phy·​to·​chrome | \ ˈfī-tə-ˌkrōm How to pronounce phytochrome (audio) \

Definition of phytochrome

: any of a group of proteins bound to light-absorbing pigments in many plants that play a role in initiating floral and developmental processes when activated by red or near-infrared radiation

First Known Use of phytochrome

1960, in the meaning defined above

History and Etymology for phytochrome

phyto- + -chrome

Note: The term phytochrome was introduced by the American botanist Harry A. Borthwick (1898-1974) and the biochemist Sterling B. Hendricks (1902-81) in 1960, apparently first in an article coauthored with S. Nakayama, "Failure of photoreversible control of flowering in Pharbitis nil," Botanical Gazette, vol. 121, no. 4 (June, 1960), p. 242, and more formally in the article "Photoperiodism in plants," Science, vol. 132, issue 3435 (October 28, 1960), pp. 1223-28.

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Cite this Entry

“Phytochrome.” Dictionary, Merriam-Webster, Accessed 24 Oct. 2021.

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