摘要
为探究大红和无刺黄龙火龙果果实色泽差异的形成机理,以大红和无刺黄龙火龙果坐果后13、16、19、22、25、28 d共6个不同发育阶段果实为材料,测定不同部位(果肉、果皮、萼片)的色泽参数、甜菜色素总含量、组分和相对含量变化,并对结果进行相关性和主成分分析。结果表明:大红果肉a*值坐果后16 d逐渐增加呈现红色;果皮与萼片a*值坐果后19 d前为负值,19~28 d为正值且呈上升趋势,b*值坐果后22 d显著增加而后下降,表现为由绿色先转为红黄色而后转为红色。无刺黄龙果皮与萼片a*值在25 d前为负值,28 d绝对值趋近于0,b*值坐果后13~19 d呈平稳趋势,而后显著上升,表现为由绿色转为黄色。大红共检测到11种甜菜色素组分,以甜菜苷含量最高;总含量逐渐增加,28 d增加显著。无刺黄龙共检测到6种甜菜色素组分,以亮氨酸-甜菜黄素含量最高,果肉仅含甜菜苷配基和酪氨酸;果肉甜菜色素总含量差异不显著,果皮与萼片逐渐增加。2个品种间仅有甜菜苷配基1种共有组分。通过相关性分析可得,大红3个部位的a*值与甜菜色素总含量呈显著正相关,与甜菜苷的含量呈极显著性正相关。无刺黄龙果皮、萼片的b*值与甜菜色素总含量和亮氨酸-甜菜黄素的含量均呈显著正相关,果肉甜菜色素总含量与a*、b*、L*值的相关性均未达显著水平。对2个品种的甜菜色素组分进行主成分分析,大红提取了4个主成分,累积方差贡献率达79.23%;第1主成分甜菜红素类贡献率为34.30%,主要综合了甜菜苷、丙二酰甜菜苷等组分;第2主成分甜菜红素及代谢物综合类贡献率为21.35%,主要综合了2,17-Decarboxyphyllocactin、甜菜醛氨酸等。无刺黄龙提取了2个主成分,累计方差贡献率达84.21%;第1主成分甜菜黄素类贡献率为61.71%,主要综合了亮氨酸-甜菜黄素、酪氨酸-甜菜黄素等组分,这为火龙果色泽的评价和育种提供了新的思路。综上所述,大红火龙果和无刺黄龙果皮与萼片随着甜菜色素的增加逐渐转色;无刺黄龙果肉仅含甜菜色素代谢物,未发生转色;结合相关性和主成分分析,进一步推测,大红果实的红色主要由甜菜苷、丙二酰甜菜苷、2,17-Decarboxyphyllocactin贡献,无刺黄龙果皮与萼片的黄色主要由亮氨酸-甜菜黄素贡献,这为火龙果色泽的评价提供了新的思路。本研究阐述了火龙果果实色泽差异的形成机理,为探究火龙果果实的着色机制、色泽的评价及甜菜色素的开发利用奠定了理论基础。
In order to explore the formation mechanism of fruit color difference between Dahong and Wucihuanglong pitaya,the fruits at different development stages of 13 d,16 d,19 d,22 d,25 d and 28 d after fruit setting were sampled.The color parameters,total content,components and relative content change of Betalains in different parts(flesh,peel and sepal)were determined,and the results were analyzed by correlation and principal component analysis.Results showed that a*value of Dahong flesh gradually increased and the flesh showed red color 16 days after fruit setting.The a*value of the peel and sepal was negative before 19 d after fruit setting,positive during 19 d to 28 d and showed an upward trend;the b*value significantly increased and then decreased after 22 d after fruit setting,showing that green first turned to red and yellow,then turned to red.The a*value of the peel and sepal of Wucihuanglong was negative before 25 d,and the absolute value of 28 d was close to 0;the b*value showed a stable trend during 13 d to 19 d after fruit setting,and then increased significantly,showing that green turned to yellow.A total of 11 kinds of betalains were detected in Dahong,and the content of betanin was the highest.The total content increased gradually,and the increase was significant at 28 d.A total of 6 kinds of betalain components were detected in the Wucihuanglong,and leucine be-taxanthin content was the highest,while the flesh only contained betanidin and tyrosine.There was no significant dif-ference in the total content of betalains in flesh,but it increased gradually in peel and sepal.There was only one com-mon component of betanidin between the two varieties.According to the correlation analysis,the a*value of the three parts of Dahong was significantly positively correlated with the total content of betalains and extremely significantly positively correlated with the content of betanin.The b*values in the peel and sepal of Wucihuanglong were signifi-cantly positively correlated with the total content of betalain and the content of leucine betaxanthin,while the correla-tion between the total content of betalain in the flesh and the a*,b*and L*values was not significant.The principal component analysis of the betalains of the two varieties showed that Dahong extracted four principal components,and the cumulative variance contribution rate was 79.23%.The contribution rate of the first principal component was 34.30%,which mainly integrated the components of betanin and phyllocactin.The comprehensive contribution rate of the second principal component betaine and metabolites was 21.35%,mainly synthesizing 2,17-Decarboxyphyllocactin and betalamic acid.Two principal components were extracted from Wucihuanglong,and the accumulative rate reached 84.21%.The contribution rate of the first principal component betaxanthin was 61.71%,which mainly integrated leucine-betaxanthin,tyrosine-betaxanthin and other components,which provided a new idea for color evaluation and breeding of pitaya.In conclu-sion,the peel and sepal of Dahong and Wucihuanglong gradually changed color with the increase of betalains.The flesh of Wucihuanglong contained only metabolites of betalains,and did not change color.Combined with correlation and principal component analysis,it was further speculated that the red color of Dahong was mainly contributed by betanin,phyllocactin and 2,17-Decarboxyphyllocactin,and the yellow color of Wucihuanglong peel and sepal was mainly contributed by leu-cine-betaxanthin.This would provide a new idea for the evaluation of pitaya color.This study described the formation mecha-nism of color difference of pitaya,and would lay a theoretical foundation for exploring the color mechanism,color evaluation,as well as the development and utilization of betalains.
作者
胡莺菊
何云
李洪立
洪青梅
濮文辉
李琼
胡文斌
HU Yingju;HE Yun;LI Hongli;HONG Qingmei;PU Wenhui;LI Qiong;HU Wenbin(College of Horticulture,Hainan University,Haikou,Hainan 570228,China;Tropical Crop Genetic Resources Institute,ChineseAcademy of Tropical Agricultural Sciences,Haikou,Hainan 571101,China)
出处
《热带作物学报》
CSCD
北大核心
2024年第3期503-513,共11页
Chinese Journal of Tropical Crops
基金
海南省重大科技计划项目“热带果树种质资源精准评价与创新利用”(No.ZDKJ2021014)
国家科技资源共享服务平台:国家热带植物种质资源库(National Tropical Plants Germplasm Resource Center)。
关键词
火龙果
色泽
甜菜色素
组分
相关性分析
主成分分析
pitaya
color
betalains
components
correlation analysis
principal component analysis
