Anthocyanin accumulation and changes in CHS and PR-5 gene expression in Arabidopsis

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植物激素在低磷响应中的作用

植物激素在低磷响应中的作用磷是植物生长发育所必需的大量元素之一。

土壤缺磷是植物生长的限制因素之一。

植物在低磷环境下形成了一系列的生理生化适应机制。

研究发现植物激素在植物应对低磷胁迫中扮演重要的角色。

植物激素的刺激与磷胁迫之间存在着密切的联系。

笔者总结了近几年来植物激素如生长激素、乙烯、赤霉素等与低磷胁迫之间的关系的证据，作为进一步了解土壤中磷有限条件下植物激素的作用的工具。

标签：植物激素；生长激素；赤霉激素；乙烯；细胞分裂素；磷胁迫磷元素是植物生长发育所必需的大量元素之一，在植物的生命活动过程中有重要的生物学功能。

植物在长期进化过程中形成了一系列适应低磷胁迫的机制。

植物感受到低磷信号，就会经过一系列的信号转导过程调控其体内与磷相关的调节基因和结构基因的表达，从而影响植物体内的生理生化过程，并最终表现为一系列可见的特征，包括根系形态结构的变化、生理生化代谢的改变以及与菌类共生等，以最大限度吸收和利用有效磷。

以拟南芥为例，感受到低磷信号后会出现以下表现：（1）拟南芥主根的生长受抑制即主根变短；（2）侧根的数量和长度增加；（3）根毛的长度和密度也会增加；（4）植株矮小，根冠比增加，生物量降低；（5）叶片由暗绿变紫，花青素积累；（6）生长发育受阻，抗性减弱；（7）植物的营养周期变短，提前开花完成生活史等等[1-2]。

植物激素在植物的低磷响应中也起了比较重要的作用，笔者就植物激素在植物响应低磷胁迫过程中所起的作用做了综合分析。

1?生长激素在低磷响应机制中的作用生长激素的极性运输是侧根形成所必需的。

当植物生长在低磷环境中时，施加外源性生长激素能显著地抑制植物主根的生长并促进侧根的形成。

相反的，如果要在高磷环境中造成这样的根系构型则需要比低磷环境中高出10倍甚至100倍浓度的生长激素。

此外，抗生长激素的突变体axr2-1，axr3-1和axr4-1在低磷环境中表现出正常的低磷反应，而iaa28-1则能够抵抗由低磷引起的对根毛和侧根形成的刺激效应。

红肉水果种质现状及研究进展

落叶果树　２０２４，５６（２）：０６－１１·专家论坛· ＤＯＩ：　１０．１３８５５／ｊ．ｃｎｋｉ．ｌｙｇｓ．２０２４．０２．００２红肉水果种质现状及研究进展姚玉新，王菲（山东农业大学园艺科学与工程学院，山东泰安２７１０１８）摘　要：红肉水果富含花青素，具有较高的营养和保健价值，越来越受消费者和育种者青睐。

综述了目前常见的红肉水果资源，包括生产上主要栽培的红肉水果品种；总结了红肉水果中主要的花青素组分，分析了红肉和白肉果实中花青素组分差异；评价了红肉水果资源作为中间材料在育种上的应用，并概述了红肉水果所提取的花青素在保健品、医药、化妆品等行业的应用；结合花青素生物合成途径，概述了果肉着色的调控机制。

最后，讨论了红肉水果存在的主要问题、发展趋势及其主要用途。

关键词：红肉水果；种质资源；育种；营养保健；调控机制中图分类号：　Ｓ６６文献标识码：　Ａ文章编号：　１００２－２９１０（２０２４）０２－０００６－０６收稿日期：２０２４－０１－２９基金项目：山东省果品产业技术体系（ＳＤＡＩＴ－０６－０３）。

作者简介：姚玉新（１９７７－），男，山东泰安人，教授，从事葡萄盐碱抗性、果实次生代谢机制研究工作。

Ｅ－ｍａｉｌ：ｙａｏｙｘ＠ｓｄａｕ．ｅｄｕ．ｃｎＣｕｒｒｅｎｔｓｔａｔｕｓａｎｄｒｅｓｅａｒｃｈｐｒｏｇｒｅｓｓｏｆｒｅｄ－ｆｌｅｓｈｅｄｆｒｕｉｔｇｅｒｍｐｌａｓｍＹＡＯＹｕｘｉｎ，ＷＡＮＧＦｅｉ（ＣｏｌｌｅｇｅｏｆＨｏｒｔｉｃｕｌｔｕｒａｌＳｃｉｅｎｃｅａｎｄＥｎｇｉｎｅｅｒｉｎｇ，ＳｈａｎｄｏｎｇＡｇｒｉｃｕｌｔｕｒａｌＵｎｉｖｅｒｓｉｔｙ，Ｔａｉ’ａｎ，Ｓｈａｎｄｏｎｇ２７１０１８，Ｃｈｉｎａ）Ａｂｓｔｒａｃｔ：Ｒｅｄ－ｆｌｅｓｈｅｄｆｒｕｉｔｓａｒｅａｂｕｎｄａｎｔｉｎａｎｔｈｏｃｙａｎｉｎｓａｎｄｐｏｓｓｅｓｓｈｉｇｈｎｕｔｒｉｔｉｏｎａｌａｎｄｈｅａｌｔｈｂｅｎｅｆｉｔｓ，ｗｈｉｃｈａｒｅｉｎｃｒｅａｓｉｎｇｌｙｆａｖｏｒｅｄｂｙｍｏｒｅａｎｄｍｏｒｅｃｏｎｓｕｍｅｒｓａｎｄｂｒｅｅｄｅｒｓ．Ｉｎｔｈｉｓａｒｔｉｃｌｅ，ｔｈｅｃｏｍｍｏｎｒｅｄ－ｆｌｅｓｈｅｄｇｅｒｍｐｌａｓｍｓｗｅｒｅｒｅｖｉｅｗｅｄ，ｉｎｃｌｕｄｉｎｇｔｈｅｍａｉｎｒｅｄ－ｆｌｅｓｈｅｄｃｕｌｔｉｖａｒｓｉｎｆｒｕｉｔｐｒｏｄｕｃｔｉｏｎ．Ａｎｔｈｏｃｙａｎｉｎｃｏｍｐｏｎｅｎｔｓｗｅｒｅｓｕｍｍａｒｉｚｅｄｉｎｄｉｆｆｅｒｅｎｔｒｅｄ－ｆｌｅｓｈｅｄｆｒｕｉｔｓ，ａｎｄｔｈｅｉｒｄｉｆｆｅｒｅｎｃｅｉｎｒｅｄ－ｆｌｅｓｈｅｄａｎｄｗｈｉｔｅ－ｆｌｅｓｈｅｄｆｒｕｉｔｓｗａｓａｎａｌｙｚｅｄ．Ｔｈｅａｐｐｌｉｃａｔｉｏｎｏｆｒｅｄ－ｆｌｅｓｈｅｄｒｅｓｏｕｒｃｅｓａｓｉｎｔｅｒｍｅｄｉａｔｅｍａｔｅｒｉａｌｓｉｎｂｒｅｅｄｉｎｇｗａｓｅｖａｌｕａｔｅｄ，ａｎｄｔｈｅｉｒｐｏｔｅｎｔｉａｌａｐｐｌｉｃａｔｉｏｎｉｎｈｅａｌｔｈｐｒｏｄｕｃｔｓ，ｍｅｄｉｃａｌｉｎｄｕｓｔｒｙａｎｄｃｏｓｍｅｔｉｃｓｉｎｄｕｓｔｒｙｗａｓｓｕｍｍａｒｉｚｅｄ．Ｂａｓｅｄｏｎｔｈｅｐａｔｈｗａｙｏｆａｎｔｈｏｃｙａｎｉｎｂｉｏｓｙｎｔｈｅｓｉｓ，ｔｈｅｍｅｃｈａｎｉｓｍｕｎｄｅｒｌｙｉｎｇａｎｔｈｏｃｙａｎｉｎａｃｃｕｍｕｌａｔｉｏｎｉｎｆｌｅｓｈｗａｓｒｅｖｉｅｗｅｄ．Ｉｎｔｈｅｅｎｄ，ｔｈｅｍａｉｎｐｒｏｂｌｅｍｓ，ｄｅｖｅｌｏｐｍｅｎｔｔｒｅｎｄｓａｎｄｐｏｔｅｎｔｉａｌａｐｐｌｉｃａｔｉｏｎｓｏｆｒｅｄ－ｆｌｅｓｈｅｄｆｒｕｉｔｓｗｅｒｅｄｉｓｃｕｓｓｅｄ．Ｋｅｙｗｏｒｄｓ：ｒｅｄ－ｆｌｅｓｈｅｄｆｒｕｉｔｓ；ｇｅｒｍｐｌａｓｍｒｅｓｏｕｒｃｅｓ；ｂｒｅｅｄｉｎｇ；ｎｕｔｒｉｔｉｏｎａｎｄｈｅａｌｔｈ；ｒｅｇｕｌａｔｏｒｙｍｅｃｈａｎｉｓｍ第２期姚玉新等：红肉水果种质现状及研究进展红肉水果不同组织均积累花青素，不仅具有较高的观赏价值，而且富含营养物质，越来越受消费者青睐，更多的育种者致力于红肉果树种质培育及创制。

