Department of Botany, Oklahoma State University, 74078, Stillwater, OK, USA.
Planta. 1992 Jul;187(4):517-22. doi: 10.1007/BF00199971.
The effect of temperature and relative humidity (RH) on the time course of the rhythmic endogenous changes of chilling resistance was studied in cotton (Gossypium hirsutum L. cv. Deltapine 50) seedlings grown under light-dark cycles of 12:12 h. The resistant phase to 5° C, 85% RH lasted during most of the dark period while to 5° C, 100% RH it was longer and extended into the last half of the light period because a transient phase advance occurred when chilling started at the middle of the light period. Seedlings acclimated by low temperature were resistant throughout the light-dark cycle. A treatment with 100% RH before chilling to acclimated seedlings introduced a sensitive phase that corresponded to that of non-acclimated seedlings. In non-acclimated seedlings, this treatment decreased the resistance but the basic pattern of the rhythm was sustained. Changes in chilling resistance were analyzed under fluctuating temperatures and RHs, and explained taking into consideration the functioning of the circadian clock and environmental induction of resistance.
在光照-黑暗周期为 12:12 小时的条件下，研究了温度和相对湿度（RH）对棉花（Gossypium hirsutum L. cv. Deltapine 50）幼苗抗寒能力节律内源性变化时间进程的影响。在 5°C、85%RH 的抗性阶段持续时间较长，在黑暗期的大部分时间内，而在 5°C、100%RH 的抗性阶段则更长，并延伸到光照期的后半段，因为在光照期中期开始冷却时会出现短暂的相位提前。经过低温驯化的幼苗在整个光照-黑暗周期内都具有抗性。在冷却前用 100%RH 处理驯化的幼苗会引入一个敏感阶段，该阶段与未驯化的幼苗相对应。在未驯化的幼苗中，该处理降低了抗性，但基本节律模式得以维持。在波动的温度和 RH 下分析了抗寒能力的变化，并考虑到昼夜节律钟的功能和环境诱导抗性的作用对其进行了解释。
