Impact of betacyanins on responses to ultraviolet radiation in Amaranthus tricolor L.

[摘要] Relatively little is known about the physiological significance of betalain pigments. To investigate a possible protective role for betalains (betacyanin), from UV-B irradiation, two cultivars of A. tricolor, Red-Leaf (RL) and Green-Leaf (GL) were obtained and VIGS method was used to produce isogenic derivatives of RL. Short-term responses to UV-B in the leaves were compared with and without detectable betalains. Following exposure, the red and green tissues showed similar decrease in photosynthetic capacity and in the increased production of UV-B stress markers including melatonin, flavonoids, phenolics, and PAL1 and RCD1 gene transcripts. Red tissues showed an increase in photosynthetic pigments under UV-B treatment, whereas the photosynthetic pigments and CAB1 and CAB2 gene transcripts decreased. The responses observed were similar for both highbetacyanin (RL) plants, and green plants (VIGS, GL), from which it was concluded that betacyanin does not have a UV-B protective role in amaranth leaves, under the experimental conditions.

[学科分类] 纳米科学和纳米技术

[关键词] Amaranthus tricolor;betalain;betacyanin;stress;Ultraviolet-B;amaranth