光照对血橙果实内外着色调控的影响

光照对血橙果实内外着色调控的影响作者：杨海健周心智张云贵杨蕾丁志祥来源：《南方农业学报》2019年第09期摘要：【目的】分析血橙在不同光照條件下果皮、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215 d开始缓慢合成，花后245 d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135～275 d呈U形变化特点，以花后185 d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。

关键词：血橙;花色苷;类胡萝卜素;着色;遮光中图分类号： S666.4; ; ; ; ; ; ; ; ; ; ; ; ; ; 文献标志码： A 文章编号：2095-1191（2019）09-2015-07Abstract：【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， thecarotenoids decreased first then increased. 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.Key words： blood orange; anthocyanin; carotenoids; coloring; shading0 引言【研究意义】塔罗科血橙原产于地中海地区，目前在我国四川和重庆广泛栽培。

Does anthocyanin degradation play a significant role in determining pigment concentration in

ReviewDoes anthocyanin degradation play a signiﬁcant role in determining pigment concentration in plants?Michal Oren-Shamir*Department of Ornamental Horticulture,Agriculture Research Organization,P.O.Box6,Bet-Dagan50250,IsraelContents1.Anthocyanins in plants (310)2.Evidence supporting in planta anthocyanin degradation (311)2.1.Degradation during development (311)2.1.1.Loss of red pigmentation in young foliage as it matures (311)2.1.2.Anthocyanin degradation in developing fruit (312)2.1.3.Anthocyanin degradation in developingﬂowers (312)2.2.Degradation due to changes in environmental conditions (312)2.3.Is anthocyanin turnover in plants dependent on environmental conditions? (312)3.Enzymatic degradation of anthocyanins (313)3.1.Anthocyanin degradation in fruit after harvest (313)3.2.Enzymatic degradation of anthocyanins in fruit juices (313)3.3.Active in planta degradation of anthocyanins (314)4.Concluding remarks (314)Acknowledgements (315)References (315)1.Anthocyanins in plantsAnthocyanins are the largest and most diverse group of plant pigments derived from the phenylpropanoid pathway,ranging in color from red to violet and blue[1].They are water-soluble phenolic compounds and part of a large and widespread group of plantﬂavonoids.There are less than20anthocyanidins(aglycones or chromophores of anthocyanins),differing in the number and position of their hydroxyl groups and methyl groups.Anthocya-nidins are modiﬁed by glycosyl and aromatic or aliphatic acyl moieties,resulting in hundreds of anthocyanin molecules that differ in hue and stability.These pigments accumulate in the vacuoles and their stability and hue depend on intravacuolar conditions such as pH,copigmentation with coexisting colorlessPlant Science177(2009)310–316A R T I C L E I N F OArticle history:Received20April2009Received in revised form25June2009 Accepted29June2009Available online7July2009Keywords:Anthocyanin degradationBrunfelsiaPeroxidaseb-GlucosidasePolyphenol oxidase A B S T R A C TIn contrast to the detailed knowledge available on anthocyanin synthesis,very little is known about its stability and catabolism in plants.Here we review evidence supporting in planta turnover and degradation of anthocyanins.Transient anthocyanin accumulation and disappearance during plant development or changes in environmental conditions suggest that anthocyanin degradation is controlled and induced when beneﬁcial to the plant.Several enzymes have been isolated that degrade anthocyanins in postharvest fruit that may be candidates for in vivo degradation.Three enzyme groups that control degradation rates of anthocyanins in fruit extracts and juices are polyphenol oxidases, peroxidases and b-glucosidases.Evidence supporting the involvement of peroxidases and b-glucosidases in in vivo anthocyanin degradation in Brunfelsiaﬂowers is presented.Understanding the in vivo anthocyanin degradation process has potential for enabling increased pigmentation and prevention of color degradation in crops.ß2009Elsevier Ireland Ltd.All rights reserved.*Tel.:+97239683840.E-mail address:vhshamir@.il.Contents lists available at ScienceDirect Plant Sciencej o u r n a l ho m e p a g e:w w w.e l s e vi e r.c om/l o ca t e/pl a n t s c i0168-9452/$–see front matterß2009Elsevier Ireland Ltd.All rights reserved.doi:10.1016/j.plantsci.2009.06.015ﬂavonoids and formation of complexes with metal ions[2,3]. Anthocyanins are located mainly in the epidermal tissue,but are also present in the palisade and spongy mesophyll in leaves and in theﬂesh of fruits and underground storage organs such as sweet potato[4,5].The biosynthesis of anthocyanins has been char-acterized in great detail[6,7].The basic anthocyanin molecule is comprised of two aromatic rings and an oxygen containing heterocyclic ring.One of the aromatic rings is derived from phenylalanine and the second ring from the action of chalcone synthase(CHS),condensing one molecule of p-counaroyl-coA with three molecules of malonyl-coA to produce tetrahydroxy chalcone [8].CHS is theﬁrst committed enzyme in the anthocyanin biosynthetic pathway.The regulation of anthocyanin biosynthesis has also been studied thoroughly and comprises of basic-helix-loop-helix(bHLH)transcription factors,interacting with R2R3 MYB transcription factors to activate either all or part of the anthocyanin genes[9].Many studies generated transgenic plants with either increased concentration or altered composition of anthocyanins inﬂowers,foliage or fruit by manipulating the expression of the anthocyanin regulatory genes[10–15].Conversely,very little is known about the stability and catabolism of anthocyanins in plants.Is there turnover(simulta-neous synthesis and degradation)of the pigments in living plant tissue,or are the pigments stable once they have accumulated in the vacuoles?Can plants actively degrade anthocyanins,thereby controlling pigment concentration via both biosynthesis and degradation?Since the color of fruits,ﬂowers and leaves is of the utmost economic importance in a variety of agricultural products,a better understanding of anthocyanin degradation may reveal ways in which to inhibit the process and consequently increase pigmentation under conditions of low synthesis.Here we review evidence supporting the existence of antho-cyanin turnover and degradation in planta.In addition,we review the knowledge on active anthocyanin degradation processes in in vitro systems such as fruit juices,in an attempt to understand the in planta enzymatic process.2.Evidence supporting in planta anthocyanin degradationAnthocyanins often accumulate transiently,appearing and disappearing during plant development or with changes in environmental conditions[16].Several examples in which anthocyanins are degraded in plants are described below.2.1.Degradation during development2.1.1.Loss of red pigmentation in young foliage as it maturesAnthocyanins often accumulate in young/juvenile leaves,and degrade as the leaves mature[16].Since anthocyanins absorb light in both the visible and UV region,their accumulation in young developing foliage may serve as a‘sunscreen’,protecting the leaves,and in particular their photosynthetic apparatus,from damaging UV light as well as from photoinhibitory high intensities of visible light[17].These pigments may also provide antioxidant activity,protecting the cells from oxidative damage[18].As the leaves mature and form protective waxes that reﬂect sunlight, thereby providing a photoprotective function[19],they often change color from red to green.This loss of red pigmentation may be due to a combination of increased chlorophyll accumulation during leaf expansion and growth,termination of anthocyanin biosynthesis and dilution by growth,and/or increased actively induced anthocyanin degradation when it is no longer required as a photoprotectant.Anthocyanin degradation is apparent in greening of Chrysobalanus icaco(cocoplum)(Fig.1A)and Photi-niaÂfraseri cv.Red Robin leaves as they mature.In both plants, anthocyanins degrade as the leaves develop,resulting in green foliage[20,21].In Photinia plants,anthocyanin concentration is directly related to the age of the leaf,with high concentrations in young leaves,and a gradual decrease in concentration as the leaves develop,due both to dilution and degradation,resulting in undetectable concentrations of anthocyanins in the mature foliage [21].In cocoplum,the decrease in anthocyanin concentration as the leaves mature is due in part to dilution of the pigments intheFig.1.Anthocyanin degradation during development ofﬂowers,fruit and foliage.(A)Degradation in developing leaves of Chrysobalanus icaco.(B)Degradation in pepper (Capsicum annuum)mutant5226from mature unripe fruit(4)to ripe fruit(5).The Capsicumﬁgure was slightly altered from Fig.3of Borovsky et al.[19]with the kind permission of Springer Science+Business Media.