Effect of flax rhizobacteria on germination and seedling growth under copper toxicity

Year 2025, Volume: 9 Issue: 2, 477 - 492, 26.06.2025

Murat Güler , Sancar Fatıh Ozcan , Burak Önol

https://doi.org/10.31015/2025.2.21

Abstract

Plant growth promoting rhizobacteria (PGPR) supports plant growth by decreasing heavy metal levels in soil through methods that alter metal pathways and convert toxins into safe forms. Five rhizobacterial isolates (FLX-1, FLX-2, FLX-3, FLX-4, and FLX-5) isolated from flax rhizosphere were identified using MALDI-TOF-MS techniques based on morphology, biochemistry, and plant growth-promoting properties. Four isolates (FLX-1, FLX-2, FLX-3, FLX-5) capable of fixing nitrogen, four (FLX-1, FLX-3, FLX-4, FLX-5) dissolving inorganic phosphate, and three (FLX-2, FLX-4, FLX-5) producing IAA and HCN. Additionally, in this study, the effects of 5 different rhizobacteria and copper (CuSO4) doses (0, 5, 10, 15, and 20 mM) on growth and development parameters of flax seeds were determined under fully controlled climate chambers. Moreover, Different rhizobacteria treatments significantly improved growth and development parameters in flax seed compared to the control group. It was observed that increasing copper doses resulted in a significant decrease in parameters such as germination rate, mean germination time, germination power index, root length, and shoot length in bacterial treatments. When evaluating the responses of different rhizobacteria treatments to copper heavy metal in flax seed germination, it was determined that the treatment of Pseudomonas chlororaphis FLX-5 yielded better results compared to other treatments and was effective in reducing the negative effects of copper in terms of the tested germination characteristics. In conclusion, the current study suggests that Pseudomonas chlororaphis FLX-5 may efficiently be used in tolerating copper toxicity, indicating that further research is needed in this area.

Keywords

Flax , Copper , PGPR , Germination , Pseudomonas chlororaphis

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