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

temperatures predominate. Despite the increasing information obtained from high tunnel studies in northern temperate regions in the United States, there is scarce systematic research regarding high tunnel application and adaptation in subtropical organic

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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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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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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.

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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.

Open access

Chengyan Yue, Zata Vickers, Jingjing Wang, Neil O. Anderson, Lauren Wisdorf, Jenna Brady, Michele Schermann, Nicholas Phelps, and Paul Venturelli

The present study systematically investigated the effects of warehouse and greenhouse aquaponic growing conditions on consumer acceptability of different basil cultivars. A total of 105 consumers rated their liking of three basil cultivars (Nufar, Genovese, and Eleonora), each grown in three conditions (aquaponically in a greenhouse, aquaponically in a warehouse, both with Cyprinus carpio, Koi fish, and grown in soilless medium). We used linear random effect models to investigate consumer preferences for attributes of basil plants grown in different environments by controlling for individual-specific random effects. Participants generally liked the soilless medium–grown and greenhouse aquaponically grown basil plants more than the warehouse aquaponically grown plants. The soilless medium–grown basil had the highest appearance liking and flavor intensity, followed by the greenhouse aquaponic grown and then by the warehouse aquaponic grown. Aquaponically grown cultivars were rated less bitter than soilless medium–grown cultivars.

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C.J. Simon and N.F. Weeden

The ribosomal genes of the two crab apple (Malus) genotypes White Angel' and `Robusta 5' were characterized to determine the extent of between- and within-genotype heterogeneity. Initial investigations with a cloned sequence of soybean rDNA failed to detect some Malus intergenic spacer region fragments. An alternative probing method that used electrophoretically purified Malus rDNA was developed. Double-digests of total genomic DNA with combinations of 13 restriction endonucleases identified the positions of 35 restriction sites. Restriction site polymorphism was observed both between and within the crab apple genotypes. Ribosomal DNA from White Angel' was cloned in phage and plasmid vectors and mapped with 11 enzymes. The region of the spacer causing length heterogeneity was identified. These clones should be useful as genetic markers and for examining population dynamics and systematic of Malus and closely related taxa.