Objective The purpose of this investigation was to identify the polymorphisms of LCYE gene and the variation ofβ-carotene and carotenoids for understanding LCYE allele function in sweet corns and providing the reference and basis for biofortification breeding of pro-vitamin A.[Method] The contents ofβ-carotene and total carotenoid were measured by HPLC in 47 sweet corn inbred lines .The whole length of LCYE was amplified , cloned and sequenced .Association analysis was performed by combining the se-quences of LCYE gene with the content of β-carotene and total carotenoid .[Result and conclusion] The total of 75 polymorphism sites were detected in this study , which included 49 polymorphism sites located on the non-coding chromosome region and 26 polymorphism sites located on the exons of the LCYE gene. All these sites on the exons were SNPs and most of them were located on the fifth exon except for the forth and the ninth exon with a conserved sequence .All 13 detected INDELs located on the non-coding region . The fragment of these INDELs ranged from 1 to 40 bp and most of them were from 4 bp to 8 bp.Three polymorphic sites were detected to be associated with β-carotenoid and 6 polymorphic sites were detected to be associated with total carotenoid .Exon 1-2 and exon 5-6 were found to be significantly associated with these two phonotypes .The result identifies that LCYE gene is related to the biosynthetic pathway of the carotenoids and provides the theoretical basis for biofortificated breeding of pro -vitamin A in sweet corns .%【目的】鉴定甜玉米材料中LCYE基因的多态性和β-胡萝卜素和类胡萝卜素含量的变异，为了解甜玉米LCYE基因的等位基因功能及维生素A源强化育种提供参考和依据。【方法】以47份甜玉米自交系为材料，用高效液相色谱法检测β-胡萝卜素和总类胡萝卜素的含量，扩增LCYE基因并测序，结合LCYE基因的测序结果和β-胡萝卜素、总类胡萝卜素含量的表型值作关联分析。【结果和结论】在47份甜玉米自交系的LCYE基因的测序结果中共发现75个多态性位点，其中49个多态性位点分布在非编码区，26个多态性位点分布于LCYE基因的外显子区，且均为SNP，第5外显子区多态性位点最丰富，第4和第9外显子区未检测到多态性位点，其保守程度较高。关联分析检测到与β-胡萝卜素相关联的位点3个，与总类胡萝卜素含量关联的位点6个，位点exon1-2和exon5-6与2种表型极显著相关。本研究证明在甜玉米中LCYE基因与β-胡萝卜素和类胡萝卜素的合成显著相关，为甜玉米的维生素A源强化育种提供了理论基础。
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