多氯联苯促进毛白杨不定根分化的效应  

Polychlorinated Biphenyls Promotes Differentiation on Adventitious Roots of Populous tomentosa

作　　者：刘铭[1,2] 刘霞 孙然[1,2] 李玉灵 杜克久[1,2] Ming Liu;Xia Liu;Ran Sun;Yuling Li;Kejiu Du(Agricultural University of Hebei,Baoding 071000,China;Key Laboratory of Tree Species Germplasm Resource and Forest Protection of Hebei Province,Baoding 071000,China)

机构地区：[1]河北农业大学,保定071000 [2]河北省林木种子资源与森林保护重点实验室,保定071000

出　　处：《植物学报》2018年第6期764-772,共9页Chinese Bulletin of Botany

基　　金：河北省自然科学基金(No.C2018204134);国家自然科学基金(No.30972384);“十二五”农村领域国家科技计划(No.2012 AA101403);环境化学与生态毒理学国家重点实验室开放基金(No.KF2009-03)

摘　　要：多氯联苯是一种典型的持久性有机污染物。研究表明多氯联苯具有毒物兴奋效应,但其影响植物生长发育的机制尚不清楚。以毛白杨(Populous tomentosa)组培苗为材料,探讨3mg·L^-1Aroclor1254对不定根分化、植物激素水平、与生长素相关的P009g125900、P006g142600和P002g2227003因表达、与细胞分裂素相关的P005g2489和P005g2376基因表达的影响。结果显示,Aroclor1254可促进毛白杨组培苗不定根分化,缩短不定根初根时间与分化率达100%的时间,提高不定根数目:在不定根诱导期,用Aroclor1254单独诱导,IAA/(ZR+dhZR)比值与阳性对照无显著差异,P006g142600、P002g222700、P009g125900、P005g2489和P005g2376基因表达变化趋势与IBA单独诱导下各基因表达变化趋势一致。为验证Aroclor1254是否具有生长素效应,以玉米(Zea mays)和转生长素报告基因DR5::GUS的拟南芥(Arabidopsis thaliana)为材料,观察Aroclor1254对胚芽鞘生长及DR5::GUS基因表达的影响。结果显示,一定浓度的Aroclor1254对胚芽鞘的生长无显著影响,但可诱导生长素报告基因表达。以上结果表明,多氯联苯类化合物Aroclor1254虽不属于植物生长调节剂,但具有毒物兴奋效应,在一定浓度下具有类似生长素的生物学活性。Polychlorinated biphenyls(PCBs) pose serious harm to humans and the environment. PCBs have a hormesis effect, but the inner mechanism still remains unknown. In this paper, we used Populous tomentosa seedlings to investigate the effect of treatment with a PCB compound, Aroclor1254(3 mg·L–1), on the differentiation of adventitious roots, phytohormone content and the expression of P009 g125900, P006 g142600, and P002 g222700 genes related to auxin expression as well as P005 g2489 and P005 g2376 genes related to cytokinin expression. Aroclor1254 could promote the differentiation of adventitious roots, shorten the initial root formation time of adventitious roots, and enhance the adventitious root number. During adventitious root differentiation, Aroclor1254 treatment alone had a similar effect as IBA alone on IAA/(ZR+dhZR) content and the gene expression of P006 g142600, P002 g222700, P009 g125900, P005 g2489, and P005 g2376. To further verify the auxin effect of Aroclor1254, we used Zea mays and transgenic Arabidopsis thaliana modified with a DR5::GUS auxin reporter gene to investigate the growth of coleoptiles or the response pattern of DR5::GUS to Aroclor1254 exposure. Aroclor1254 at a suitable concentration range could induce DR5::GUS gene expression but had no effect on the growth of coleoptiles. Thus, Aroclor1254 has a biological effect of auxin and can positively affect the differentiation of adventitious roots of P. tomentosa seedlings; a phenomenon called hormesis, but is not a plant growth regulator.

关 键 词：Aroclor1254 不定根分化 植物激素 基因表达 胚芽鞘 DR5::GUS 

分 类 号：S792.117[农业科学—林木遗传育种]