(C)Degradation in Brunfelsia calycinaﬂowers from the day ofﬂower opening(0)until3days after opening(3).Values are means of four replicationsÆSE.The relative anthocyanin concentration is described by either a spectrophotometric reading at530nm(A)or the absorption-peak area of the pigments,when separated by HPLC on an RP-18column(B and C).M.Oren-Shamir/Plant Science177(2009)310–316311growing tissues and in part to actual degradation [20].In other plants,such as rose,the change in foliage color from young red to mature green leaves does not involve anthocyanin degradation and is due only to increased chlorophyll synthesis,termination of anthocyanin synthesis and dilution of the anthocyanins in the expanding leaves (unpublished,Liat Shahar).2.1.2.Anthocyanin degradation in developing fruitTransient accumulation of anthocyanins is seen in some fruits.One example is Capsicum spp.in which several lines accumulate anthocyanins in immature fruit and degrade them as the fruits mature [22,23](Fig.1B).Anthocyanins may accumulate and protect the photosynthetic apparatus in the developing fruit.As the Capsicum fruit matures,the anthocyanins in the vacuoles are degraded while chlorophyll degradation in the plastids and the synthesis of carotenoids result in the red,orange and yellow colors of the mature pepper fruit.Anthocyanin degradation is also observed in Sicilian sweet orange varieties,known as blood oranges (Tarocco,Moro e Sanquinello).The pigments accumulate in both the rind and ﬂesh of the fruit resulting in these varieties’characteristic red color.However,at the late stages of ripening,anthocyanin degradation is observed,resulting in a commercially undesirable partial loss of this color [24].2.1.3.Anthocyanin degradation in developing ﬂowersFlowers often change color during development,acting as a signal for pollinators.In most cases,the change in color is due to induction of anthocyanin synthesis,but in others,such as Brunfelsia calycina ,anthocyanin is degraded,resulting in a change of ﬂower color from dark purple to white after anthesis [25](Fig.1C).Further details on anthocyanin degradation in Brunfelsia are described later.The fading Fa mutants of petunia,lose color during ﬂower development [26,27].However,the change in color in Fa mutants is not due to anthocyanin degradation,but rather to a change in the vacuolar pH resulting in a change of anthocyanin hue and loss of visual coloration with no change in pigment concentration.2.2.Degradation due to changes in environmental conditions Anthocyanin concentration in foliage is tightly dependent on environmental conditions such as light quality,light intensity and growth temperature.Foliar anthocyanin accumulation is induced at high light intensities,in particular high UV light,and low growth temperatures [16].This process is often reversible,with greening of red foliage and stems when growth conditions change to low light intensity and warmer temperatures.The dark red pigmenta-tion of both the young and mature leaves of the garden plant Cotinus coggygria ‘Royal Purple’,occurs only with both low temperatures ( 178C/98C day/night respectively)and high UV irradiation [28,29].Anthocyanins of red Cotinus plants,grown at low temperatures,are degraded and their foliage turns green whencovered with a UV screen.Similarly,anthocyanin degradation occurs in red-pigmented plants when the temperature is elevated but UV radiation remains high [28,29](Fig.2A).The dependence of anthocyanin concentration on environmental conditions was also demonstrated in Arabidopsis thaliana plants transformed to over-express the transcription factor PAP1(Produc-tion of Anthocyanin Pigments 1)[30].The mutated arabidopsis plants were dark red under room temperature and high light conditions (228C,440m mol m À2s À1),but when transferred to conditions of high temperature and low light conditions (308C,150m mol m À2s À1)the plants turned green.The change in color was due to the simultaneous down-regulation of synthesis and degradation of the anthocyanins.These results suggest that there are additional mechanisms involved in the environmental control of anthocyanins,one of which may be controlled degradation [30].Anthocyanin pigmentation also ﬂuctuates in fruits in response to environmental conditions such as growth temperature and light intensity.An increase in growth temperatures causes preharvest degradation of anthocyanins and a signiﬁcant decrease in the fruit’s market value in both red pears and apples [31].Rapid anthocyanin degradation has also been reported in ‘Rosemarie’and ‘Forelle’pears,still attached to the tree,when the fruits were covered with light-impermeable bags [32](Fig.2B).2.3.Is anthocyanin turnover in plants dependent on environmental conditions?In addition to speciﬁc degradation of anthocyanins due to either developmental or environmental changes,there may be turnover of the pigments in plant tissue,even when no visual change in color is observed.The turnover of anthocyanins in living plant tissues has been followed using various techniques.Pulse-chase treatment of mustard seedlings with radioactive phenylalanine revealed a constant turnover of the pigments after reaching a high and steady level of anthocyanins [33].The turnover rate of anthocyanins was also followed by treating plant tissues with a speciﬁc phenylala-nine ammonia-lyase (PAL)inhibitor (aminooxyphenylpropionic acid—AOPP)preventing biosynthesis of the pigments:in petunia,low degradation levels were detected at speciﬁc developmental stages,while in carrot cells,no anthocyanin turnover was detected [34,35].Increased anthocyanin turnover in detached Cabernet Sau-vignon grape skin was seen at elevated growth temperatures [36].The ratio between the anthocyanins comprising Cabernet Sauvignon grape skin color varied,with less degradation of the methylated and acylated pigments [36].This is consistent with the ﬁnding that methoxylation,glycosylation and acylation increase the thermal stability of anthocyanins [37].This ﬁnding suggests that the low levels of anthocyanin observed in many plants when grown at elevated temperatures may be a combina-tion of a slower rate of biosynthesis [38–40]and increased catabolism.The catabolic process may be due either to chemical instability of the pigments or to speciﬁc enzymaticactivityFig.2.Anthocyanin degradation due to environmental changes.(A)Cotinus coggygria ‘Royal Purple’mature leaves from plants grown at 178C/98C day/night (leaves on left)and transferred to 298C/218C day/night (leaves on right)temperature conditions.(B)‘Rosemarie’pear fruit covered with a two-layered ‘Fuji’apple wrapping bag (Kobayashi Bag Mfg.,Nagano,Japan),for 0(pear on the left),1,2,3and 4(pear on the right)weeks.Photograph was kindly provided by Dr.Wiehann Steyn,Dept.of Horticultural Science,Stellenbosch University,South Africa.M.Oren-Shamir /Plant Science 177(2009)310–316312decreasing the pigment concentration in plant tissues,often in parallel to the synthesis process.Metal ions such as magnesium,manganese,tin and copper affect the stability of anthocyanins[2].These metals accumulate in the vacuoles and form stable complexes with the anthocyanins, thereby affecting their hue and increasing their stability[2].Stable complexes of magnesium ions with anthocyanins have been isolated from Hydrangea sepals[41].This phenomenon can be exploited to increase anthocyanin concentration in plants under environmental conditions in which the rates of synthesis are low.For example, treatment of Asterﬂowers with magnesium salts during the synthesis of anthocyanins caused an increase in pigment concen-tration in theﬂowers,without inducing the activity of several of the key enzymes along the biosynthetic pathway[42].This suggests that there is constant turnover of anthocyanins in the asterﬂowers,and magnesium treatments slow this process by stabilizing the pigments.Magnesium treatment has a similar effect on other ornamentals,increasing anthocyanin concentration in Anigozanthos, Limonium,Gypsophila and Aconitumﬂowers grown at elevated temperatures[43].3.Enzymatic degradation of anthocyaninsSome of the examples presented above suggest that the anthocyanin degradation process is controlled and induced when beneﬁcial to the plant,such as in the loss of foliar pigmentation as the leaves mature[20,21]or when light intensity decreases[32], allowing more light to be available for photosynthesis.In other examples,such as in Cabernet Sauvignon grapes,anthocyanin degradation does not result in a dramatic change in color as the pigments continue to be synthesized in parallel to their catabolism [36].In this case,the degradation may be due to lower chemical stability of the pigments at elevated temperatures.The question still remains as to whether degradation is due to enzymatic activity and whether degradation can be speciﬁcally induced as part of a complex system for controlling plant pigment concentration. Enzymatic studies of anthocyanin degradation in postharvest fruit and fruit juices have revealed several enzymes that degrade anthocyanins in these systems and may be candidates for active in vivo degradation.3.1.Anthocyanin degradation in fruit after harvestAnthocyanin degradation due to changing environmental conditions has been observed in fruit after harvest.One example of this is anthocyanin degradation in red-skinned pears and apples when the fruit are stored in warm(>108C)temperatures[32].This is similar to the effect of increased growth temperature on the pigmentation of red-skinned pears while still attached to the tree [32].The search for anthocyanin-degrading enzymes was performed on postharvest fruit,because of the market value of high pigmentation.Postharvest fruit is intermediate between the fruit still attached to the tree and the in vitro systems of fruit juices: postharvest fruit still carry out many of the enzymatic processes occurring before harvest.Intracellular decompartmentation and cell layer reparation begins during storage,and the pigments may be exposed to microenvironmental conditions that differ from those in planta,including enzymes that are not located in the vacuoles when the plant cells are intact.Anthocyanins in litchi fruit are degraded after harvest, accompanied by fruit browning[44–48].This change in color lowers the commercial value.Polyphenol oxidase(PPO)and peroxidase are thought to be