光照对血橙果实内外着色调控的影响

Effects of light on the regulation of coloration in blood orange peel and pulp

【目的】分析血橙在不同光照条件下果皮、果肉中花色苷和类胡萝卜素含量动态变化,获得光照对血橙内外着色的调控功能信息,为后期改善血橙外观品质提供科学依据。【方法】在塔罗科血橙果实转色前期采用不同透光率的果袋对果实进行梯度遮光处理,测定分析梯度遮光处理下血橙转色过程中果皮和果肉中花色苷及类胡萝卜素含量的动态变化规律,利用LC-MS法对黑袋处理和对照血橙果皮中花色苷类物质进行定性和定量分析。【结果】对照血橙果皮和果肉中的花色苷在花后215d开始缓慢合成,花后245d快速合成。套袋延缓果皮中花色苷的合成时间,降低其含量,但不影响果肉中花色苷的合成;在影响程度上,白袋处理对血橙果皮花色苷合成影响较小,棕袋和黑袋处理后基本不着色。血橙果皮和果肉中的类胡萝卜素合成规律不同,各种处理下的血橙果皮类胡萝卜素含量均在花后135~275d呈U形变化特点,以花后185d为分界点,先降后升,而果肉类胡萝卜素含量一直呈直线上升趋势。套袋影响血橙果皮类胡萝卜素的合成,但并不影响果肉中类胡萝卜素的合成;在影响程度上,白袋处理影响最小,基本与对照相近,棕袋和黑袋处理影响较大,两种果袋均使血橙果皮类胡萝卜素含量下降32%。在塔罗科血橙果皮中检测到矢车菊素-3-葡萄糖苷、矢车菊素-3(6''一丙二酰)葡萄糖苷和飞燕草素-3-芸香糖苷等主要花色苷类型。【结论】光照是调控塔罗科血橙果面着色的重要环境因子,但不参与调控果肉中色素的积累。光照影响血橙外观品质主要是通过调控果皮花色苷和类胡萝卜素的合成积累,且花色苷是最主要因子。血橙提质增效需从建园、技术上着重考虑光照因素,套袋虽对果面洁净有利,但不利于血橙外观色泽品质提升。

【Objective】Dynamic analysis of the changes of anthocyanins and carotenoids in the peel and pulp of blood orange under different light conditions was conducted to obtain information on the regulation of light coloring inside and outside blood orange,and provide a scientific basis for improving the appearance quality of blood orange in the later stage.【Method】Bags with different light transmittances were used to conduct gradient shadings on Tarocco blood orange fruits in the early stage of colour-changed period. The total anthocyanin and carotenoid content dynamics in blood orange peel and flesh during color change period under the gradient shading treatment were determined. Qualitative analysis and quantitative analysis of anthocyanins in black bag treated and control blood orange peels were carried out by LC-MS.【Result 】The anthocyanin in the peel and pulp of the control Tarocco blood orange began to slowly synthesize at 215 d after flowering,and rapid synthesis began 245 d after flowering. The bagging delayed the synthesis time of anthocyanins in the peel and reduced the content,but did not affect the synthesis of anthocyanins in the pulp. In terms of the degree of influence, the white bag treatment had little effect on the anthocyanin synthesis of the blood orange peel,and the oranges in brown bag and the black bag were basically not colored after being treated. The synthesis of carotenoids in blood orange peel and pulp was different. The carotenoid content of blood orange peel under various treatments showed U type synthetic dynamics during 135-275 d after flowering,and with day 185 as the turning point,the carotenoids decreased first then in-creased. And the carotenoids of the flesh have been rising straight. Bagging affected the synthesis of carotenoids in the blood orange peel without affecting the pulp. In terms of the degree of influence,the white bag had the lowest impact and was basically close to the control. Brown bags and black bags had a higher impact,and the both reduced the carotenoid content of the blood orange peel by 32%. Tarocco blood orange contained three major anthocyanin types:cyanidin-3-glucoside, cyanidin-3-(6''-malonyl)-glucoside and delphinidin-3-rutinoside.【Conclusion】Illumination is an important environmental factor regulating the coloration of the fruit of Tarocco blood orange,but it does not participate in regulating the accumulation of pigment in the flesh. The effect of light on the appearance quality of blood orange is mainly through the regulation of the synthesis and accumulation of anthocyanins and carotenoids in fruit,while anthocyanins are the main aspect. To improve the quality of blood oranges,it is necessary to focus on the lighting factors from the construction of orchards and technical improvements. Although bagging is beneficial to the cleansing of fruit,it is not conducive to the improvement of the color quality of blood oranges.