Effect of red light on geotropism in pea epicotyls.
نویسنده
چکیده
Dose response curves were determined for phytochrome phototransformation and for a phytochrome-controlled decrease in geotropic curvature in epicotyls of dark-grown Pisum sativum L. cv. Alaska. Ten times as much light was required to produce a spectrophotometrically detectable transformation of phytochrome as was required to produce a significant change in the geotropic response. The red light energy required for a 50% phytochrome transformation caused a 90% change in the physiological response.
منابع مشابه
Changes in Nucleic Acids in Phytochrome-dependent Elongation of the Alaska Pea Epicotyl.
Red light, which produces the physiologically active form of phytochrome (Pfr), inhibited epicotyl elongation in intact dark-grown Alaska pea seedlings. This red light response was detectable 3 hours after the light treatment and became pronounced after 5 hours. The growth inhibition was completely reversed by far red light applied immediately after the red or by pretreatment of the seedlings w...
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عنوان ژورنال:
- Plant physiology
دوره 63 1 شماره
صفحات -
تاریخ انتشار 1979