responsible for the anthocyanin degradation in litchi.Peroxidase activity initially increases in the exocarp and during longer-term storage in the endocarp,while PPO activity increases during long-term storage in the exocarp [44–48].Treatment of the fruit after harvest with oxalic acid, known to reduce PPO activity by binding with the active sites of copper to form an inactive complex[49],reduces oxidation levels in litchi fruit and helps maintain low peroxidase activity and delay anthocyanin degradation[48].Postharvest loss of red color has also been detected in eggplant [50].In eggplant fruit subjected to chilling injury,browning with concomitant vacuolar disruption,electrolyte leakage,increased pH and decreased anthocyanin concentration were observed in the skin tissue[50].A b-glucosidase was extracted from eggplant peels that were capable of degrading anthocyanins[51].3.2.Enzymatic degradation of anthocyanins in fruit juicesThe most detailed studies on anthocyanin stability and degradation have been carried out with fruit extracts.These studies form the basis for understanding the processes leading to pigment loss in both postharvest fruit and in juices and wine.One of the main enzyme groups that oxidize anthocyanins in fruit extracts is the PPOs.These ubiquitous enzymes in higher plants are located in the plastids of both photosynthetic and non-photosynthetic tissues[52].Both PPO in conjunction with phenolic extracts[53]and anthocyanin b-glucosidase[54]are able to degrade the pigments in ethanolic extracts from the lichti fruit periderm in vitro.It was proposed that anthocyanins areﬁrst hydrolyzed by an anthocyanase(b-glucosidase),forming antho-cyanidin[53].These compounds can then be oxidized by PPO and/ or peroxidase.Oxidative products of phenolics,such as4-methylcatechol,resulting from PPO activity may then accelerate anthocyanin degradation via a coupled oxidative reaction[55]. Furthermore,PPO can oxidize anthocyanin degradation products resulting in tissue browning.PPO activity is the main factor responsible for anthocyanin degradation in juice prepared from red muscadine grapes(Vitis rotundifolia cv.Noble).Treating the juice with increased CO2 pressure(dense-phase CO2processing)partially inhibited PPO and decreased the rate of degradation of anthocyanin,as well as that of other polyphenolic compounds,during refrigerated storage[56].A speciﬁc b-glucosidase was isolated from the fruit juice of Tarocco Sicilian blood oranges and anthocyanin degradation kinetics was followed physiochemically[24].This enzyme is responsible for the degradation of anthocyanins in both the juice and the ripening fruit[24].In the presence of chlorogenic acid or caffeoyltartaric acid,PPO increased the rate of anthocyanin degradation in both grape and blueberry extracts and juices[57–60].PPO also degrades anthocyanins during the drying of plums in the presence of chlorogenic acid[61].Plastid located PPOs are not likely to degrade vacuolar anthocyanins in living tissue unless decompartmentation occurs.The peroxidases also degrade anthocyanins in fruit extracts, under mildly oxidizing conditions provoked by exogenous application of H2O2.A peroxidase isolated from a Gamay grapevine cell culture degraded anthocyanins in solution and was suggested to do so in the grape fruit as well[62].Peroxidases are also involved in the degradation of anthocyanins,resulting in loss of color in processed strawberries[63].Exogenous application of H2O2on strawberry slices caused a more rapid decrease in anthocyanin concentration during aging relative to non-treated slices,suggest-ing the involvement of peroxidase in this process.A proposed scheme summarizing the enzymatic processes involved in anthocyanin degradation is presented in Fig.3.Since peroxidases are present in cell vacuoles[64],unlike the oxidizing PPO enzymes, they are more likely candidates for in planta anthocyanin degradation.M.Oren-Shamir/Plant Science177(2009)310–3163133.3.Active in planta degradation of anthocyaninsEvidence has been presented of in planta degradation of anthocyanins in ornamentals and fruits.We have also outlined extensive studies on enzymatic anthocyanin degradation in fruit extracts,juices and wine.However,until recently,it was not known if anthocyanin degradation in intact plants involves active enzymatic or merely chemical reactions.Active anthocyanin degradation was ﬁrst reported in living plant tissue of Brunfelsia calycina ﬂowers.Brunfelsia ,a shrub in the Solanaceae family is native to Brazil,and is an ideal model plant for studying anthocyanin degradation because of the dramatic and rapid color changes occurring within 2–3days after ﬂower opening (Fig.1C).This loss of color from dark purple to white is dependent on anthocyanin degradation and de novo synthesis of mRNAs and proteins during the different stages of development,well before the start of ﬂower senescence [25].An additional advantage of this model system is that the same dramatic decrease in pigment concentration occurs in ﬂowers detached on the day of ﬂower opening and grown in a sucrose solution [25].Similar to what has been shown in fruit juices and wine,oxidative reactions are crucial for anthocyanin degradation in Brunfelsia ,since treatment of detached ﬂowers with the reducing reagents dithio-threitol (DTT)or glutathione inhibit degradation [25].Assuming that in planta anthocyanin degradation occurs in the cell vacuoles,oxidizing enzymes found in the vacuole,such as peroxidases are more likely candidates than those accumulating elsewhere in the cells,such as PPO located in the plastids.A dramatic increase of total peroxidase activity was detected in correlation with the onset of anthocyanin degradation in Brunfelsia ﬂower petals,strengthening the notion that these enzymes are involved in the process [25].Nevertheless,the possibility that anthocyanins are transferred out of the vacuoles before degradation exists and further studies are needed to determine the site of degradation.The b -glucosidases may also be involved in the in planta degradation process,since they increased the degradation rate of anthocyanins in fruit extracts of both litchi and eggplant [51,54].D -Gluconic acid,a speciﬁc b -glucosidase inhibitor,signiﬁcantly decreased the rate of degradation in Brunfelsia ﬂowers (unpub-lished,Hila Vaknin and Raya Liberman).One possible explanation is that b -glucosidase activity precedes the oxidation reaction with peroxidase as a candidate oxidizing enzyme.Stripping the anthocyanin molecules of their glucose residues may enable better access for the peroxidase enzyme and faster degradation.Hence,it is likely that anthocyanin degradation is a complex process involving more than one enzyme.4.Concluding remarksAnthocyanin degradation occurs in different plant organs due to a variety of environmental and developmental conditions.In some cases,where there is no apparent beneﬁt to the plant,anthocyanin degradation occurs due to changes in the vacuoles that decrease the stability of the pigments and cause either chemical degradation or increased vulnerability to degrading enzymes (e.g.b -glucosi-dases,peroxidases)present in the vacuoles.For example,the degradation of anthocyanins in Cabernet Sauvignon grape skin exposed to high temperatures may be due to chemical degradation,but may also be a product of the activity of peroxidase enzymes induced due to the thermal stress [36].A second example is the effect of vacuolar pH on the stability of the pigments.Changes in the vacuolar pH,such as increased pH in senescing tissue,may decrease the stability of the anthocyanins and cause chemical degradation [2].In other cases,such as in Brunfelsia ﬂowers or in photosynthetic tissues,there are clear reasons why the degradation of anthocya-nins beneﬁts the plant.In these cases the process may be regulated by and dependant on speciﬁc genes and proteins.InBrunfelsiaFig.3.Proposed scheme describing anthocyanin degradation and tissue browning in fruit extracts.POD,peroxidase;PPO,polyphenol oxidase.POD is dependant on H 2O 2for its activity while PPO is dependant on O 2.Three alternative pathways for enzymatic anthocyanin degradation are presented.(1)Coupled oxidation,i.e.reduction of quinones of phenolic compounds to the original phenolic compounds in parallel to oxidation of anthocyanin to anthocyanin quinone.(2)Degradation in two steps:de-glycosylation with anthocyanase (b -glucosidase)and then oxidation with polyphenol oxidase or peroxidase.(3)Direct oxidation of anthocyanin with peroxidase.M.Oren-Shamir /Plant Science 177(2009)310–316314calycinaﬂowers,the dramatic change in color due to anthocyanin degradation is most probably a signal for the pollinators and is regulated at the gene and protein levels[25].In photosynthetic leaves,since anthocyanin accumulation decreases their photo-synthesis rate but protects the tissue from free radical scavenging [65],degradation under low light and high temperatures will enable more efﬁcient photosynthesis under conditions that are not prone to photo-oxidation.Revealing the different catabolic processes occurring in plants may allow for improved treatments that control plant tissue color. Increased stability of the pigment molecules may be achieved either by treatments such as increasing the concentration of the stable metal–anthocyanin complexes[42],or molecular manip-ulation of the pigments to form more stable anthocyanins. 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紫色乌塌菜与传统乌塌菜农艺性状与营养品质比较

