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Craig J. Frey, Xin Zhao, Jeffrey K. Brecht, Dustin M. Huff, and Zachary E. Black

, systematic research of high tunnel production is scarce in subtropical growing systems, where conducive environments lead to persistent disease and pest problems. Grafting as a management tool has been increasingly used in tomato production in the United

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Amy F. Iezzoni

The sour cherry (Prunus cerasus L.) industry in the United States is a monoculture of a 400-year-old cultivar from France named `Montmorency'. To provide a solid germplasm base to breed alternatives to `Montmorency', cherry germplasm was systematically collected over a 15-year period from its ancestral home in Central and Eastern Europe and introduced to the U.S. The strategy of germplasm collection using pollen, seed and budwood importation of highly quarantined species is discussed. Germplasm resulting from this effort is highlighted as well as an example of commercial success. Finally, the “recycling” of this immense germplasm collection to search for dwarfing precocious rootstocks for sweet cherry is described.

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Mingqi Wang, Lixin Peng, and Banghua Wu

Based on our investigation of hazelnut germplasm and Thompson's evaluation system for European hazelnuts, an in-depth study on character description of hazelnut germplasm was conducted from 1991 to 1994. Eighty characters were evaluated for the 58 tested species. It was found that eight characters should be eliminated from Thompson's system, such as annual branch length and hair, lentical color, and serration depth. The best leaf sampling position, sample volumes for quantitative characters, and scoring standards were also determined. Therefore, an advanced evaluation system for hazelnut germplasm was developed. The advanced system is easier and simpler, and will significantly expedite systematical studies of hazelnut germplasm.

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Robert T. Eddy and Clifford S. Sadof

Horticulture businesses will be encouraged to hire qualified individuals with disabilities due to the enactment of the Americans with Disabilities Act of 1990. Maintaining a safe workplace is a considerable challenge due to the use and storage of restricted-use pesticides. In a vocational training program, two persons with mental disabilities were trained to be effective Integrated Pest Management scouts using systematic teaching procedures. Trainees acquired employable skills while providing a service that enabled management to reduce use of conventional pesticides on a greenhouse poinsettia crop by up to 65%.

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John D. Lea-Cox*

Environmental and human safety regulations are now an inevitable part of horticultural crop production. For most businesses, worker training and the subsequent collection and administration of data required for reporting purposes is often regarded as an economic burden. There are few systematic models that firstly provide an ecompassing approach to this business requirement, but more importantly which provide resources that simplify and perhaps automate the reporting of data to any significant degree. A good environmental management system (EMS) should provide a framework to systematically plan, control, measure and improve an organization's environmental performance and assessment. Significant environmental improvements (and cost savings) can be achieved by assessing and improving management and production processes, but only if the data are collected and analyzed quickly and easily. Many times, growers do not realize the relationship between their improved environmental performance and other key EMS benefits, such as reduced liability, better credit ratings, enhanced employee performance, improved customer relations, marketing advantages together with improved regulatory compliance. The International organization for Standardization (ISO) 14001 series is the most widely accepted international standard for EMS. Growers in most states in the US are required to document their use of pesticides and other agrochemicals that can impact human health, and in some states are also required to to document and monitor their applications of water and nutrients, in an effort to environmental pollution. This paper will illustrate the key elements of environmental management systems and how this can be integrated into production management using process management software.

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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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Zhang Deshun and Jia Xiangyun

Taking Beihua shan and Wuling shan mountain as examples, the author investigated the Wild Ornamental Plants (WOP) resources in mountain area of northern China in detail with ecological systematic sampling method. The meteorological data of no meteorological observed plots was reckoned theoretically using statistics. And then the main factors that influence the WOP distribution were sifted out by the progressive regression analysis. At last the optimized chains of adaptability with which the WOP will be introduced from mountain to urban area and of most suitable place on which certain plants will be introduced were defined. In order to enrich the capital Beijing's afforestation materiels, this paper offers a reliable basis in terms of theory.

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Fachun Guan, Shiping Wang, Rongqin Li, Mu Peng, and Fanjuan Meng

To analyze the evolutionary level of Prunus mira Koehne (Prunus mira Koehne Kov et. Kpst), 15 kinds of pollen grains from five altitudes were observed using a scanning electron microscope (SEM). This study demonstrates that pollen morphous P. mira has high variation; specifically, individuals from higher altitudes are much more evolved than those from lower altitudes. This is the first time the pollen morphology of P. mira has been systematically illustrated. Furthermore, 12 random amplified polymorphic DNA (RAPD) primers generated clear and repeatable bands among all individuals based on RAPD; 107 bands ranging from 200 bp to 2000 bp were generated with an average of 8.92 bands per primer. Thus, the RAPD technique proved to be a powerful tool to reveal variation on P. mira. This study provides comprehensive information for genetic diversity of P. mira from different altitudes.

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Chengyan Yue, Jingjing Wang, Eric Watkins, Stacy A. Bonos, Kristen C. Nelson, James A. Murphy, William A. Meyer, and Brian P. Horgan

The development and evaluation of new turfgrass cultivars require considerable resources. A systematic understanding of the breeders’ and distributors’ trait selection behavior can provide a basis for making adjustments and improvements based on industry needs and thus accelerate the breeding process and make it more efficient. The objective of this study is to investigate the selection priorities for turfgrass traits and identify the most influential factors affecting turfgrass breeders’ and distributors’ likelihood of selecting turfgrass traits. Results show that the most important trait clusters for both breeders and distributors were abiotic stress resistance and growth characteristics. Breeders were more likely than distributors to select appearance traits when setting trait priorities. Program characteristics such as program size, education level, and being a male respondent had positive effects on the reported likelihood of selecting studied turfgrass traits, and these effects varied for different trait clusters.