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Michael A. Arnold, Tim D. Davis, and David W. Reed

Surveys were sent to 53 North American universities offering horticulture curricula to characterize the types of degrees offered, student demographics, participation in distance education, remuneration and assistance available for graduate students, and faculty rank and salary distributions. Twenty-five institutions responded. This represented 10 PhD, 14 MS, and 12 M. Agr. or MS non-thesis professional degree programs in horticulture and 13 PhD, 13 MS, 12 M. Agr. or M. non-thesis degree programs in plant sciences or a closely related area. On average, graduate students were predominantly Caucasian (70.7%), followed by Asian (16.1%), Black (3.2%), Hispanic (2.6%), and Native American (0.2%). Most were supported by research assistantships (56.3%), with the second largest group being self-supported (13.8%). Teaching assistantships were a small source of support (4.6%). Stipends (12-month equivalent) where variable among fellowships ($2000 to $30,000), teaching ($6600 to $25,000), research ($2000 to $25,239), extension ($12,000 to $17,000), or combination assistantships ($900 to $26,000). Most assistantships included a stipend plus in-state and out-of-state tuition waivers: about half included medical insurance. Mean full-time in-state tuition and fees was $6,535, while out-of-state was $13,876. Participation in distance courses was greatest for non-degree students (18.3%), and low for all others (9.2% to 6.4%). The average academic unit had 15.1 professors, 8.9 associate professors, 6.8 assistant professors, 0.3 senior lecturers, and 1.6 lecturers with mean reported average salaries of $85,142; $70,132; $58,918; $55,608; and $37,887, respectively.

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Abba Upadhyaya, Tim D. Davis, Daksha Sankhla, and N. Sankhla

Both kinetin and BA promoted in vitro shoot formation from hypocotyl explants of Lupinus texensis Hook. placed on Murashige and Skoog (MS) medium. With either cytokinin, shoot formation was best at ≈4.5 μm. Adventitious root formation was observed only on tissue culture-derived shoots placed in MS media containing 5.4 to 54 μM NAA. IAA and IBA, at concentrations ranging from 5 to 55 μm, failed to stimulate rooting. Even at the optimal concentration of NAA, only 14% of the shoots produced roots. Thus, although hypocotyl explants readily produced shoots, adventitious root formation on these shoots occurred with relatively low frequency. Chemical names used: 6-benzylaminopnrine (BA); indole-3-acetic acid (IAA); indole-3-butyric acid (IBA); 6-furfurylaminopurine (kinetin); 1-naphthaleneacetic acid (NAA).

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Tim D. Davis, S.W. George, A. Upadhyaya, and J.M. Parsons

Factors affecting the greenhouse propagation of firebush (Hamelia patens) by leafy stem cuttings during winter were studied. Without bottom heat (BH), mid-day rooting medium temperature was 22 ± 3 C. About half of the auxin-treated cuttings without BH rooted. Maintaining the rooting medium at 29-39 C increased rooting for auxin-treated cuttings to 96-100% and increased root length and visual rating scores several-fold. Rooting percentage, root length, and visual ratings were consistently high in perlite and low in peat. Stem-tip cuttings and sub-terminal stem segment cuttings with basal stem diameters of 3-5 mm rooted slightly better than stem segment cuttings with basal diameters of 6-8 mm. Stem-tip cuttings not treated with auxin but with BH had rooting percentages of 81-86%. Treatment of stem-tip cuttings with auxin generally yielded 90% rooting or above. Despite this, plants grown from auxin-treated cuttings were indistinguishable from plants grown from non-treated cuttings 2 months after the rooting period. Of the variables studied, BH had the most dramatic effect on rooting of firebush cuttings during winter months.

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Tim D. Davis, Daksha Sankhla, N. Sankhla, A. Upadhyaya, J.M. Parsons, and S.W. George

Seeds of Aquilegia chrysantha Gray were germinated under a variety of temperature regimes. Germination was nearly 90% under a day/night cycle of 25/20C, but was reduced to ≤ 40% under constant 25C or a 25/10C day/night cycle. With days between 25 and 29C (night = 20C), germination percentage dropped gradually to ≈ 60% with increasing temperature. With days >29C, germination declined dramatically such that no germination occurred at 31C. Neither kinetin (4.6 to 46 μm) nor ethephon (6.9 to 207 μm) was able to reverse the inhibitory effects of 33C days. Our results indicate that germination of A. chrysantha seed is sensitive to temperature and that germination ≈ 75% can be obtained under a 25 to 27C day/20C night regime. Chemical names used: 2-chloroethylphosphonic acid (ethephon); 6-furfurylaminopurine (kinetin).