紫色乌塌菜与传统乌塌菜农艺性状与营养品质比较作者：邱婷婷王兵帆郝加敏周贺芳来源：《西北园艺·蔬菜》2024年第02期摘要淮南市农科院选育的紫色乌塌菜品种“NKHXW281”“NKHXW297”富含花青素。

对比了这两个品种和传统黄心品种“淮南精品塌地乌（CK1）”和“淮南塌地乌8号（CK2）”農艺性状和营养品质。

结果表明，紫色乌塌菜在株高和开展度方面显著高于对照组，富含可溶性糖、蛋白质等营养元素，而且含有大量花青素，满足了现代人对健康的需求。

关键词紫色乌塌菜;农艺性状;营养品质;花青素不结球白菜（Brassica campestris ssp. chinensis）属于十字花科芸薹属，是其中3个亚种之一。

过去的研究已证明不结球白菜可以细分为6个变种，乌塌菜是其中之一。

乌塌菜以其独特的外观、很好的耐寒性、富含维生素和膳食纤维而受到广大消费者喜爱，并在江淮流域得到广泛种植。

随着人们生活质量的提高，传统黄心乌已无法满足大众需求，具有高品质和高观赏性的乌塌菜品种选育成为研究的热门方向。

在蔬菜育种过程中，花青素因其特殊的生理功能，逐渐被育种者重视。

这种天然色素不仅能有效清除人体自由基，对抗衰老，还有助于调节血糖、缓解眼疲劳、抑制过敏、抗炎和抗癌。

此外，花青素也在植物自身防御中扮演关键角色，尤其是在提高植株抗寒能力和保护植物免受紫外线伤害方面。

基于上述需求，淮南市农科院利用传统育种技术培育出“NKHXW281”和“NKHXW297”两个紫色乌塌菜品种。

本研究主要探讨这两个新品种与传统黄心乌塌菜品种在农艺性状和营养品质上的差异，以期选育推广更符合江淮地区需求的紫色乌塌菜，并为培育高花青素乌塌菜提供有价值的遗传资源。

1 材料与方法1.1 试验材料选择淮南市农业科学研究院新选育的“NKHXW281”和“NKHXW297”作为试验材料，同时选取“淮南精品塌地乌（CK1）”和“淮南塌地乌8号（CK2）”作为对照。

植物花青素生物合成途径相关基因研究进展及其基因工程修饰

植物花青素生物合成途径相关基因研究进展及其基因工程修饰赵德勇【摘要】This paper reviews the advances in research of synthetic genes and regulator genes involved in the anthocyanin biological synthesis process as well as in genetic engineering in regulating the anthocyanin biological synthesis. Anthocyanin biological synthesis process of plants belongs to the secondary metabolic pathway, regulates the expression of key enzymes involved in the pathway, and could hence lead to a reducedor increased yield of target compound. Genetic improvement of plants may be realized through modifying the secondary metabolic process. Anthocyanin accumulation helps the plants to act against the UV Further study on the defense molecular mechanism of the anthocyanin facilitates b with resistance to diseases and adversities. radiation, insects and fungi. reeding of new plant cultivars%对植物花青素生物合成及调控基因的研究进展、基因工程在调控花青素合成途径中的应用进行了综述。

不同盐度对冰菜生长和色素积累的影响

1材料与方法
1.1试验材料试验于2016年3〜5月在温州市种子种苗科技
园进行，所用冰菜引自山东寿光，海水晶（广东省徐闻盐场速溶海水晶厂）购置温州浙南农贸市场。 1.2试验方法
挑选生长健壮、均匀一致的冰菜幼苗25株置于等量同一基质中进行盆栽（d=13 cm, h=12 cm）,用海水晶配制6%o、12%o、24%o和3O%o共4个浓度盐溶液，以清水做空白对照（CK）。每个处理5株冰菜, 置于同一潮汐盘中，共计5个处理。3月31日开始, 各处理分别浇灌相应处理液至盆底有渗出。每周处
目前，有关冰菜的研究主要集中在盐胁迫信号和作用机制方面⑶，不同盐度下其生长表现和色素
基金项目：温州科技职业学院农技推广项目(NJTG201602) 第一作者：史建磊(1982—),男,河北张家口人，硕士，研究方向为蔬菜遗传育种。
史建磊，苏世闻，周友和，等：不同盐度对冰菜生长和色素积累的影响
21
积累情况少见报道。本研究以盆栽冰菜为试材，通过测定其在不同盐度下的形态指标、生物量和色素含量，初步确定其温州栽培适应性及适宜盐度水平，旨在为其地区推广应用提供参考。
SHI Jianlei, SU Shiwen, ZHOU Youhe, HUANG Zongan (Wenzhou Vocational College ofScience and Technology, Wenzhou 325006, China)
Abstract: In order to speed up the utilization of new salt-tolerant vegetables, potted ice plants were used to study the morphological characters, biomass, and pigment contents with different salinities. The results showed that the number of leaves, leaf size, plant height, and root length of ice plants were 25%, 52.8%, 75.7%, 21.7% and 23.6%, higher than that of the control, respectively; the dry weights and fresh weights of stems and leaves were 2.35 and 4.03 times of that of the control; the anthocyanin content was 3.56 times of that of the control. It indicated that suitable salinity promoted the growth of ice plants, focused on plant height, increased branching, leaf size, root elongation, stem and leaf biomass and anthocyanin accumulation, but inhibited root biomass and chlorophyll accumulation. The optimum salinity was 6%o-12%o, and a high salinity greater than 30%o caused a stress effect.

