Mulberry(Morus alba L.)seedlings were used to test hydrogen peroxide(H_(2)O_(2))as a potential systemic messenger in photosynthetic induction.The upper leaf of mulberry was dark-adapted for 45 min and then illuminated...Mulberry(Morus alba L.)seedlings were used to test hydrogen peroxide(H_(2)O_(2))as a potential systemic messenger in photosynthetic induction.The upper leaf of mulberry was dark-adapted for 45 min and then illuminated with photosynthetically active radiation(PAR)of1000μmol m^(-2)s^(-1).Photosynthetic induction and H_(2)O_(2) content in the lower leaf was measured.The results show that pre-illumination of the upper leaf promoted photosynthetic induction and increased endogenous H_(2)O_(2) in the lower leaf.Without pre-illuminating upper leaf,exogenous H_(2)O_(2) treatment on the lower leaf promoted photosynthetic induction.The application of diphenyleneiodonium and trichloroacetic acid on petioles of the upper leaf inhibited H_(2)O_(2) increase in the lower leaf,indicating that H_(2)O_(2) transport was from upper leaves to lower leaves through the phloem.The results show that H_(2)O_(2) might serve as a signal messenger to promote rapid induction of photosynthesis of leaves in lower parts of the canopy and enable plants to use light energy more efficiently.展开更多
基金supported by State Key Laboratory of Tree Genetics and Breeding(Northeast Forestry University)Youth Foundation of Northeast Agricultural University(No.17QC36)。
文摘Mulberry(Morus alba L.)seedlings were used to test hydrogen peroxide(H_(2)O_(2))as a potential systemic messenger in photosynthetic induction.The upper leaf of mulberry was dark-adapted for 45 min and then illuminated with photosynthetically active radiation(PAR)of1000μmol m^(-2)s^(-1).Photosynthetic induction and H_(2)O_(2) content in the lower leaf was measured.The results show that pre-illumination of the upper leaf promoted photosynthetic induction and increased endogenous H_(2)O_(2) in the lower leaf.Without pre-illuminating upper leaf,exogenous H_(2)O_(2) treatment on the lower leaf promoted photosynthetic induction.The application of diphenyleneiodonium and trichloroacetic acid on petioles of the upper leaf inhibited H_(2)O_(2) increase in the lower leaf,indicating that H_(2)O_(2) transport was from upper leaves to lower leaves through the phloem.The results show that H_(2)O_(2) might serve as a signal messenger to promote rapid induction of photosynthesis of leaves in lower parts of the canopy and enable plants to use light energy more efficiently.
