Time-course of Respiration and its Relation to Water : Conditions in Various Plant Species

[摘要] The time-courses of respiratory CO2 evolution of fourteen plant species were examined to elucidate interspecific difference in respiration under the same environmental conditions. The effects of water deficiency and water logging on respiration were also examined in several plant species. The change in respiration rate with time were almost the same in all plant sepecies examined, though the levels of respiration rate were relatively higher in five C4 plants than in three C4 plants and six C3 plants. They decreased after the onset of dark period followed by the temporary increase at midnight and declining again from 8 to 12 hours after the onset of dark period. Both water deficiency and water logging conditions strongly and immediately affected the time course of respiration rate. The temporary rise of the rate at midnight disappeared within one day in both cases. In plants sensitive to flooded conditions the second decrease of respiration rate around 8 to 12 hours after the onset of dark period also disappeared by water logging for 7 days. From these results, it was concluded that the internal processes relating to the change in respiratory CO2 evolution with time were similar among fourteen plant species, and that respiration rate sensitively and quickly reflected the plant growth response to water conditions, which differed among species.

[学科分类] 农业科学（综合）

[关键词] Diurnal change of respiration;経時変化;Interspecific difference;呼吸;Respiration;種間差;Water deficit;水分欠乏;Water logging;湛水