorum causes sudden oak death of trees and ramorum leaf blight and shoot dieback on numerous nursery plants, including rhododendron (Rhododendron spp.), viburnum (Viburnum spp.), pieris (Pieris spp.), and camellia (Camellia spp.) in Europe, the United States, and British Columbia, Canada. We sought to evaluate relative susceptibility of a selection of ornamental nursery crops by inoculating detached leaves with several species of Phytophthora known to infect rhododendrons, and to compare the relative virulence on those species to isolates of P. ramorum. The results indicated that many plants were susceptible under these experimental conditions, while others were not. On a given host, symptoms caused by all species of Phytophthora were identical except for differences in pathogen virulence. Plant species were identical except for differences in pathogen virulence. Plant species within genera or cultivars within species varied in susceptibility to isolates of P. ramorum and other species of Phytophthora. Phytophthora ramorum, P. citricola, P. citrophthora, and P. nicotianae were the most virulent pathogens on most of the host plants inoculated. Some plants were susceptible to several species of Phytophthora, while others were susceptible only to P. ramorum. Inoculation of detached leaves of `Nova Zembla' rhododendron, lilac (Syringa vulgaris), or doublefile viburnum (Viburnum plicatum var. tomentosum) under controlled conditions with different species of Phytophthora or isolates of P. ramorum (both mating types) indicated significant relative differences in species or isolate virulence.
A commercially available microbial inoculant (Plant Growth Activator Plus) that contains 50 microorganisms, primarily bacteria, was evaluated in a soilless container substrate to determine its effects on root bacterial populations and growth response of container-grown plants at three fertilizer rates. The tropical ornamental plants included hibiscus (Hibiscus rosa-sinensis `Double Red'), spathiphyllum (Spathiphyllum `Green Velvet') and areca palm (Dypsis lutescens). The bacterial groups enumerated were fluorescent pseudomonads, actinomycetes, heat-tolerant bacteria, and total aerobic bacteria. Analysis of the inoculant before its use determined that fluorescent pseudomonads claimed to be in the inoculant were not viable. The plant variables measured were plant color rating, shoot dry weight and root dry weight. Only hibiscus shoot dry weight and color rating increased in response to the addition of the inoculant to the substrate. Hibiscus roots also had a significant increase in the populations of fluores-cent pseudomonads and heat-tolerant bacteria. From a commercial production point of view, increasing fertilizer rates in the substrate provided a stronger response in hibiscus than did addition of the microbial inoculant. Furthermore, use of the inoculant in this substrate did not compensate for reduced fertilizer inputs.
The international trade in ornamental plants has increased worldwide in the last several years, with a considerable economic value to exporting countries ( Lopian, 1994 ). According to the U.S. Department of Agriculture (USDA), National Agriculture
-00030.1 Mutegi, E. Snow, A. Bonin, C. Heaton, E. Chang, H. Gernes, C. Palik, D. Miriti, M. 2016 Population genetics and seed set in feral ornamental Miscanthus sacchariflorus Invasive Plant Sci. Mgt. 9 214 228 doi: 10.1614/IPSM-D-16-00030.1 10.21273/HORTSCI14256
Robinia L. (locust) species are among the most widely planted tree species in the world because they are ornamentally attractive, drought tolerant, fast growing, fix nitrogen, have very hard durable wood, and are adaptable to many sites and climates. Recent taxonomic analysis indicates there are four species, black locust (R. pseudoacacia L.); bristly locust (R. hispida L.); clammy locust (R. viscosa Vent.); and new mexican locust (R. neomexicana A. Gray). All four species originate in the southern United States and northern Mexico. Many horticultural cultivars are available. Locusts are tolerant of a wide range of soil types so long as there is good drainage, adequate moisture, and it is not very clayey. The environmental tolerance of locust makes it an excellent candidate for horticultural uses and for future breeding and selection to enhance its many desirable traits. It is easy to propagate via seed, root cuttings, soft- or hardwood cuttings, budding/grafting, or tissue culture. Locust has indeterminate growth. Spacing of plants in plantations is critical for the production of multiple products including high value timber. Locust is known for its ability to withstand drought conditions however at the cost of leaf shedding. Black locust contributes high levels of nitrogen to the soil from nitrogen fixing bacterial symbiosis. The major drawback to large-scale production of black locust in its native range is the damage that occurs from the locust borer (Megacyllene robiniae Forster). When planted outside the range of the locust borer it can be grown successfully as landscape specimen trees and as trees large enough for lumber production when varieties with straight trunks are grown. Damage from locust leaf miner (Odontata dorsalis Thunberg) can greatly detract from the trees ornamental qualities. Its most common use is as a site reclamation species. The tree is also used in honey production. The wood is highly decay resistant and is greatly valued for poles and posts. The wood is extremely hard and easy to work making it highly desirable for many construction uses.
Controlling height of bedding plants can be one of the most difficult challenges for commercial greenhouse growers. Plant growth regulators (PGRs) often are used to inhibit stem elongation and to limit final plant height. Several techniques are
This study was conducted to determine if there is a difference between the career advancement of alumni of ornamental horticulture associate (terminal) degree and nondegree programs. A survey of the alumni of three associate degree and three nondegree training programs was administered, using guidelines from career advancement validation research conducted at Alverno College, Milwaukee. Wis. (Ben-Ur and Rogers, 1994). Six programs were selected from North Carolina, Maine, Ohio, and southeastern Canada, including parts of Ontario and Quebec and all of New Brunswick and Nova Scotia. The programs were selected because of their perceived high reputations, as based on a survey sent to eight selected Longwood Gardens staff (Kennett Square, Pa.) and six professors in the Plant and Soils Science Department at the University of Delaware (Newark). Survey respondents were initially chosen based on their knowledge of the field of horticulture and of ornamental horticulture educational programs. The statistical analysis of the data did not support the presupposition that there would be a significant difference between the career advancement in favor of graduates from horticultural associate degree programs.