Harry Borthwick

Harry Alfred Borthwick (born January 7, 1898 in Otsego , Minnesota , † May 21, 1974 in Silver Spring ) was an American botanist . He is known as the discoverer of phytochrome .

Life

Borthwick turned to influenced by his uncle, the phytopathologist Harry B. Humphrey , the study of botany at the University of Minnesota and Stanford University with a bachelor's degree in 1921 and a master's degree in 1924. From 1922 he was assistant to EC Robbins at the University of California, Davis . There he dealt with the seed development of garden lettuce and carrots and later with photoperiodism at the state agricultural research station in Beltsville (Maryland) at SL Emsveller. Together with Marion W. Parker, he used soybeans as short-day plants and discovered, among other things, that short lighting (a few minutes) at night is sufficient to prevent flowering. Together with Sterling Hendricks , he investigated the range of the spectrum to which the sought-after photoreceptor protein, which triggered the photoperiodism behavior, responded, and found it to be sensitive in the red spectral range (corresponding to a blue or green pigment). Studies on long-day plants (barley) led to the result that the same protein acted there, later referred to as phytochrome . Soon afterwards, together with the researcher couple Toole, they discovered that experiments on germination were even better suited for studying phytochromes than those on flowering, and they discovered the inhibiting effect of light in the dark red spectral range.

He was a member of the National Academy of Sciences and, since 1971, the American Academy of Arts and Sciences . He was President of the American Society for Plant Physiology and received its Stephen Hales Award. He also received the US Department of Agriculture's Distinguished Service Award.

literature

• Sterling Hendricks, Obituary in Biographical Memoirs National Academy, PDF (1.15 MB)
• USDA: Tripping the light switch fantastic (phytochrome research)