番茄SlNAM1_参与调节植物花青素累积

2023 ，43（3） : 001J.SHANXI AGRIC, UNIV . （ N atural Science Edition ）学报（自然科学版）04189番茄SlNAM1参与调节植物花青素累积柳芳艳，张苹，郭慧敏，宋倩倩，孙亮亮*，徐进*（山西农业大学园艺学院，山西晋中 030801）摘要：［目的］探究番茄SlNAM1参与调节花青素累积的分子机理，深入理解植物花青素积累的调控机制。

［方法］通过酵母双杂交实验，检测番茄SlNAM1和SlMYB75、拟南芥NAC32与MYB75/PAP1蛋白相互作用；构建系统发育树，进行SlNAM1序列分析；通过烟草叶片瞬时表达分析，初步探明SlNAM1在调节植物花青素积累中的作用；在拟南芥pap1⁃D 突变体中过表达SlNAM1，研究SlNAM1在调节植物花青素积累中的作用；通过对拟南芥pap1⁃D NAC32OX （OX32）双突变体表型分析，进一步证明SlNAM1的拟南芥同源基因NAC32参与调控花青素积累。

［结果］酵母双杂交结果显示，SlNAM1与SlMYB75蛋白存在相互作用，其在拟南芥中的同源基因NAC32与MYB75/PAP1也存在相互作用；瞬时表达分析表明，SlNAM1通过与SlMYB75的相互作用，抑制了花青素积累；在拟南芥pap1⁃D 突变体中过表达SlNAM1可抑制花青素累积；拟南芥pap1⁃D OX32双突变体表型分析结果表明，NAC32过表达抑制了花青素积累。

［结论］综上所述，SlNAM1是花青素合成的负调节因子。

关键词：番茄； SlNAM1； SlMYB75； NAC32；花青素中图分类号：S641.2 文献标识码：A 文章编号：1671-8151（2023）03-0001-08NAC 转录因子家族是植物体内特有的、最大的转录因子家族之一，它是以最早发现的基因成员矮牵牛无根分生组织（NAM ）、拟南芥ATAF1、ATAF2及杯状子叶2（CUC2）的首字母来命名的［1］。

‘北玫’‘北全’葡萄果实中酚类物质比较

332023.6SINO-OVERSEAS GRAPEVINE & WINE‘北玫’‘北全’葡萄果实中酚类物质比较邵洁玲，单守明，马军，雷昊，李亚川，刘成敏*（宁夏大学农学院，宁夏银川 750021）摘要：以贺兰山东麓红色酿酒葡萄免埋土品种‘北玫’和‘北全’为试材，结合主成分（PCA ）和正交偏最小二乘判别分析（OPLS-DA ）统计学分析，明确果实发育中4个时期单体酚以及采收期酚类物质含量的差异。

结果表明，两个品种单宁和花色苷在成熟过程中变化趋势接近，总酚含量积累趋势两者有所不同。

黄烷醇类化合物为采收期的主要单体酚，其中黄烷醇、酚酸、黄酮醇类化合物总量均是‘北全’高于‘北玫’，分别是1.18倍、1.13倍和1.32倍，其主要成分分别为儿茶素、绿原酸和芦丁；两品种白藜芦醇含量均呈先上升后下降的趋势，但在转色期间‘北玫’高于‘北全’，而成熟期和采收期为‘北全’显著高于‘北玫’。

PCA 和OPLS-DA 分析表明，黄烷醇类为主要差异物质，与显著性分析结果一致。

本研究通过对不同品种酚类物质进行比较分析，发现‘北全’较‘北玫’潜力更大。

关键词：北玫；北全；葡萄果实；酚类物质中图分类号：S663.1 文献标志码：A DOI ：10.13414/ki.zwpp.2023.06.005收稿日期：2023-02-20基金项目：宁夏回族自治区农业育种专项（NXNYYZ20210102）作者简介：邵洁玲（1997—），女，硕士，主要从事园艺植物生物学与组培研究。

E-mail:******************通信作者：刘成敏（1964—），研究员，主要从事园艺植物生物学等研究工作。

E-mail:****************Comparison of Phenolic Substances in 'Beimei' and 'Beiquan' Wine GrapesSHAO Jieling, SHAN Shouming, MA Jun, LEI Hao, LI Yachuan, LIU Chengmin*(College of Agriculture, Ningxia University, Yinchuan 750021, China)2023(6): 33-39Abstract: Using non-buried red wine grape varieties 'Beimei' and 'Beiquan' from the eastern foot of HelanMountains as test materials, the content of individual phenolic substances during the four stages of fruit development and the phenolic substances during harvest were measured, and statistical analysis was conducted using principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA). The results showed that the changes of tannin and anthocyanins in the two varieties during ripening were similar, while the accumulation trend of total phenol content was diﬀerent. Xanthanols were the main monomeric phenols during the harvest period, and the total content of xanthanols, phenolic acids, and ﬂavonols were 1.18, 1.13, 1.32 times higher than that of 'Beimei'. The main components were catechin, chlorogenic acid, and rutin, respectively; The resveratrol content of two varieties increased ﬁrst and then decreased, but the content of resveratrol in 'Beiquan' was higher than that in 'Beiquan' in veraison period, and the content of resveratrol in 'Beiquan' was higher than that in 'Beimei' at the maturity and harvesting stage. PCA and OPLS-DA analysis showed that ﬂavanols were the main diﬀerence substances, consistent with the signiﬁcance analysis results. Through comparative analysis of phenolic substances in diﬀerent varieties, this study found that 'Beiquan' variety has more potential than 'Beimei' variety.Key words: Beimei; Beiquan; grape fruit; phenolicsSINO-OVERSEAS GRAPEVINE & WINE酚类物质是酿酒葡萄果实中重要的功能成分，由一系列次生代谢产物构成，受葡萄品种、栽培条件和成熟度等因素影响[1]。

李韶山教授简介

李韶山教授简介李韶山，广东省珠江学者特聘教授。

1992年在华南师范大学获理学博士学位；曾留学瑞典Lund University和Örebro University以及美国College of William & Mary。

现任华南师范大学生命科学学院副院长，生态学专业博士生导师。

多年来从事植物生理生态学研究，主要研究方向是植物紫外辐射（UV-B）效应的细胞和分子机理研究、植物对重金属污染的分子响应和生态毒理、微生物与植物根系的相互作用、以及入侵植物的生态适应性和比较基因组学研究。

已主持承担多项国家自然科学基金、教育部博士点基金、教育部留学回国人员科技项目以及广东省高层次人才项目等。

在国际、国内重要学术刊物发表的代表性论文（标注*为通讯作者）：1.Jiang Lei, Wang Yan, Li Qianfeng, Björn LO, He Junxian, Li Shaoshan*.Arabidopsis STO/BBX24 negatively regulates UV-B signaling by interacting with COP1 and repressing HY5 transcriptional activity.Cell Research, 2012, 22:1046-1057 (IF=10.526)2.Qin Rong, Zhang Huaning, Li Shaoshan, Jiang Wusheng, Liu Donghua*. Threemajor nucleolar proteins migrated from nucleolus to nucleoplasm and cytoplasm in root tip cells of Vicia faba L. exposed to aluminum. Environmental Science and Pollution Research, 2014, 21: 10736-10743（IF=2.681）3.Gong Ni, Wang Yutao, Björn L O, and Li Shaoshan*. DNA C-values of 20invasive alien species and 3 native species in south China. Archives of Biological Sciences, 2014, 66(4): 1465-1472 (IF=0.607)4.Chen Yong, Zou Shenshen, Zhou Fan, Yu Sidney, Li Shaoshan, Li Dan, SongJingzen, Li Hui, He Zhiyi, Hu Bing, Björn L O, Liang Yongheng*, Xie Zhiping, Segev Nava*. A Vps21 endocytic module regulates autophagy. Molecular Biology of the Cell, 2014, 25: 3166-3177 (IF=4.548)5.Zou Shenshen, Chen Yong, Liu Yutao, Segev N, Yu S, Ye Min, Zeng Yan, MinGaoyi, Zhu Xiaoping, Hong Bing, Björn LO, Liang Yongheng*, Li Shaoshan*, Xie Zhiping*.Trs130 and Trs65 regulate autophagy through GTPases Ypt31/32 in Saccharomyces cerevisiae.Traffic 2012, , DOI: 10.1111/tra.12024 (IF=4.919)6.Chen Da, Wang Yan, Yu Lehuan, Luo Xiaojun, Mai Bixian, Li Shaoshan*. 2013.Dechlorane plus flame retardants in terrestrial raptors from northern China.Environmental Pollution, 2013, 176: 80-86 (IF=3.746)7.Björn LO*, Li Shaoshan. Teaching about photosynthesis with simple equipment:Analysis of light-induced changes in fluorescence and reflectance of plant leaves.Photosynthesis Research, 2013, 116: 349-353 (IF=3.243)8.Björn LO*, Uvdal P, and Shaoshan Li. Ecological importance of the thermalemissivity of avian eggshells. Journal of Theoretical Biology, 2012, 301: 62-66 (IF=2.371)9.Jiang Lei, Wang Yan, Björn LO, Li Shaoshan*. UV-B-induced DNA damagemediates expression changes of cell cycle regulatory genes in Arabidopsis root tips. Planta, 2011, 233: 831-843 (IF=3.372)10.Wang Yan, Smith W, Wang Xiaodong, Li Shaoshan. Subtle biological responsesto increased CO2 concentrations by Phaeocystis globosa Scherffel, a harmful algal bloom species. Geophysical Research Letters, 2010, 37, L09604, DOI:10.1029/2010GL042666 (IF=3.204)11.Jiang Lei, Wang Yan,Björn LO, Li Shaoshan*. ArabidopsisRADICAL-INDUCED CELL DEATH1 is involved in UV-B signaling.Photochemical and Photobiolgy Sciences, 2009,8: 838-846 (IF=2.708)12.Kalbina I, Li Shaoshan, Kalbin G, Björn LO, Strid Å*. Wavelength dependenceof expression of UV-B-induced molecular markers in Arabidopsis thaliana.Functional Plant Biology, 2008, 35: 222-227 (IF=2.375)13.Jiang Lei, Wang Yan, Li Shaoshan*. Application of the comet assay to measureDNA damage induced by UV radiation in the hydrophyte, Spirodela polyrhiza.Physiologia Plantarum, 2007, 129: 652-657 (IF=2.708)14.Li Shaoshan, Kalbin G, Olsman H, Pettersson M, Engwall M, Strid Å*, Effects ofUV-B in biological and chemical systems: Equipment for wavelength dependence determination. Journal of Biochemical and Biophysical Methods, 2005, 65: 1-12 (IF=1.286)15.Li Shaoshan and Strid Å*, Anthocyanin accumulation and changes in CHS andPR-5 gene expression in Arabidopsis thaliana after removal of the inflorescence stem (decapitation). Plant Physiology and Biochemistry, 2005, 43: 521-525(IF=2.485)16.Li Shaoshan*, Wang Yan, Björn LO, Effects of temperature on UV-B-inducedDNA damage and photorepair in Arabidopsis thaliana. Journal ofEnvironmental Sciences, 2004, 16: 173-176 (IF=1.412)17.Li Shaoshan, Paulsson M, Björn LO, Temperature-dependent formation andphotorepair of DNA damage induced by UV-B radiation in suspension-cultured tobacco cells. Journal of Photochemistry and Photobiology, B: Biology, 2002,66 : 67-72 (IF=2.708)18.Li Shaoshan, Wang Yan, Wang Xiaojing, Bin Jinhua and Liu Songhao. CPDsaccumulation in relation to UV-B sensitivity in rice cultivars. Acta Botanica Sinica, 2000, 42 (6): 576-581 (IF1.395)19.汪骢跃†、王宇涛†、曾琬淋、李韶山*，钙和钾对拟南芥幼苗镉毒害的缓解作用。

