Studies have indicated that graphene oxide (GO) could regulated Brassica napus L. root growth via abscisic acid (ABA) and indole-3-acetic acid (IAA). To study the mechanism and interaction between GO and IAA further, B. napus L (Zhongshuang No. 9) seedlings were treated with GO and IAA accordance with a two factor completely randomized design. GO and IAA cotreatment significantly regulated the root length, number of adventitious roots, and contents of IAA, cytokinin (CTK) and ABA. Treatment with 25 mg/L GO alone or IAA (> 0.5 mg/L) inhibited root development. IAA cotreatment enhanced the inhibitory role of GO, and the inhibition was strengthened with increased in IAA concentration. GO treatments caused oxidative stress in the plants. The ABA and CTK contents decreased; however, the IAA and gibberellin (GA) contents first increased but then decreased with increasing IAA concentration when IAA was combined with GO compared with GO alone. The 9-cis-epoxycarotenoid dioxygenase (NCED) transcript level strongly increased when the plants were treated with GO. However, the NCED transcript level and ABA concentration gradually decreased with increasing IAA concentration under GO and IAA cotreatment. GO treatments decreased the transcript abundance of steroid 5-alpha-reductase (DET2) and isochorismate synthase 1 (ICS), which are associated with brassinolide (BR) and salicylic acid (SA) biosynthesis, but increased the transcript abundance of brassinosteroid insensitive 1-associated receptor kinase 1 (BAK1), cam-binding protein 60-like G (CBP60) and calmodulin binding protein-like protein 1, which are associated with BR and SA biosynthesis. Last, GO treatment increased the transcript abundance of 1-aminocyclopropane-1-carboxylic acid synthase 2 (ACS2), which is associated with the ethylene (ETH) pathway. Treatment with 25 mg/L GO or IAA (> 0.5 mg/L) inhibited root development. However, IAA and GO cotreatment enhanced the inhibitory role of GO, and this inhibition was strengthened with increased IAA concentration. IAA is a key factor in the response of B. napus L to GO and the responses of B. napus to GO and IAA cotreatment involved in multiple pathways, including those involving ABA, IAA, GA, CTK, BR, SA. Specifically, GO and IAA cotreatment affected the GA content in the modulation of B. napus root growth.

中文翻译：

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氧化石墨烯和吲哚-3-乙酸共同处理通过多种植物激素途径调节甘蓝型油菜的根生长

研究表明，氧化石墨烯（GO）可以通过脱落酸（ABA）和吲哚-3-乙酸（IAA）调节甘蓝型油菜的根生长。为了进一步研究GO与IAA的作用机理和相互作用，按照两因素完全随机设计，对GO.IAP（中双9号）幼苗进行了GO和IAA处理。GO和IAA共同处理可显着调节根长，不定根数以及IAA，细胞分裂素（CTK）和ABA的含量。单独用25 mg / L GO或IAA（> 0.5 mg / L）处理可抑制根发育。IAA共处理增强了GO的抑制作用，并且随着IAA浓度的增加，抑制作用增强。GO处理引起植物的氧化应激。ABA和CTK含量下降；然而，与单独使用GO相比，IAA与GO结合使用时，IAA和赤霉素（GA）含量先增加，然后随着IAA浓度的增加而降低。当用GO处理植物时，9-顺式-环氧类胡萝卜素双加氧酶（NCED）的转录水平大大增加。然而，在GO和IAA共处理下，随着IAA浓度的增加，NCED的转录水平和ABA浓度逐渐降低。GO处理降低了与油菜素内酯（BR）和水杨酸（SA）生物合成相关的类固醇5-α-还原酶（DET2）和等油酸合酶1（ICS）的转录本丰度，但增加了对油菜素类固醇不敏感的1-的转录本丰度相关受体激酶1（BAK1），凸轮结合蛋白60-样G（CBP60）和钙调蛋白结合蛋白-样蛋白1，与BR和SA的生物合成有关。最后，GO处理增加了1-氨基环丙烷-1-羧酸合酶2（ACS2）的转录丰度，这与乙烯（ETH）途径有关。用25 mg / L GO或IAA（> 0.5 mg / L）处理可抑制根发育。但是，IAA和GO协同处理增强了GO的抑制作用，并且随着IAA浓度的增加，这种抑制作用得到了加强。IAA是甘蓝型油菜L对GO的反应以及甘蓝型油菜对GO和IAA共同处理的反应的关键因素，涉及多种途径，包括涉及ABA，IAA，GA，CTK，BR，SA的途径。具体而言，GO和IAA共同处理影响了甘蓝型油菜根生长中的GA含量。与乙烯（ETH）途径相关。用25 mg / L GO或IAA（> 0.5 mg / L）处理可抑制根发育。但是，IAA和GO协同处理增强了GO的抑制作用，并且随着IAA浓度的增加，这种抑制作用得到了加强。IAA是甘蓝型油菜L对GO的反应以及甘蓝型油菜对GO和IAA共同处理的反应的关键因素，涉及多种途径，包括涉及ABA，IAA，GA，CTK，BR，SA的途径。具体而言，GO和IAA共同处理影响了甘蓝型油菜根生长中的GA含量。与乙烯（ETH）途径相关。用25 mg / L GO或IAA（> 0.5 mg / L）处理可抑制根发育。但是，IAA和GO协同处理增强了GO的抑制作用，并且随着IAA浓度的增加，这种抑制作用得到了加强。IAA是甘蓝型油菜L对GO的反应以及甘蓝型油菜对GO和IAA共同处理的反应的关键因素，涉及多种途径，包括涉及ABA，IAA，GA，CTK，BR，SA的途径。具体而言，GO和IAA共同处理影响了甘蓝型油菜根生长中的GA含量。IAA是甘蓝型油菜L对GO的反应以及甘蓝型油菜对GO和IAA共同处理的反应的关键因素，涉及多种途径，包括涉及ABA，IAA，GA，CTK，BR，SA的途径。具体而言，GO和IAA共同处理影响了甘蓝型油菜根生长中的GA含量。IAA是甘蓝型油菜L对GO的反应以及甘蓝型油菜对GO和IAA共同处理的反应的关键因素，涉及多种途径，包括涉及ABA，IAA，GA，CTK，BR，SA的途径。具体而言，GO和IAA共同处理影响了甘蓝型油菜根生长中的GA含量。