Jack Harlan’s
Botanical Legacy By Lauren Quinn “From the Black Sea coast, Trabzon is not particularly impressive. A small point ending in low cliffs is sprinkled with square box-like houses. A few ramshackle warehouses on the waterfront, a single short wooden dock, a large new government-built warehouse for filberts, some ruins of medieval fortifications about the town were all I could see from the deck of a little Turkish coastal steamer. My interpreter and I stood by the rail and watched the ship maneuver to within a couple hundred yards of the dock. This was an exciting moment for me and the beginning of a long search which is the subject of this story.”† For the late Jack Harlan, the search was long indeed. The world-renowned crop geneticist and former Illinois crop sciences faculty member spent his career scouring the globe for undiscovered crop cultivars and their wild and weedy relatives. He believed his explorations might uncover genes that could revolutionize modern cropping systems. And he was right. During travels in Turkey in 1948, Harlan collected a wheat plant he called “miserable looking.” It was put aside for 15 years, until a disease called stripe rust hit epidemic proportions across the wheat-growing country of the northwestern U.S. It turns out the Turkish wheat was robust in its resistance to four types of stripe rust, as well as multiple other diseases. The majority of today’s wheat cultivars contain genes from that sad little wheat plant, preventing millions of dollars in crop losses every year. Chance Riggins, research assistant professor in the Department of Crop Sciences, says there are countless stories like that, with many yet to be told. Riggins curates Harlan’s collection of herbarium specimens— dried, pressed plants and seeds—which he describes as a gold mine of genetic resources. Riggins just needs to organize the mine. When Harlan retired from the University of Illinois in the 1980s, his massive collection of specimens was boxed up and stored in the basement of Turner Hall. It remained in storage, untouched and untapped, for 20 years until Riggins came along. Now he’s slowly sorting through the trove. But with 55,000 specimens, he’s barely made a dent. “The specimens are all there, but they haven’t been properly labeled. There are 40- to 50-year-old notebooks, all handwritten, stuff you’re not going to find anywhere else,” Riggins says. “Harlan and his colleagues collected from places that are very difficult to get to now, including centers of origin for world ag—the Middle East, Afghanistan, Pakistan, Iran, Africa. It’s truly amazing what’s there. If you’re interested in history, archaeology, anthropology, or crop science, the collection is really cool, but it’s a nightmare if you’re trying to curate it.” Riggins says that even 50-year-old dried specimens can be used to improve crops today. With modern tools, scientists can extract DNA from a single seed or a tiny fragment of dried leaf. Once the materials in the collection are mounted, labeled, and digitized, Riggins hopes, geneticists, taxonomists, and breeders will recognize and use the resource for what it truly represents: the next major breakthrough in plant breeding. †From Harlan’s unpublished 1950 manuscript, Trebi Trail.
“For the sake of future generations, we must collect and study wild and weedy relatives of our cultivated plants as well as the domesticated races. These sources of germplasm have been dangerously neglected in the past, but the future may not be so tolerant. In the plant breeding programs of tomorrow we cannot afford to ignore any source of useable genes.” —Jack Harlan Fall 2018 | ACES@Illinois | 27
