Betacyanin accumulation in the leaves of C 3 halophyte Suaeda salsa L. is induced by watering roots with H 2O 2

Abstract

Seeds, 5-day and 10-day-old seedlings of C 3 halophyte Suaeda salsa were watered, sprayed and infiltrated with 0, 0.10%, 0.33% and 1.00% hydrogen peroxide (H 2O 2) solution to examine whether H 2O 2 is involved in the betacyanin accumulation. H 2O 2 treatments led to the most significant betacyanin accumulation in the shoots of Suaeda salsa seedlings when seeds were watered with H 2O 2 solution. The increase of betacyanin content was the highest and that of H 2O 2 content was the lowest in leaves, while the increase of betacyanin content was the lowest and that of H 2O 2 content was the highest in roots of seedlings obtained from seeds watered with H 2O 2 solution. When leaves of 5-day and 10-day-old seedlings were sprayed and infiltrated with H 2O 2 solution, the H 2O 2 content was enhanced significantly, but the increase of betacyanin content was not notable in leaves, and the content of betacyanin and H 2O 2 was also at a lower level in roots. The H 2O 2 content in organs of Suaeda salsa seedlings was not proportional to betacyanin content, and the betacyanin accumulation in leaves was correlated with the H 2O 2 production in roots rather than that in leaves and stems. These results suggested that the oxidative stress signal leading to betacyanin production in H 2O 2 treatments may be perceived by roots initially, then the signal was transferred to leaves; the signal transduction was performed and betacyanin accumulation was induced in leaves of Suaeda salsa.