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Robert C. de Wilde

Abstract

In 1946 Kabachnik and Rossiiskaya (96) reported the chemical synthesis of “2-chloroethanephosphonic” acid and in 1963 Maynard and Swan (125) described the formation of ethylene from this compound. When (2-chloroethyl)phosphonic acid (ethephon; also variously cited as 2-chloroethanephosphonic acid, Amchem 66-329, CEPA and Ethrel® disintegrates, it releases ethylene and also chloride and phosphate ions (43, 67, 125, 196, 202) Ethephon is essentially stable in aqueous solutions below pH 4. When the presence of hydroxyl ions is increased and the pH rises above 4, disintegration of the chemical takes place. The pH of the cytoplasm of plant cells is generally greater than 4, so the plant growth activity of ethephon has been attributed primarily to its ability to release ethylene to plant tissues (14, 43, 132, 195, 196). Ethrel formulations provide a convenient way to apply ethylene without the need of gas-confining chambers.

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Edward P. Glenn, Jaqueline Garcia, Rene Tanner, Chelsea Congdon, and Dan Luecke

Free access

David Hannaway

To demonstrate current electronic communication capabilities, an on-line demonstration of the Forage Information System (http://www.forages.css.orst.edu) is planned. This will include accessing various forage and grassland web sites and exploring available information resources, thereby demonstrating existing global connectivity and cooperatively developed projects. What does the future hold for electronic communications? We've seen some of the tremendous progress that has been made over the course of the last 100 years. Even the changes of the last decade have been astounding. Since 1969 (the year of the manned moon landing), the number of networked servers has grown from 4 to 13 million! How can we even pretend to forecast the future of development? It's probably sheer folly.

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Harbans Bhardwaj and Anwar Hamama

Sprouts from various seeds are considered healthy for human consumption. However, no information is available about sprouts made from canola (Brassica napus L.) and white lupin (Lupinus albus L.), two new potential alternate crops in the mid-Atlantic region of the United States. Canola sprouts, on an average, contained (g/100 g, dry weight basis) 38.9 oil, and 61.5, 18.6, 9.2, 7.4, 92.6, 64.8, and 27.8 percent of 18:1, 18:2, 18:3, total unsaturated, total saturated, MUFA, and PUFA fatty acids, respectively, in the oil. Corresponding values for white lupin sprouts were: 6.5, 43.0, 24.9, 9.3, 17.9, 82.1, 47.9, and 34.2. Canola sprouts contained 26.9% protein, whereas white lupin sprouts contained 26.3% protein. Details of these experiments and further results would be presented.

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S.L. Kitto, L. Griffiths, J. Pesek, E. Mackenzie, and K. Bauer

In 1997, we added distance students to a traditional, classroom-taught biotechnology course. To reach distance students, we used a multimedia approach: lectures via videotapes and problem-based learning exercises (PBL) via the Internet. About a third of the course was taught using PBL. The major challenge of the course was to teach the PBL segments to distance and traditional students working in groups. We explored ways to use multimedia technology that would allow distance students to participate in the PBL segments of the course. To assess the effectiveness of the methods used in this project, we compared the distance students with traditional students using measures of perceived and actual knowledge of biotechnology. The student–student interactive PBL segments were challenging because the traditional students were working in “real time” and the distance students were working in “distance time.” Distance students did as well as in the course as traditional students; however, management of groups composed of distance and traditional students was challenging. PBL could probably be used more effectively and successfully with student groups composed solely of distance students.