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  • Author or Editor: Tim D. Davis x
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Plugs of Zinnia elegans Jacq. `California Giant' and Tagetes erecta L. `Golden Climax' and `Grange Lady' were treated with foliar sprays of uniconazole solutions at 0, 5, 25, or 50 mg·liter-1 (spray volume = 120 ml·m-2). Ten days later individual plants were transplanted to OS-liter pots for evaluation of subsequent growth and flowering. All uniconazole treatments reduced height 10 days after application; the extent of reduction depended on uniconazole spray concentration. With zinnia, only the 50-mg·liter-1 foliar spray caused undesirable stunting for at least 1 month after transplanting. None of the uniconazole treatments affected time to anthesis for zinnia. With both marigold cultivars, all uniconazole treatments reduced growth the 2 weeks following transplanting. The highest concentration reduced marigold shoot growth during this period to 25% to 30% of untreated controls. Between 2 and 4 weeks after transplanting growth of all uniconazole-treated marigolds recovered to levels similar to the control. Time to anthesis was increased by the 50 mg·liter-1 treatment for both marigold cultivars. These results suggest that foliar sprays of uniconazole at 5 to 25 mg·liter-1 can control plug height during production without adversely affecting subsequent growth and flowering. with both zinnia and marigold, a single GA3 foliar spray of 100 mg·liter-1 at transplanting partially reversed the adverse post-production effects of the 50 mg·liter-1 uniconazole foliar spray.

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A group of 53 institutions of higher education in the United States and Canada offering degrees in horticulture, or closely related plant science degrees, was surveyed to determine various characteristics associated with the degree programs offered, demographics of students and faculty, and selected procedures and practices associated with administration of these graduate programs. Total response rate was 94%, yielding 85% usable completed surveys. Very few programs (0-3 per degree type) were offered via distance education and on average only 4.1% to 4.5% of resident instruction program students participated in distance education courses. Domestic students averaged 64% to 75% of enrollment. Students were 69% to 73% white. Asian students were the predominant minority group at 12% to 16% of enrollment, followed by African Americans (3% to 8%) and Hispanics (1% to 4%). Most institutions provided out-of-state tuition waivers (75%), and often in-state-tuition waivers (61%), to those students on assistantships or fellowships. Typical commitments to students were 3 years for a PhD and 2 years for a master's degree program. Research assistantships were the dominant form of assistance at all institutions (38% to 53% of students), while teaching assistantships contributed significant secondary funding (7% to 13%). With the exception of mean maximum fellowships, mean maximum assistantships ($11,499-$13,999) at non-1862 Morrill Act universities (NMAU) averaged near the mean minimums ($13,042-$14,566) for the corresponding assistantship types at 1862 Morrill Act universities (MAU). Requirements for teaching experience ranged from 41% of PhD programs to 18% of non-thesis master's degree programs. Typical departments contained 29 faculty members, of which 44% were full professors, 27% associate professors, 19% assistant professors, 6% junior or senior lecturers, and 3% were in other classifications. Traditional 12-month appointments (65.9% of faculty) were predominant at MAU. With the exception of junior lecturer positions, mean salaries at MAU averaged $9125, $6869, $8325, and $28,505 more for professor, associate professor, assistant professor, and senior lecturer, respectively, than at NMAU. This study provides useful information for departments undergoing external review or revision of graduate programs.

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Big Bend bluebonnet (Lupinus havardii Wats.) is native to a narrow geographic range in southwestern Texas and produces attractive blue inflorescences (racemes) that may be used as cut flowers. Several crops were produced in the greenhouse to determine postharvest-characteristics of the cut inflorescences. Without any postharvest conditioning treatments, the inflorescences held in water had an average vase life of about 7 days. During this period, an average of 13 flowers abscised per inflorescence. When preconditioned for 4 hours in 40 to 160 mg·liter−1 silver thiosulfate (STS), vase life increased to 10 to 12 days and fewer than three flowers abscised per inflorescence. A commercial floral preservative (Oasis) had no effect on flower abscission or vase life of STS-treated inflorescences. Flower abscission and vase life were the same whether STS-treated inflorescences were placed in floral foam moistened with water or in water alone. Storing STS-preconditioned inflorescences in water at 5C for 72 hours did not affect flower abscission or vase life compared to the unstored control. Dry postharvest storage at 5C for 72 hours caused noticeable wilting, but, on dehydration, these inflorescences still had a vase life of about 8 days. Postharvest characteristics of pink-and white-flowered breeding lines were the same as for the blue-flowered line. These results indicate that cut inflorescences of L. havardii have desirable postharvest qualities and can be stored for up to 72 hours without seriously limiting vase life.

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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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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.

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The Coordinated Educational and Marketing Assistance Program identifies outstanding landscape plants for Texas and provides support for the nursery industry, thereby making superior plants available to Texans. CEMAP funding comes directly from industry and from consumers through the sale of plant tags bearing the Texas Superstar logo. Additionally, the Texas Nursery and Landscape Association and Texas Department of Agriculture is conducting a Texas Superstar publicity campaign. An estimated $10 million in new plant sales have been generated during the first 10 years of this program. Because plants are chosen based on their performance under minimal input conditions, Texas SuperStars greatly reduce their impact on the urban environment.

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