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A.M. Armitage and Meg Green

The University of Georgia trial garden has been in existence since 1982, and the method of evaluation and distribution of taxa has evolved over the years. Annual and perennial taxa are evaluated systematically, over the entire season, providing season-long summaries for each one. Annuals are evaluated every 2 weeks, and scores are based on plant performance, including foliar health, flower numbers and the appearance of disease and insect damage. Perennials are evaluated similarly, however flowering time, flowering persistence and height in the landscape are also noted. Summaries for each taxon are presented in tabular and graphic form. Many new crops have been evaluated and introduced to the floriculture industry. New crops are placed in the horticulture gardens and evaluated by garden personnel and by commercial growers and landscapers. Plants have been distributed free of charge to propagators and growers, resulting in rapid market acceptance of successful taxa.

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Tehryung Kim and Hazel Y. Wetzstein

It has been shown that perennial woody plants exhibit marked seasonal changes in nutrient content, carbon metabolism, and organ development. A knowledge of seasonal nutrient allocation and temporal accumulation patterns can be useful in the development of fertilization regimes that reflect the biology of a tree crop. Maintenance of optimum leaf nutrient status is an important priority in pecan cultural practice. However, a systematic evaluation of nutrient resorption is lacking in pecan. In this work, seasonal changes in nutrients and carbohydrates were evaluated in pecan trees grown under orchard conditions. In addition, resorption efficiencies of eight pecan cultivars were evaluated. Significant levels of resorption were observed in all essential elements, but cultivar differences were not significant. Seasonal patterns of nutrient and carbohydrate content in leaf, stem, and shoot tissue, will be presented as well as a structural evaluation of abscission zone formation.

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Li-Hong Gao, Mei Qu, Hua-Zhong Ren, Xiao-Lei Sui, Qing-Yun Chen, and Zhen-Xian Zhang

Single-slope, energy-efficient solar greenhouses in China use solar energy as the sole source of light and heat for winter crop production in the region between latitudes 32°N and 43°N. The use of solar greenhouses has greatly reduced energy demand and carbon dioxide (CO2) emissions. Solar greenhouses are the best structure for growing winter horticultural crops in China, and have been adopted by countries such as Japan, Korea, and Russia. Increased proliferation of efficient solar greenhouses in China may contribute to solving worldwide problems such as the energy crisis and global climate change. This article summarizes the structure, function, application, and ecological benefits of energy-efficient, single-slope solar greenhouses in China, based on 20 years of systematic studies. We hope this technology can be applied to regions of similar climate to help reduce energy consumption and CO2 emissions.

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Robert G. Fjellstrom and Dan E. Parfitt

RFLPs were studied in 41 populations of 13 Juglans species to study genetic diversity and phylogenetic relationships. 19 single locus nuclear RFLP loci were used to generate genetic distance/identity matrices based on allele frequencies. 21 probes were used to generate genetic distances and phylograms using shared-fragments with parsimony analysis. Parsimony analysis on fragment data produced a minimal length tree in general agreement with distance data trees, but with additional phylogenetic resolution resembling previous systematic studies. All analyses indicate an ancient origin of J. regia, which has been considered a recently derived species. A 10x difference in heterozygosity was seen among species. Genetic differentiation among conspecific east Asian populations was larger than among east Asian species. The opposite was true for American species. J. hindsii is classified as a distinct species and J. cinerea was included in section Cardiocaryon rather than Trachycaryon, from the diversity analysis.

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Hak-Tae Lim

The phylogenetic relationships between Korean endemic, Hanabusaya asiatica, and its allied groups, including four genera and nine species, were investigated at the DNA level using randomly amplified polymorphic DNA (RAPD) method. Ten primers out of 80 primers (10-mer) screened gave rise to very high polymorphism (99%) in all of the tested plants, producing 153 randomly amplified DNA fragments. H. asiatica was differentiated from its allied groups at the 0.62 of similarity index of RAPDs. This results were in accordance with previous classification based on palynological studies. It was confirmed that H. asiatica could be placed into Korean endemic and suggested that RAPD technique be used as an additional method of phylogenetic relationship for plant systematics.

