基于SSR标记的4种榧树属植物遗传多样性及遗传结构研究

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中图分类号：S791.53 文献标识号：A 文章编号：1001-4942（2026）01-0036-11

AbstractTo unveil the genetic diversity and structure of Toreya plants and lay a theoretical foundation for evaluating，protecting and utilizing germplasm resources，a total of 295 samples from 4 Torreya species were used as materials.After selection，15 pairs of selected primers were employed for SSR-PCR amplification across all samples，and the amplification products were analyzed by capillry electrophores detection to explore their genetic diversity and structure，and cluster analysis was conducted. The results revealed the folowing insights：（1） Based on the effective alele，the genetic diversity from high to low was Torreya fargesii （ P= （204号 87.50% ， He=0.396 ， I=0.740 ），Torreya taxifolia （ P=86.67% ， He=0.342 ， I=0.596 ），Torreya parvifolia （ P=73.33% ， He=0.285 ， I=0.480 ），and Torreya yunnanensis （ P=57.57% ， He=0.194 ， I=0.332 ）. （2） The average Fis value of 21 Torreya populations was O.174， the average Fst value was 0.490，and the Nm was 0.260， indicating that gene exchange occurred infrequently. The Fit value of Torreya populations was greater than the Fis value，suggesting that the heterozygous level between populations was higher than that within populations.（3）The results ofthe analysis of molecular variance indicated that the genetic variation of Torreya plants mainly originated among populations with a variable coefficient of 58% . The Nei's standard genetic distance among 21 populations ranged from 0.018 to 2.453 with an average of 0.609. Overall，the genetic distance was positively correlated with the geographical distance （ r=0.759 ， P<0.05 ），while there was no significant correlation between the genetic distance and geographical distance in T. yunnanensis and T. fargesii. （4） Genetic similarity coeffcients among the21 populations were ranged from 0.403 to O.983.Using a threshold of 0.12，the populations were grouped into 2 major categories with T. taxifolia forming one category and the remaining 2O populations of the other three species another.At a threshold of O.58，they could be divided into 4 major categories.

KeywordsTorreya; SSR marker; Genetic diversity;Genetic structure

榧树属（Torreya）也称榧属，隶属红豆杉科（Taxaceae），为古老珍稀的子遗植物，该属共包括10 种植物（含2个变种），均分布于北半球，其中北美产2种［佛罗里达榧（Torreyataxifolia）和加州榧（Torreyacalifornica）]，日本产1种[日本榧（Torreyanucifera）]，其余7种在我国均有自然分布，分别为榧树（Torreya grandis）、巴山榧（Torreyafargesii）长叶榧（Torreya jackii）云南榧（Torreyayunnanensis）、四川榧（Torreya parvifolia）、九龙山榧（Torreya grandis var. jiulongshanensis ）、大盘山榧（Torreya dapanshanica）[1-6]。（剩余12544字）