Heide O M, King R W, Evans L T
CSIRO Division of Plant Industry, G.P.O. Box 1600, Canberra, ACT 2601 Australia.
Plant Physiol. 1986 Apr;80(4):1020-4. doi: 10.1104/pp.80.4.1020.
Evidence is presented of an endogenous rhythm in flowering response to far-red (FR) irradiation, with a period of about 12 h (hence semidian rhythm), which persists through at least three cycles in constant conditions of continuous light at 27 degrees C and has a marked influence on the flowering response in Pharbitis nil to a subsequent inductive dark period. The phase of the rhythm is not influenced by real time nor by the time from imbibition or from the beginning of the light period. Rather, it is fed forward from the beginning of the FR interruption to the beginning of the inductive dark period. The period of the rhythm is not affected by irradiance but is longer at cooler temperature. When there are two FR interruptions during the preceding light period, it is primarily the later one which determines the phase of the rhythm, although some interactions are evident. There appears to be an abrupt rephasing of the rhythm at the beginning of the inductive dark period. No overt rhythms which could be used as "clock hands" for the semidian rhythm were detected in photosynthesis, stomatal opening, or translocation.
有证据表明，在对远红光（FR）照射的开花反应中存在一种内源性节律，其周期约为12小时（因此是半日节律），在27摄氏度连续光照的恒定条件下至少持续三个周期，并且对牵牛花花芽分化对随后诱导暗期的反应有显著影响。该节律的相位不受实时影响，也不受从吸胀时或光照期开始起算的时间影响。相反，它是从FR中断开始向前传递到诱导暗期开始。该节律的周期不受辐照度影响，但在较低温度下较长。当在前一个光照期有两次FR中断时，主要是较晚的一次决定节律的相位，尽管一些相互作用很明显。在诱导暗期开始时，节律似乎会突然重新定相。在光合作用、气孔开放或物质运输中未检测到可作为半日节律“时钟指针”的明显节律。