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John L. Maas, John M. Enns, Stan C. Hokanson, and Richard L. Hellmich

1 Research Plant Pathologist. 2 Horticulturist. 3 Research Geneticist. 4 Research Entomologist. We are grateful to M. Alma Solis, Research Entomologist, Systematic Entomology Laboratory. ARS. USDA, Beltsville, for insect identifications, and

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Thomas E. Marler and Leah E. Willis

We are grateful to C. Hubbuch for systematic guidance in defining the list of species for this survey and to P. Andersen, B. Dehgan, and T. Walters for evaluation and suggestions for improving the manuscript. The cost of publishing this paper was

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Margaret Balbach

Introductory Horticulture at Illinois State University is approved for inclusion in the University Studies Program. This program is comprised of courses whose content is considered of general importance to the educated layperson, rather than to the specialist in the field. Departments may use the University Studies Program as a means of attracting students to the field. This has been done with fair success with Introductory Horticulture. Because the course must provide personal enrichment, be broad in scope, offer a systematic design for further learning, and assure a breadth of knowledge and understanding, this course has been designed to focus on the economies of the various horticultural industries, how they are related to the socioeconomic history of the various regions of the country and how the marketing of horticultural products and enterprises affects the personal life of individuals. Acceptance of this approach has been two-fold: first: student evaluations are positive, a steady enrollment has been maintained, and the course has steadily provided 10% to 15% of new Horticulture students, and second: the University Studies review committee has twice affirmed the “tenure” of Introductory Horticulture in spite of increasingly stringent guidelines that discourage many traditional science courses.

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Timothy J. Smalley and Frank B. Flanders

The Industry Liaison Committee of the American Society for Horticultural Science conducted a survey of the horticulture industry to systematically determine: 1) industry's perception of university training of recent graduates and 2) industry's perception of educational needs for future graduates. A Delphi survey was sent to experts in the fruit, ornamental, greenhouse, turf, and vegetable industry. The respondents expressed dissatisfaction with the level of competence of recent university graduates in personnel management and marketing. The lack of hands-on training in university courses was viewed as a major problem, but the respondents agreed that internships should provide university students with the necessary practical experience and universities should concentrate on the science of horticulture. The respondents indicated that business management and marketing expertise will be more important in the future than knowledge of production techniques; however, they would not be more likely to hire a business major instead of a horticulture major. The following areas of study were ranked for relative importance to be included in the university curriculum (from most important to least): communication skills, horticultural technology, business management, personnel management, plant nutrition and soil fertility, pest control, plant physiology, environmental awareness, plant physiology, plant pathology, accounting, and equipment use and maintenance. A second round of questioning for this Delphi survey is being conducted and results will be presented to verify preliminary results.

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S.S. Miller, R.W. McNew, B.H. Barritt, L. Berkett, S.K. Brown, J.A. Cline, J.M. Clements, W.P. Cowgill, R.M. Crassweller, M.E. Garcia, D.W. Greene, G.M. Greene, C.R. Hampson, I. Merwin, D.D. Miller, R.E. Moran, C.R. Rom, T.R. Roper, J.R. Schupp, and E. Stover

Cultivar and planting site are two factors that often receive minimal attention, but can have a significant impact on the quality of apple (Malus ×domestica) produced. A regional project, NE-183 The Multidisciplinary Evaluation of New Apple Cultivars, was initiated in 1995 to systematically evaluate 20 newer apple cultivars on Malling.9 (M.9) rootstock across 19 sites in North America. This paper describes the effect of cultivar and site on fruit quality and sensory attributes at a number of the planting sites for the 1998 through 2000 growing seasons. Fruit quality attributes measured included fruit weight, length: diameter ratio, soluble solids concentration (SSC), titratable acidity (TA), flesh firmness, red overcolor, and russet. Fruit sensory characteristics rated included crispness, sweetness, and juiciness, based on a unipolar intensity scale (where 1 = least and 5 = most), and acidity, flavor, attractiveness, and desirability based on a bipolar hedonic scale (where 1 = dislike and 5 = like extremely). All fruit quality and sensory variables measured were affected by cultivar. The two-way interaction of cultivar and planting site was significant for all response variables except SSC, TA, russet, crispness, and sweetness ratings. The SSC: TA ratio was strongly correlated with sweetness and acidity sensory rating, but was weakly correlated with flavor rating. The results demonstrate that no one cultivar is ideally suited for all planting sites and no planting site is ideal for maximizing the quality of all apple cultivars.