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Tim D. Davis, Steven W. George, Wayne A. Mackay, and Jerry M. Parsons

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Jerry M. Parsons, Tim D. Davis, Steven W. George, and Wayne A. Mackay

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Michael A. Arnold, R. Daniel Lineberger, Tim D. Davis, David W. Reed, and William J. McKinley

A comprehensive survey of American and Canadian universities that offer masters, doctoral, or both degrees in horticulture resulted in responses from 27 academic units. Units were surveyed regarding types of degrees offered, admissions policies, demographic characteristics of students, financial assistance provided to students, faculty ranks and salaries, and metrics by which the programs were evaluated by university administration. About 80% of the programs resided in 1862 Morrill Act land-grant institutions (LG) with the remainder housed in other non-land-grant institutions (NLG). Thirty-eight percent of reporting LG programs existed as stand-alone horticulture departments, whereas horticulture programs were combined with other disciplines in the remainder. Admissions criteria were most consistent among LG programs. Participation in distance education programs was low, but growing. Financial support of graduate students was more common in LG programs. Most schools offered some sort of tuition reduction to those students on assistantships/fellowships and offered health insurance options. Payment of fees was rare and the level of stipends provided varied substantially among programs. International student enrollment was greatest at LG programs and had remained steady in recent years. Gender equity was present among graduate students, with nearly equal male and female enrollment. Most graduate students at both LG (63.6%) and NLG (75.0%) programs were non-Hispanic White; although overall minority enrollment had increased but was still not similar in distribution to that of the general U.S. population. Professors (46.7%) and Associate Professors (28.3%) dominated the faculty ranks while Assistant Professors (19.3%) and lecturers/instructors (5.7%) constituted a much smaller portion of the faculty. Faculty salaries varied tremendously among institutions, especially for senior faculty. Female and ethnic minorities were underrepresented in faculty ranks compared with the general U.S. population. Aside from total graduate program enrollment, the relative importance of various evaluation metrics for programs was highly variable among institutions. Data discussed herein should be useful to universities with horticulture graduate programs for peer institution comparisons during program assessments, accreditation reviews, or for strategic planning purposes.

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Wayne A. Mackay, Steve George, Tim Davis, Mike Arnold, Dan Lineberger, Jerry Parsons, and Larry Stein

The Coordinated Educational Marketing Assistance Program (CEMAP) is one of the oldest marketing assistance programs for ornamentals in the United States. The goal of this program is to identify outstanding plants for Texas and to provide support for the nursery industry, thereby making plants with superior performance available to the people of Texas. The CEMAP program is a cooperative effort between the Texas nursery industry and Texas A&M Univ. The CEMAP Executive Board has eight individuals representing extension, research, and teaching plus two administrative liasions and the Industry Advisory Board has ≈50 members from all segments of the ornamentals industry in Texas. Funding for the CEMAP program comes from direct industry support and from the public through the sale of plant tags or other promotional materials which bear the Texas Superstars logo. The logo is trademarked and licensed to printing companies who handle the administration of royalties to the program. The Executive Board makes the final decision about which plants are designated Texas Superstars. Promotional support for the plants is provided by CEMAP through point of purchase materials and publicity through print, radio, and television. In addition, the Texas Nursery and Landscape Association in cooperation with the Texas Department of Agriculture are conducting a publicity campaign to inform the public about Texas Superstars.

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Wayne A. Mackay, Steve George, Jerry M. Parsons, Greg Grant, Tim D. Davis, and Larry Stein

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Michael A. Arnold, R. Daniel Lineberger, Tim D. Davis, Steven W. George, Wayne A. Mackay, Greg D. Grant, Jerry M. Parsons, and Larry A. Stein

Plant trialing and marketing assistance programs have become popular in recent years with several state and some regional programs emerging. Successful implementation requires considerable labor, facilities, and monetary resources for evaluation of large numbers of taxa over several years to ensure that plants are well adapted to the region of interest. Research and development funds, dedicated facilities, and cooperator commitment to trialing programs can be limiting during the early years of the programs. Involvement in plant trialing programs allows students to be exposed to plot layout planning, statistical design, plant maintenance, data collection and analysis, and professional communication of trial results. Construction of facilities for conducting plant trials, growing plants for use in trials, trial installation, and maintenance of plants all provide practical hands-on horticultural training. Replicated plant trials provide the latest information on regionally adapted taxa for inclusion in classroom instruction and publications. Plant trialing programs benefit from labor assistance, development of dedicated facilities, and the opportunity to share equipment and supplies among teaching, trialing, and student research projects.