红罗宾石楠叶色变化及色素含量动态

Changes in color and pigment content of the Photinia×fraseri‘Red Robin’

研究红叶石楠叶色年变化规律及叶色变化与色素含量间的内在关联,可为红叶石楠造景应用和栽培管理提供理论依据.以红叶石楠‘红罗宾’品种2年生苗为试验材料,于2020年3月至11月在完全随机选取的3块面积大小相同、栽培管理基本一致的人工栽培小区中,采用随机取样和五点取样法共6次测定红罗宾石楠叶片的叶色参数值、色素含量、叶片相对含水量、干湿比和叶片pH值,并进行单因素方差分析和相关性分析.结果显示,在红罗宾石楠生长过程中,从3月至11月叶色由深红色渐变为深绿色,颜色指数趋于负值;花青素含量下降,与颜色指数的变化趋于一致,而类胡萝卜素与叶绿素含量均呈增加趋势;叶片含水量的变化趋势不明显;叶片细胞液pH在11月达最大值4.99;叶片颜色指数与花青素含量和相对含水量呈显著的正相关,而与叶绿素含量、类胡萝卜素含量以及pH值均呈显著的负相关,相对含水量与花青素含量呈显著的正相关,但是叶片细胞液的pH值与花青素含量和颜色指数均呈显著的负相关.本研究表明红罗宾石楠的红叶期为3-4月,夏季叶色完全转绿,叶色变绿主要跟叶片细胞液pH上升引起的花青素含量下降,而叶片发育引起的叶绿素和类和胡萝卜素含量上升有关.田间叶色观测结果与色差分析结果具有良好一致性,表明用颜色指数来对彩叶植物色彩进行量化是比较可靠的.(图6表1参42)

This study aimed to investigate the annual color change patterns of Photinia fraseri,specifically focusing on the relationship between leaf color change and pigment content,to provide a theoretical basis for the landscaping application and cultivation management of Photinia×fraseri.Three randomly selected artificial cultivation plots,each with the same area and similar cultivation management practices,were utilized in this study.Two-year-old seedlings of Photinia×fraseri‘Red Robin’served as the test material.From March to November 2020,leaf color parameters,pigment content,leaf relative water content,dry-wet ratio,and leaf pH value of‘Red Robin’were measured six times using random sampling and the five point sampling method.Subsequently,one-way ANOVA and correlation analysis were conducted.The results showed a gradual color change of the Photinia×fraseri‘Red Robin leaves from dark red to dark green during their growth process from March to November.The color index tended to be negative.The anthocyanin content decreased and exhibited consistency with the color index change,while the carotenoid and chlorophyll content showed an increasing trend.Leaf water content did not display a distinct pattern of change.The pH value of leaf cell sap reached its maximum of 4.99 in November.The leaf color index showed a significantly positive correlation with anthocyanin content and relative water content and a significantly negative correlation with chlorophyll and carotenoid content and pH value.Relative water content displayed a significant positive correlation with relative anthocyanin content,whereas the pH value of leaf cell sap exhibited a significant negative correlation with anthocyanin content and color index.Based on the study,the red leaf period of Photinia×fraseri‘Red Robin’was observed to be from March to April,with leaves completely transitioning to green during summer.The leaf color turning green was primarily associated with the decrease in anthocyanin content caused by the increase in pH value of leaf cell sap as well as the increase in chlorophyll and carotenoid content caused by leaf development.The study findings also highlight the reliability of the color index for quantifying the color of coleus plants,as there was good consistency between field observations of leaf color and the results of color difference analysis.