Redistribution of growth during phototropism and nutation in the pea epicotyl |
| |
Authors: | T. I. Baskin |
| |
Affiliation: | (1) Department of Plant Biology, Carnegie Institution of Washington, 290 Panama St., 94305 Stanford, CA, USA |
| |
Abstract: | First positive phototropism of the third internode of intact, 5-d-old pea (Pisum sativum L.) seedlings, grown under continuous, dim red light, showed maximal response following a photon fluence of 3 mol·m-2 blue light. Greater or lesser fluences (with irradiation time 100 s or less) caused less bending, no response being detectable above 300 or below 0.03 mol·m-2. Bilateral irradiation with blue light caused no detectable inhibition of growth rate over that range of fluences. The linear nutation of the pea third internode was shown to be driven by a balanced oscillation of growth rate such that the overall growth rate was little changed during the oscillation. Phototropic stimulation changed neither the amplitude nor the period of nutation. Nutation and phototropism probably regulate growth independently. Phototropism in response to the optimal blue light fluence was caused by concomitant depressed growth on the irradiated side and stimulated growth on the shaded side of the bending internode. These results are consistent with the Cholodny-Went hypothesis which states that unilateral blue light induces a lateral redistribution of a growth regulator.Abbreviations R red light - BL blue lightCarnegie Institution, Department of Plant Biology paper No. 921 |
| |
Keywords: | Blue light Growth redistribution Nutation Phototropism Pisum (phototropism) |
本文献已被 SpringerLink 等数据库收录! |
|