Pishchik Veronika N, Filippova Polina S, Mirskaya Galina V, Khomyakov Yuriy V, Vertebny Vitaliy E, Dubovitskaya Viktoriya I, Ostankova Yuliya V, Semenov Aleksandr V, Chakrabarty Debasis, Zuev Evgeny V, Chebotar Vladimir K
All-Russia Research Institute for Agricultural Microbiology, Podbelskogo hwy, 3, Pushkin, 196608 St. Petersburg, Russia.
Agrophysical Scientific Research Institute, Grazhdansky pr. 14, 195220 St. Petersburg, Russia.
Plants (Basel). 2021 Oct 29;10(11):2334. doi: 10.3390/plants10112334.
The present study demonstrates the Ni toxicity-ameliorating and growth-promoting abilities of two different bacterial isolates when applied to wheat ( L.) as the host plant. Two bacterial strains tolerant to Ni stress were isolated from wheat seeds and selected based on their ability to improve the germination of wheat plants; they were identified as AFI1 and AFI2. The protective effects of these epiphytic bacteria against Ni stress were studied in model experiments with two wheat cultivars: Ni stress-tolerant Leningradskaya 6 and susceptible Chinese spring. When these isolates were used as the inoculants applied to Ni-treated wheat plants, the growth parameters and the levels of photosynthetic pigments of the two wheat cultivars both under normal and Ni-stress conditions were increased, though AFI1 had a more pronounced ameliorative effect on the Ni contents in plant tissues due to its synthesis of siderophores. Over the 10 days of Ni exposure, the plant growth promotion bacteria (PGPB) significantly reduced the lipid peroxidation (LPO), ascorbate peroxidase (APX), superoxide dismutase (SOD) activities and proline content in the leaves of both wheat cultivars. The PGPB also increased peroxidase (POX) activity and the levels of chlorophyll , chlorophyll , and carotenoids in the wheat leaves. It was concluded that AFI1 is an ideal candidate for bioremediation and wheat growth promotion against Ni-induced oxidative stress, as it increases photosynthetic pigment contents, induces the antioxidant defense system, and lowers Ni metal uptake.
本研究表明，将两种不同的细菌分离株应用于作为寄主植物的小麦时，它们具有减轻镍毒性和促进生长的能力。从小麦种子中分离出两种耐镍胁迫的细菌菌株，并根据它们促进小麦植株发芽的能力进行筛选；它们被鉴定为AFI1和AFI2。在两个小麦品种的模型实验中研究了这些附生细菌对镍胁迫的保护作用：耐镍的列宁格勒6号和敏感的中国春小麦。当将这些分离株用作接种剂施用于经镍处理的小麦植株时，在正常和镍胁迫条件下，两个小麦品种的生长参数和光合色素水平均有所增加，尽管AFI1由于其铁载体的合成，对植物组织中的镍含量具有更明显的改善作用。在镍暴露的10天中，植物促生细菌（PGPB）显著降低了两个小麦品种叶片中的脂质过氧化（LPO）、抗坏血酸过氧化物酶（APX）、超氧化物歧化酶（SOD）活性和脯氨酸含量。PGPB还提高了小麦叶片中的过氧化物酶（POX）活性以及叶绿素a、叶绿素b和类胡萝卜素的水平。得出的结论是，AFI1是生物修复和促进小麦生长以抵抗镍诱导的氧化应激的理想候选者，因为它增加了光合色素含量，诱导了抗氧化防御系统，并降低了镍金属的吸收。
