Effects of Three Allelopathic Phenolics on Chlorophyll Accumulation of Rice (Oryza Sativa) Seedlings: II. Stimulation of Consumption-Orientation

三種植物相剋酚酸對水稻葉綠素累積之影響：（二）消耗面的促進

楊棋明(Chi-Ming Yang) ； 張英風(Ing-Feng Chang) ； 林素靜(Shu-Jin Lin) ； 周昌弘(Chang-Hung Chou)

《Botanical Bulletin of Academia Sinica》 45卷2期 (2004/04) Pp. 119-125

https://doi.org/10.7016/BBAS.200404.0119

摘要

The effects of three allelopathic phenolics, o-hydroxyphenyl acetic, ferulic and p-coumaric acids, on the chlorophyllase activity of rice leaf (Oryza sativa cv. TN67) were investigated. Ten-day-old green seedlings of rice were cultured in greenhouse for 16 d in Kimura's culture solution, which was changed every 4 days, with or without 50, 100 or 200 ppm of the phenolic compounds. Just before changing the culture solution, leaves were harvested to determine their chlorophyll (Chl) and chlorophyllide (Chlide) contents, and their chlorophyllase a and b activities. While the Chl and Chlide contents decreased and increased, respectively, causing the molar ratio of Chlide/Chl to increase, as the phenolic concentrations increased; the chlorophyllase a and b activities drastically increased. This suggests that the consumption-orientation of Chl was significantly stimulated by the exogenously applied phenolics. The order of inhibition of growth of the rice seedlings is: ferulic acid＞p-coumaric acid＞o-hydroxyphenylacetic acid. The order of inhibition effect on Chl accumulation is: p-coumaric acid＞o-hydroxyphenylacetic＞ferulic acid. The order of stimulation effect on chlorophyllase a activity is: o-hydroxyphenylacetic acid＞ferulic acid＞p-coumaric acid. The order of promotion effect on chlorophyllase b is: ferulic acid＞o-hydroxyphenylacetic acid＞p-coumaric acid. The different responses of chlorophyllase a and b activities to the same concentrations of allelochemical phenolics suggest that they may be two different enzymes. It is apparent that the three phenolics may enhance the activities of enzymes, such as chlorophyllase and Mg-dechelatase, responsible for the Chl degradative pathway. A combination of the present and the preceding data strongly suggest that the three allelopathic phenolics may comprehensively affect the biosynthetic and degradative pathways of Chl.

關鍵字

植物相剋酚酸 ； 葉綠素 ； 水稻 ； 消耗面

並列摘要

The effects of three allelopathic phenolics, o-hydroxyphenyl acetic, ferulic and p-coumaric acids, on the chlorophyllase activity of rice leaf (Oryza sativa cv. TN67) were investigated. Ten-day-old green seedlings of rice were cultured in greenhouse for 16 d in Kimura's culture solution, which was changed every 4 days, with or without 50, 100 or 200 ppm of the phenolic compounds. Just before changing the culture solution, leaves were harvested to determine their chlorophyll (Chl) and chlorophyllide (Chlide) contents, and their chlorophyllase a and b activities. While the Chl and Chlide contents decreased and increased, respectively, causing the molar ratio of Chlide/Chl to increase, as the phenolic concentrations increased; the chlorophyllase a and b activities drastically increased. This suggests that the consumption-orientation of Chl was significantly stimulated by the exogenously applied phenolics. The order of inhibition of growth of the rice seedlings is: ferulic acid＞p-coumaric acid＞o-hydroxyphenylacetic acid. The order of inhibition effect on Chl accumulation is: p-coumaric acid＞o-hydroxyphenylacetic＞ferulic acid. The order of stimulation effect on chlorophyllase a activity is: o-hydroxyphenylacetic acid＞ferulic acid＞p-coumaric acid. The order of promotion effect on chlorophyllase b is: ferulic acid＞o-hydroxyphenylacetic acid＞p-coumaric acid. The different responses of chlorophyllase a and b activities to the same concentrations of allelochemical phenolics suggest that they may be two different enzymes. It is apparent that the three phenolics may enhance the activities of enzymes, such as chlorophyllase and Mg-dechelatase, responsible for the Chl degradative pathway. A combination of the present and the preceding data strongly suggest that the three allelopathic phenolics may comprehensively affect the biosynthetic and degradative pathways of Chl.

並列關鍵字

chlorophyllase ； chlorophllide ； p-coumaric acid ； ferulic acid ； o-hydroxyphenylacetic acid