Messenger - Vol. 4, No. 3, Page T-1 1995 On Technology Planting new ideas At the touch of a button, Agricultural Sciences Prof. John Frett's computer screen displays a full-color photograph of a red maple tree in all its glory. Another click of the button calls up a page of text describing the tree's botanical name (acerubrun), leaf structure and other characteristics. With one more click, Frett's computerized database of plants even offers help for those who can't pronounce acerubrun: "a-cer-RU-brun," the computer says, providing the proper pronunciation in a synthesized voice. Along with the red maple tree, Frett's database-known as the University of Delaware Botanical Gardens Hypermedia Map-now describes more than 200 plants. Anyone who uses the Internet can take an electronic 'tour' of the gardens. An associate professor of horticulture, Frett developed the database, with help from research associate Betsy Mackenzie, because he wanted to provide students and the general public with information about plants growing in the UD's Botanical Gardens. He also wanted to give students greater access to the photographic slides of plants he regularly shows during his classes. Horticulture instructors typically maintain vast libraries of slides and other images, Frett explains. Unfortunately, he adds, students often have only one opportunity to view each slide in the classroom. "Our whole society is image-based," Frett says. "For a lot of students, if they can just store an image of a plant in their memory, that's worth 15 minutes of rote memorization. Images stored in a database give students a quick way to review essential information about plants." Frett and Mackenzie are still adding images to the database by converting slides into digital data that can be stored on a compact disc and then fed into a computer. Ultimately, Frett's database may include enough images and facts to describe up to 1,700 plants. Frett also is working with Dewey Caron, professor of entomology and applied ecology, to incorporate information on insects into the database. "It would be great if we could show what insects affect each plant," he says. Another computerized database helps University students learn to diagnose plant diseases by studying images and electron micrographs accompanied by text. Stored on a videodisc, the database-created by Thomas A. Evans, associate professsor of plant pathology, with associates at the University of Massachusetts and Clemson University and funding from the U.S. Department of Agriculture-contains almost 10,000 images of plant diseases and pathogens. Images of powdery mildew, for example, show how this plant disease appears on such common hosts as roses, vegetables and turf grass. Beneath an image of a begonia afflicted with powdery mildew, text points out that "the fungus obtains its nutrients from the plant by sending haustoria into epidermal cells." And, if a student is still confused, a built-in glossary explains that an haustorium is a "specialized absorptive structure of a parasite." Another, more detailed image shows the student how powdery mildew might look through a microscope's lens. Students probably won't learn to diagnose every possible plant disease by studying videodisc images, Evans says. But, they should begin to recognize the basic categories of plant diseases-including those caused by fungi, nematodes, parasites, bacteria, viruses and abiotic (non-biological) agents. Compared to a faculty member's personal collection of slides, Evans adds, the videodisc offers students a broader range of information. High-quality slides for the videodisc were contributed by plant pathologists at universities throughout the country and by the American Phytopathological Society Press. "After our students graduate, they might go to work in Malaysia or California or Florida," Evans says. "We don't want to train them to work only in limited crop disciplines. We want them to work productively in any geographical region of the world." Copies of Evans' videodisc may be borrowed for individual study at workstation computer laboratories maintained by the College of Agricultural Sciences. Prof. Robert B. Carroll makes use of the videodisc for classroom presentations, too. "Plant pathologists have traditionally been forced to fumble through stacks and stacks of slides and try to bring into the classroom whatever live materials were available," says Carroll. "The videodisc makes a greater number of slides available to students many more hours each day. This has been especially helpful in introductory plant pathology and diagnostic plant pathology lectures and labs."