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Edward F. Gilman

Due to the high cost of color separations, few plant materials texts have photographs and line drawings showing each plant at different times of the year and at different ages. CD-ROM computer technology allows the user ready access to this information at a reasonable cost. Horticulturists at the University of Florida have developed three CD-ROM discs for use throughout the U.S. The discs contain more than 3000 pages of text, extensive morphological characteristics and plant use suggestions, in addition to more than 2000 line drawings and nearly 3600 photographs of more than 1,800 plant species. Software developed for DOS and Windows allows the student to generate customized plant lists for landscape sites. Lists can be created to match specific site characteristics, desirable ornamental attributes, or both. Students can also use the programs to help identify unknown plant specimens. Other features allow viewing of insect and disease problems and access to up-to-date control recommendations.

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Steven E. Newman

Hypertext applications have grown from highlighted index referencing tools used in “help” windows to sophisticated file sharing between many computers linked via the World Wide Web (WWW). Software such as Mosaic makes this link easy and convenient by using “Hypertext Markup Language” (HTML). Most universities and many companies have installed WWW servers and have provided disk space for general use. Horticulture departments and many botanical gardens across the country and all over the world are adapting to this technology by providing access to extension information sheets, newsletters, and selected manuscripts. Pesticide chemical manufacturers are also establishing WWW servers with the intent on providing rapid access to pesticide labels and material safety data sheets (MSDS). For local classroom use, HTML using a WWW server can provide an innovative and alternative means for delivering lecture material.

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Bruce W. Wood, Morris W. Smith, Ray E. Worley, Peter C. Anderson, Tommy T. Thompson, and L.J. Grauke

Staminate and pistillate flower maturity of 80 cultivars of young (<15 years old) pecan [Carya illinoinensis (Wangenh.) K. Koch] trees are presented. These patterns show that pollination and receptivity windows within the flowering season can be divided into very early, early, mid, late, and very late season protandrous (Type I) and protogynous (Type II) types. This system therefore provides a seasonally based 30-class Type I and Type II alternative to the standard two-class Type I and Type II system, thus offering enhanced resolution of flowering intervals and an improved means of selecting cultivars to ensure cross-pollination of yard and orchard trees. Scott-Knott cluster analysis of budbreak, nut ripening date, and date of autumn leaf drop segregated cultivars into one of several categories.

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Jeffrey W. Burcaw, Bruce W. Wood, and Michael W. Pool

The authors have developed a mathematical model designed for shade-intolerant tree crops which describes the amount of intertree shading in an orchard. These data are used to formulate an optimal orchard design based on shading reduction in orchards for any tree crop during any developmental window at any global location for either continuous canopy hedgerows or non-intersecting canopies for several different orchard geometries. Variables include tree shape, orchard geometry intertree spacing, row orientation, time and day of year, and geographical coordinates. Optimal orchard designs are based upon the total amount of unshaded canopy surface per unit area which each orchard configuration confers. Results indicate extensive variability of intertree shading between hedgerow and non-intersecting canopies to be largely a function of latitude, regardless of other variables.

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Eric A. Curry and John J. Burke

Development of valid temperature-based models of physiological processes such as seed germination, bud development, vegetative growth, fruit development, or fruit maturation, requires a parameter to link temperature with plant metabolism. The Thermal Kinetic Window (TKW) concept uses the temperature characteristics of an enzyme kinetic parameter, the Michaelis constant (Km) as indicators of metabolic efficiency. Recently, Burke3 has shown that the temperature dependence of the rate and magnitude of the reappearance of photosystem II (PSII) variable fluorescence following illumination corresponded with the optimal temperature described by the TKW for several plant species. The present study investigated the use of the temperature sensitivity of PSII fluorescence in the identification of temperature optima of apple cultivars and rootstocks. 3Burke, J.J. 1990. Plant Physiol. 93:652-656.

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S. B. Sterrett, D. B. Taylor, C. W. Coale Jr., and J. W. Mapp Jr.

An interdisciplinary approach had been developed to examine the production, economic, and marketing feasibility of new crops. The methodology requires the determination of yield potential and product quality, construction of production budgets, and completion of marketing window analyses. Potential for integration of new crops into the existing farm enterprise is assessed using linear programing techniques that consider labor and equipment constraints, crop rotations and best management practices. Risk analyses consider yield, production costs, and price of both new and traditional crops. By using this method, broccoli has been identified as a potential new crop for eastern Virginia, with labor requirements and slush ice availability being the major constraints to integration into vegetable production in this area.

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Shahrokh Khanizadeh and Jamshid Ghavami

UniBase is a Windows-based (95, 98, NT, 2000, or XP) user-friendly software package that was developed for those who are interested in creating their own instant databases, add information to an existing databases or import data and images from Excel in a choice of languages. The software is very useful for germplasm inventory (fruit crops, vegetables, ornamentals, agronomic crops, weeds, chemicals, insects, pests, animals, etc.) and can be used in any breeding program (animal, horticulture, agronomy, etc.) to trace pedigrees and view images and characteristics of progenies. The database can be searched using various criteria and the use of several operators. An unlimited number of images can be stored for each entry and several graphic formats including BMP, JPEG, GIF, TIFF, etc., can be used. Additional information on UniBase and available data and images can be obtained from the authors.

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James Nienhuis

An enigma in the process of domestication of many of our common vegetables is what they looked like and the speed of the process at which they were transformed from the wild progenitors to the modern cultivars. Many vegetables were either domesticated in antiquity or introduced into Europe, often by trade with Africa, the Middle East, or the Americas. Based on genetic information, we often know or can deduce center of origin and the progenitor species of our common vegetables, but we do not have a record of their early history once introduced into Europe. One window to the process of domestication of vegetables is still life art from the Renaissance period. The emphasis of the art form “natura morta” emphasized realism, which allows us to, in some cases, identify species and market classes based on accurate morphological details.

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Duane W. Greene and James R. Schupp

AVG was evaluated for its effect on controlling preharvest drop and influencing ripening of `McIntosh' apples in Maine and Massachusetts. AVG consistently and effectively retarded preharvest drop. AVG was superior to NAA and comparable to daminozide in drop control. Dilute or 2× applications were more effective than applications made at lower water volumes. One application of AVG made 4 weeks before anticipated normal harvest was more effective in controlling preharvest drop than split applications of the same amount made earlier or later. In general, AVG delayed ripening as assessed by a retardation in the development of red color, maintenance of flesh firmness, delayed degradation of starch, and a delayed onset of the ethylene climacteric. We conclude that AVG is an effective drop control compound that is also useful as a management tool to extend the harvest window for blocks of `McIntosh' that would otherwise ripen simultaneously. Chemical names used: aminoethoxyvinylglycine (AVG), naphthaleneacetic acid (NAA), succinic acid-2,2-dimethylhydrazide (daminozide, Alar).

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Basil R. Eastwood

Several factors have emerged recently, have grown in importance, and are now converging rapidly to create a window of opportunity for all of us. These factors constitute six separate but related and important categories: 1) decreasing staff in the U.S. cooperative extension system, 2) increasing complexity of agricultural production technologies, 3) increasing concerns of society, 4) opening of markets globally, 5) increased need for accountability, and 6) rapid progress in computerized information and communication technologies. These factors encourage greater sharing of expertise and resources across states, institutions and departments; more cooperation with the private sector; improved openness and communication on issues of interest to society; greater awareness of our role in the world; and a willingness to consider new approaches. A program approach and model competitively funded program for the future are described.