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Original articleAnthocyanin accumulation and changes in CHS and PR-5gene expression in Arabidopsis thaliana after removalof the inﬂorescence stem (decapitation)Shaoshan Li a,b ,Åke Strid a,*aDepartment of Natural Sciences,Örebro Life Science Center,Örebro University,70182Örebro,SwedenbSchool of Life Science,South China Normal University,Guangzhou 510631,ChinaReceived 3January 2005;accepted 10May 2005Available online 06June 2005AbstractAnthocyanin accumulation occurs in rosette leaves of Arabidopsis thaliana within 8days after removal of the inﬂorescence stem.Expres-sion of stress-induced genes CHS and PR-5was strongly up-regulated by stem removal,and was highest on day 4after decapitation.These levels were 10and 5times higher than in the control,respectively.No obvious difference was found in expression of LHCB ,MEB5.2,or PYROA genes following stem removal.We demonstrate that removing the inﬂorescence stem triggers events in Arabidopsis ,including pig-ment accumulation and changes in gene expression of a subset of stress-induced genes,in a tissue distant from the wound site.©2005Elsevier SAS.All rights reserved.Keywords:Anthocyanins;Arabidopsis thaliana ;Decapitation;Gene expression;Real-time RT-PCR;Wounding1.IntroductionGrowth and differentiation of shoot apical meristem are fundamental components of plant physiology,and play impor-tant roles in plant development.It has been known for a long time that the existence of apical buds in dicot plants is respon-sible for apical dominance [11].Kotova et al.reported changes in phytohormone status in stems and roots after decapitation of pea seedlings.The IAA level in the internodes decreased two to threefold on the second day after decapitation of seed-lings,while the cytokinin level increased 56-fold for zeatin and zeatin riboside [10].Many of the molecular events involved in decapitation of plants remain unknown.In the present study we examined changes in pigment levels and regulation of stress genes as a result of removing the inﬂo-rescence stem in Arabidopsis thaliana .It has been reported that anthocyanin accumulation in many plants can be induced by biotic and abiotic stresses,such as UV-B radiation,drought,high or low temperature,and alsothat gene expression of stress genes is regulated by one or more stresses [3].For instance,UV-B radiation regulates a large number of genes in plants.These UV-B-regulated genes can be divided into different classes depending on the levels of stress needed to induce expression and on the temporal dependency of induction [3].These differences in expression pattern imply distinct signal transduction and regulation path-ways for the different classes of genes.Among UV-B regu-lated genes are those encoding chalcone synthase (CHS),pathogenesis-related (PR)protein,PYRO A and MEB5.2.CHS is the ﬁrst committed enzyme in ﬂavonoid and antho-cyanin biosynthesis.PYRO A is an enzyme involved in syn-thesis of vitamin B 6[2]as shown in yeasts and fungi.In turn,vitamin B 6has been shown to participate in detoxiﬁcation of reactive oxygen species thought to be formed during UV-B irradiation [3].MEB5.2,a gene encoding a protein of unknown function,is the gene most highly regulated by UV-B radia-tion out of 5000tested genes [2].In addition,most photosyn-thetic genes,such as those encoding light-harvesting com-plex proteins (i.e.LHCBs;Ref.[7]),are down-regulated by UV-B.Such a set of molecular markers are therefore infor-mative to use when comparing gene expression stress regu-lation mechanisms.*Corresponding author.Tel.:+4619303603;fax:+4619303566.E-mail address:ake.strid@nat.oru.se (Å.Strid).Plant Physiology and Biochemistry 43(2005)521–525/locate/plaphy0981-9428/$-see front matter ©2005Elsevier SAS.All rights reserved.doi:10.1016/j.plaphy.2005.05.004We here report the strong accumulation of anthocyanins and the changes in gene expression of molecular stress mark-ers induced by removing the inﬂorescence stem in A.thaliana .2.ResultsEight days after cutting the inﬂorescence stem,the whole rosettes of Arabidopsis plants had turned purple.In intact con-trol plants,only a faint purple color at the base of the petioles was apparent (Fig.1).Differential absorption spectra of acidi-ﬁed methanol extracts indicated peaks in the UV region and at 535nm,which is typical for anthocyanins (Fig.2A;Ref.[5]).Dramatic increase in the UV region in the differential absorption spectra also indicates accumulation of UV-absorbing compounds,possibly ﬂavonoids,by decapitation.Anthocyanins accumulated in decapitated Arabidopsis in a linear fashion between 2and 8days after removing the inﬂo-rescence stem (Fig.2B).Expression of the stress-induced CHS gene (At5g13930;encoding the enzyme chalcone synthase)and PR-5(At1g75040;encoding a PR protein)was greatly induced by removal of the inﬂorescence stem (Fig.3A,B).The relative transcript levels of CHS and PR-5increased continuously and reached the highest points on the fourth day after decapita-tion.Transcript levels of two other genes induced by abiotic stresses,PYROA (At5g01410;encoding a pyridoxin biosyn-thesis gene)and MEB5.2(At3g17800;encoding a protein with unknown function),remained constant during the week fol-lowing decapitation (Fig.3C,D).The mRNA levels of the photosynthetic LHCB gene (At1g29930;encoding a chloro-phyll a /b -binding protein of the photosystem II light-harvesting complex)were unchanged after decapitation (Fig.3E).3.DiscussionRemoval of the inﬂorescence stem in A.thaliana induced anthocyanin accumulation (Fig.1A,B).The exact function of anthocyanins after decapitation is not clear.However,among other roles,anthocyanins together with ﬂavonoids form in vegetative tissue to function as photoprotective radia-tion screening substances in order to attenuate high intensi-ties of solar radiation [18].For instance,UV-absorbing pig-ments accumulate in plants after UV-B exposure [15,19].Also,Fig.1.Anthocyanin accumulation in A.thaliana induced by removal of the inﬂorescence stem.(A)Left,intact plant as control;right,plant 1week after removing the inﬂorescence stem.(B)Above,detached leaves from decapi-tated plants;below,detached leaves from controlplants.Fig.2.(A)Differential absorption spectrum of extracts prepared from deca-pitated A.thaliana plants a week after removal of the inﬂorescence stem (sample)and control plants (reference).(B)Anthocyanin contents were deter-mined and given as A 535.Data show the means and standard errors of three independent biological repetitions.522S.Li,Å.Strid /Plant Physiology and Biochemistry 43(2005)521–525we have detected that the accumulation of anthocyanins in purple cultivars of lettuce (Lactuca sativa )is dependent on UV-B,since this accumulation does not occur in plants grown in growth rooms and since these varieties of lettuce grown outdoors under glass cover are green and not purple (Å.Strid,unpublished observation).Plants grown outdoors without glass cover,on the other hand,show strong anthocyanin accu-mulation.Therefore,the phenylpropanoid biosynthetic path-way,eventually leading to production of compounds includ-ing ﬂavonoids and anthocyanins,has an importantfunctionFig.3.Changes in gene expression in decapitated plants were measured by using real-time RT-PCR.