Opposing Actions of Light in Seed Germination of Poa pratensis and Amaranthus arenicola.

  title={Opposing Actions of Light in Seed Germination of Poa pratensis and Amaranthus arenicola.},
  author={Sterling Brown Hendricks and Vivian Kearns Toole and H. A. Borthwick},
  journal={Plant physiology},
  volume={43 12},
Action spectra were measured for suppression of germination of Poa pratensis L. and Amaranthus arenicola I. M. Johnston seed under prolonged or continuous irradiation. The action maxima for both types of seeds are near 720 nm. The maxima are unchanged in position or magnitude in the presence of radiation in the region of 600 to 670 nm adequate to maintain phytochrome predominantly in the far-red-absorbing form. A reversible potentiation of germination to change in form of phytochrome was… 

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* Part of this work was done as a National Research Council Fellow at the University of California, Berkeley. 1 Bonner, J. T., Am. J. Bot., 31, 175 (1944). 2 Skupienski, F. X., Recherches Sur Le