Plant Physiology, Pharmaceutical and Health Sciences Department, Faculty of Pharmacy, Universidad San Pablo-CEU Universities, Boadilla del Monte, Spain.
J Sci Food Agric. 2021 Jan 15;101(1):205-214. doi: 10.1002/jsfa.10632. Epub 2020 Aug 10.
The beneficial rhizobacterium, Pseudomonas fluorescens N 21.4, and its metabolic elicitors were inoculated in commercial cultivars of blackberry plants (Rubus cv. Loch Ness). Phenolic compounds present in red and black fruit and the expression of structural marker genes of the phenylpropanoid pathway during fruit ripening were studied.
An inverse relationship between gene expression and accumulation of metabolites was seen, except for the RuDFR gene, which had a direct correlation with cyanidin 3-O-glucoside synthesis, increasing its content 1.3 times when RuDFR was overexpressed in the red fruit of plants inoculated with the metabolic elicitors of P. fluorescens N 21.4, compared with red fruit of plants inoculated with N 21.4. The RuCHS gene also had a fundamental role in the accumulation of metabolites. Both rhizobacterium and metabolic elicitors triggered the flavonoid metabolism, enhancing the catechin and epicatechin content between 1.1 and 1.6 times in the case of red fruit and between 1.1 and 1.8 times in the case of black fruit. Both treatments also boosted the anthocyanin, quercetin, and kaempferol derivative content, highlighting the effects of metabolic elicitors in red fruit and the effects of live rhizobacterium in black fruit.
The metabolic elicitors' capacity to modulate gene expression and to increase secondary metabolites content was demonstrated. This work therefore suggests that they are effective, affordable, easily manageable, and ecofriendly plant inoculants that complement, or are alternatives to, beneficial rhizobacteria. © 2020 Society of Chemical Industry.
有益的根际细菌荧光假单胞菌 N 21.4 及其代谢诱导剂被接种到黑莓植物（Rubus cv. Loch Ness）的商业品种中。研究了红色和黑色水果中存在的酚类化合物以及苯丙烷途径结构标记基因在果实成熟过程中的表达。
基因表达与代谢物积累之间呈反比关系，但 RuDFR 基因除外，该基因与矢车菊素 3-O-葡萄糖苷的合成呈直接相关，当用荧光假单胞菌 N 21.4 的代谢诱导剂接种的植物的红色果实中 RuDFR 过表达时，与接种 N 21.4 的植物的红色果实相比，其含量增加了 1.3 倍。RuCHS 基因也在代谢物积累中起着重要作用。根际细菌和代谢诱导剂都触发了类黄酮代谢，使红色果实中的儿茶素和表儿茶素含量分别提高了 1.1-1.6 倍，黑色果实中的儿茶素和表儿茶素含量分别提高了 1.1-1.8 倍。两种处理方法还提高了花色苷、槲皮素和山奈酚衍生物的含量，突出了代谢诱导剂在红色果实中的作用和活根际细菌在黑色果实中的作用。
证明了代谢诱导剂调节基因表达和增加次生代谢物含量的能力。因此，本研究认为它们是有效、经济实惠、易于管理且环保的植物接种剂，可以补充有益根际细菌，或者替代有益根际细菌。© 2020 英国化学学会。
