L-谷氨酸促进富士苹果花青素积累的效应

Promotion of L-Glutamic acid on anthocyanin accumulation of Fuji apples

为了探索更为经济适用的果实增色技术,以13年生富士苹果为材料,在果实着色初期(9月中旬)用200～800mg/L谷氨酸(Glu)溶液处理,然后分批取样,分析结果表明,不同浓度谷氨酸处理均能明显促进果皮花青素积累,增加果实着色面积,并明显增加果实可溶性糖含量。分析果实中内源5-氨基乙酰丙酸(ALA)含量,发现Glu能够促进内源ALA含量提高,推测Glu促进苹果着色可能与其促进ALA生物合成有关。分析果实着色过程中超氧化物歧化酶(SOD)、过氧化物酶(POD)和抗坏血酸过氧化物酶(APX)等抗氧化酶活性,没有观察到这些抗氧化酶活性与果实着色之间存在着明显的相关关系。

It was reported that 5-aminolevulinic acid （ALA） could promote anthocyanin formation of Fuji apple fruit skin. However, ALA is too expensive to he used for apple production. In order to explore new cheaper methods for increasing apple fruit coloration, experiments were conducted with 13-year-old trees of Fuji apple cuhivar treated with the precursor of ALA biosynthesis, L-glutamic acid （Glu） at the early stage of fruit skin color development. The results showed that 200~800 mg/L Glu significantly promoted anthocyanin accumulation of the skin and increased the soluble sugar content, whereas the chlorophyll content was reduced quickly. Glu treatment also increased levels of endogenous ALA, which is a metabolite of Glu in plants. The results obtained here did not prove any interrelation between anthocyanin accumulation and the activities of enzymes, including SOD, POD, CAT, APX, PPO and PAL.