沃柑树冠不同结果部位光照条件对果实品质的影响  

Effects of light conditions on fruit quality in different fruiting positions of Orah mandarin canopy

作　　者：贾聚金 陈香玲[2] 孙权 包心茹 张红艳[1] 徐娟[1] 柴利军[1] 邓秀新[1] 叶俊丽[1] JIA Jujin;CHEN Xiangling;SUN Quan;BAO Xinru;ZHANG Hongyan;XU Juan;CHAI Lijun;DENG Xiuxin;YE Junli(Key Laboratory of Horticultural Plant Biology,Ministry of Education/College of Horticulture and Forestry Sciences,Huazhong Agriculture University,Wuhan 430070,China;Institute of Horticulture,Guangxi Academy of Agricultural Sciences,Nanning 530007,China)

机构地区：[1]园艺植物生物学教育部重点实验室/华中农业大学园艺林学学院,武汉430070 [2]广西农业科学院园艺研究所,南宁530007

出　　处：《华中农业大学学报》2021年第6期112-118,共7页Journal of Huazhong Agricultural University

基　　金：国家重点研发计划项目(2018YFD1000203);国家自然科学基金项目(31930095)。

摘　　要：以沃柑树冠内膛遮阴果实和树冠外围光照充足果实为试材,对比分析了不同光照条件对果实外观色泽及内在品质的综合影响。结果显示:与光照充足的沃柑果实相比,遮阴的沃柑果实呈现更深的橙红色,其果皮中总类胡萝卜素含量提高了2.87倍,其中主要呈色色素β-柠乌素(红色)和9-顺式紫黄质(橙黄色)的含量分别增加了16.93倍和6.47倍;相关基因表达分析发现类胡萝卜素代谢途径主要结构基因均在遮阴果实中显著上调表达,其中β-柠乌素合成关键基因类胡萝卜素裂解双加氧酶(CCD4b)的表达量增加了11.78倍。结果表明,遮阴可以通过诱导沃柑果皮中类胡萝卜素合成相关基因的表达来促进果皮中类胡萝卜素的积累,最终使沃柑果皮呈现深橙红色;与光照充足的沃柑果实相比,遮阴果实的可溶性固形物、可滴定酸、可溶性糖以及有机酸含量、抗坏血酸含量均显著降低,表明光照条件影响了果实的内在品质。The shaded fruits in the inner canopy of Orah mandarin and the fruits with sufficient light at the periphery of the canopy were used to compare and analyze the comprehensive effects of light conditions on the appearance,color and internal quality of Orah mandarin.The results showed that the shaded fruits presented a deeper orange-red color compared with the fruits with sufficient light.The content of total carotenoid in the peel of the shaded fruits increased by 2.87 times,and the main color pigmentsβ-citraurin(red)and 9-cis violaxanthin(orange yellow)were increased by 16.93 times and 6.47 times,respectively.The results of gene expression analysis showed that the main structural genes of carotenoid metabolic pathway were significantly up-regulated in shaded fruits.The expression of carotenoid cleavage dioxygenase(CCD4b),a key gene forβ-citraurin biosynthesis,increased by 11.78 times.It is indicated that shading can promote carotenoid accumulation in the peel of Orah mandarin by inducing the expression of genes related to carotenoid biosynthesis,and ultimately make the peel dark orange-red.The content of soluble solids,titratable acid,soluble sugar,organic acid and ascorbic acid in shaded fruit was much lower than that in the fruit with sufficient light,indicating that light conditions affected the internal quality of the fruit.It will provide a theoretical basis for further elucidating the underlying mechanisms of how light regulate fruit quality,and ultimately improving the fruit quality of citrus by breeding and cultivation.

关 键 词：光照 遮阴 沃柑 果实品质 类胡萝卜素 

分 类 号：S666.901[农业科学—果树学]