Effects of Exogenous Abscisic Acid on Yield, Antioxidant Capacities, and Phytochemical Contents of Greenhouse Grown Lettuces
详细信息 查看全文
- 作者：Zheng Li ; Xin Zhao ; Amandeep K. Sandhu ; Liwei Gu
- 刊名：Journal of Agricultural and Food Chemistry
- 出版年：2010
- 出版时间：May 26, 2010
- 年：2010
- 卷：58
- 期：10
- 页码：6503-6509
- 全文大小：807K
- 年卷期：v.58,no.10(May 26, 2010)
- ISSN：1520-5118
文摘
Antioxidants and phytochemicals in vegetables are known to provide health benefits. Strategies that enhance these properties are expected to increase the nutritional values of vegetables. The objective of this research is to assess the effects of exogenous abscisic acid (ABA) on yield, antioxidant capacities, and phytochemical content of lettuces grown in a greenhouse. Red loose leaf lettuce (cv. Galactic) and green loose leaf lettuce (cv. Simpson Elite) were cultivated using a randomized complete block design. Three concentrations of ABA in water [0 (control), 150, 300 ppm] were sprayed on the 30th and 39th days after sowing, and lettuces were harvested on the 46th day. Exogenous ABA significantly decreased yield of green and red lettuces. Total phenolic and total anthocyanin contents in red lettuce treated with ABA were significantly higher than in controls, whereas no significant differences were observed in green lettuce. ABA significantly induced the accumulation of chlorophyll b and total carotenoids in lettuces. The phenolic compounds identified and quantified in red and green lettuces included caffeoyltartaric acid, 5-O-caffeoylquinic acid, dicaffeoyltartaric acid, 3,5-dicaffeoylquinic acid, and quercetin 3-(6′′-malonyl)-glucoside. Additionally, cyanidin 3-glucoside, cyanidin 3-(3′′-malonoyl)-glucoside, and cyanidin 3-(6′′-malonoyl)-glucoside in red lettuces were quantified. No significant effects of ABA on these individual phytochemicals were observed in green lettuces, whereas ABA significantly elevated the content of individual phytochemicals in red lettuces except for 5-O-caffeoylquinic acid. Differences among red lettuces with or without exogenous ABA were visualized on the score plots of principal component analyses. Loading plot indicated that multiple phenolic compounds contributed to the observed differences in red lettuces.