(A)CHS ;(B)PR-5;(C)MEB5.2;(D)PYROA ;(E)LHCB .Plant rosettes were harvested during 5days following decapitation and used for RNA isolation.The data of the relative transcript levels were normalized to the expression of the 18S rRNA gene as internal control.Vertical bars correspond to standard errors of two independent biological repetitions with three different assays in each.523S.Li,Å.Strid /Plant Physiology and Biochemistry 43(2005)521–525in plants under environmental stress.Chalcone synthase is a key enzyme in this pathway,catalyzing theﬁrst committed step inﬂavonoid biosynthesis.CHS transcription is regulated by endogenous programmes in response to environmental stresses[1,3,8,9],such as high light,UV-B radiation,mechani-cal wounding and plant–microbe interactions.Our results also show that decapitation altered the expres-sion only of a subset(CHS and PR-5)ofﬁve stress-regulated genes.These differences show that the signal transduction pathways of CHS and PR-5regulation differ from those of the other three genes tested.This conﬁrms the conclusions regarding branched signal transduction pathways for regula-tion of molecular stress markers in plants[1,3].Components of the different stress speciﬁc and non-speciﬁc pathways are e.g.jasmonic acid,salicylic acid,ethylene,reactive oxygen species,calcium release,and phosphorylation events.Espe-cially,PR-5gene expression is regulated by alteration of hor-mone levels[1,3]and also seems to be modulated by brassi-nosteroids[16].The PR-5protein,a member of the PR proteins,is impli-cated in systemic plant defense against phytopathogenic fungi [17].The accumulation of PR proteins is triggered by patho-gen attack or abiotic stress.The functions of most PR pro-teins remain unclear but some of them have known function such as PR-5(fungal membrane permeabilizer)[6].The present results indicate that the level of PR-5mRNA tran-scripts in Arabidopsis leaves strongly increase as a result of decapitation and therefore PR induction protein is paralleled by increased secondary metabolism,as judged by increased CHS gene expression and accumulation of anthocyanins.Our results speciﬁcally show that removal of the inﬂores-cence stem activates expression of a subset of genes in the rosette leaves,i.e.distal from the wound site.In agreement with our present results,systemic accumulation of CHS mRNA in needle tissue of white spruce following wounding was reported[13].Also,pathogen challenge triggered a sys-temic or induced resistance in tissue remote to the initial infec-tion[14].Three other stress-regulated molecular markers were not affected by decapitation:1)PYROA,which was identiﬁed by DNA microarray analysis to be strongly regulated by UV-B radiation,is a gene encoding an enzyme required for biosyn-thesis of pyridoxine(vitamin B6)[2];2)MEB5.2,encoding a protein with unknown function,is a gene responsive to very low level of UV-B radiation stress[2];3)The photosynthetic LHCB gene,normally down-regulated by stresses[7],did not respond to decapitation either.In conclusion,the signal triggered by decapitation can be transduced to non-damaged tissue activating systemic expres-sion of wound-responsive genes such as CHS and PR-5, thereby inducing anthocyanin accumulation in rosettes of A. thaliana distal from the wound site.However,decapitation does not induce regulation expression of other stress-induced genes.It is therefore clear that a web of signal transduction or gene regulation pathways is present in plants to differen-tially and accurately control the transcription of stress-induced genes under different circumstances.4.Materials and methods4.1.Plants and growth conditionsSeeds of A.thaliana ecotype Columbia0(Col-0)were treated for a week at4°C after sowing on a peat/perlite/ vermiculite(1:1:1[v/v])mixture and then transferred to a growth chamber.Plant seedlings were grown in the chamber with photosynthetic active radiation(PAR,400–700nm)for 4weeks at100µmol m–2s–1,16h light(22°C)/8h dark (18°C)photoperiod at70%humidity.The plants began to ﬂower after4weeks.The inﬂorescence stem was cut at the base when it was about3cm in height,and branching shoots emerging after cutting the inﬂorescence stem were decapi-tated when they were1cm high.4.2.RNA isolation and real-time RT-PCRAll rosette leaves were harvested,frozen in liquid nitro-gen and stored at–80°C for RNA isolation.The RNA was isolated using Plant RNeasy Mini Kit(Qiagen,Germany), according to the manufacturer’s instructions.RNA was reversely transcribed using random hexamers(PdN6),RNase-OUT(recombinant ribonuclease inhibitor,Invitrogen)and SuperScript II RNase H–reverse transcriptase(Invitrogen) according to the manufacturer’s recommendations.The reac-tions were incubated at25°C for10min(primer annealing) and at42°C for50min(cDNA synthesis).Quantitative real-time RT-PCR[4,12]was performed with an ABI PRISM 7000Sequence Detection System(Applied Biosystems,Fos-ter City,CA).TaqMan primers and probes were designed by Primer Express2.x software(Applied Biosystems)accord-ing to the sequence provided in the TAIR database ().The sequences of primers and probes are listed in Table1.TaqMan Universal PCR Master Mix(Applied Biosystems)was used for real-time PCR,which was carried out in a MicroAmp Optical96-well plate with barcode.PCR reaction mixtures were subjected to the follow-ing thermal proﬁle:one step at50°C for2min,one step at 95°C for10min,40cycles with a denaturation step at95°C for15s and an annealing/extension step at60°C for1min. Each assay included triplicate reactions in the same plate. Assay-on-Demand(Applied Biosystems)was used for18S rRNA gene quantiﬁcation(internal standard)by real-time RT-PCR.The relative values of transcript levels were normal-ized to the total RNA content of the samples as represented by the corresponding quantiﬁcation of18S rRNA.4.3.Measurement of anthocyaninsFor spectrophotometric determination of anthocyanin con-tents,three0.9-cm diameter leaf discs were placed in1.5ml of acidiﬁed methanol(70%methanol;1%HCl v/v)and allowed to extract for48h at–20°C.Absorbance of the extracts was read at535nm.When measuring the differential absorption spectrum of pigments induced by decapitation524S.Li,Å.Strid/Plant Physiology and Biochemistry43(2005)521–525(Fig.2A),extract from leaves of control plants was used in the reference beam of the spectrophotometer. AcknowledgementsThis work wasﬁnancially supported by grants toÅ.S.from the Magn Bergvall Foundation and theÖrebro University’s Faculty for Medicine,Natural Sciences and Technology.S.L. was supported by the Natural Science Foundation of China (NSFC,Project No.30370126and No.30470283).S.L.was also awarded a scholarship by the Chinese Scholarship Coun-cil(CSC),Ministry of Education of China,to support his stay inÖrebro during this study.The authors wish to thank Irina Kalbina for her help with the real-time RT-PCR measure-ment.References[1]S.A.-H.Mackerness,Plant responses to ultraviolet-B(UV-B:280–320nm)stress:what are the key regulators?Plant Growth Regul.32 (2002)27–39.[2]M.Brosché,M.A.Schuler,I.Kalbina,L.Connor,Å.Strid,Generegulation by low levels of UV-B radiation:identiﬁcation by DNA array analysis,Photochem.Photobiol.Sci.1(2002)656–664.[3]M.Brosché,Å.Strid,Molecular events following perception ofultraviolet-B radiation by plants,Physiol.Plant.117(2003)1–10. 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