Interactive effect of 24-epibrassinolide and plant growth promoting rhizobacteria inoculation restores photosynthetic attributes in Brassica juncea L. under chlorpyrifos toxicity. (1st March 2023)

• Record Type: Journal Article
• Authors: Bakshi, Palak; Sharma, Pooja; Chouhan, Rekha; Mir, Bilal Ahmad; Gandhi, Sumit G.; Bhardwaj, Renu; Alam, Pravej; Ahmad, Parvaiz
• Is Part Of: Environmental pollution. Volume 320(2023)
• Publication Date: 2023-03-01
• Subjects: Brassica juncea -- Chlorpyrifos -- Plant growth promoting rhizobacteria -- 24-epibrassinolide -- Photosynthesis -- Photosystem II -- Gene expression; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2022.120760
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Chlorpyrifos (CP) is a commonly used organophosphorous pesticide that is frequently utilised in the agricultural industry because of its great efficiency and inexpensive cost. The focus of the present study was to assess the impact of CP toxicity on Brassica juncea L. and to unravel the ameliorative potential of phytohormone, 24-epibrassinolide (EBL) mediated plant-microbe ( Pseudomonas aeruginosa (B1), Burkholderia gladioli (B2)) interaction in B. juncea L. The maximum significant increment in the total chlorophyll, carotenoids, xanthophyll, anthocyanin and flavonoid content with EBL and B2 treatment in CP stressed B. juncea seedlings on spectrophotometric analysis were observed. Autofluorescence imaging of photosynthetic pigments i.e. chlorophyll, carotenoids, and total phenols with confocal microscopy showed maximum fluorescence with EBL and B2. Furthermore, when compared to CP stressed seedlings, scanning electron microscopy (SEM) study of the abaxial surface of leaves revealed a recovery in stomatal opening. The supplementation of EBL and PGPR (plant growth promoting rhizobacteria) improved the level of psb A (D1 subunit PSII) and psb B (CP 47 subunit of PSII) genes expression. The expression analysis of chalcone synthase (CHS), Phenylalanine ammonialyase (PAL), Phyotene synthase (PSY) with RT-PCR system showed up-regulation in the expression when supplemented with EBL and PGPR. As a result, the current study suggests that EBL and PGPR together, can reduce CP-induced toxicity in B. juncea seedlings and recovering the seedling biomass. Graphical abstract: Image 1 Highlights: Chlorpyrifos (CP) toxicity reduced growth, biomass and photosynthetic activity in mustard. Seed priming with 24-epibrassinolide (EBL) reversed the negative effect of CP stress. Exogenous application of PGPR modulated the growth in mustard plants under CP stress. EBL and PGPR supplementation regulate the key genes of photosystem II psbA and psb B. EBL and PGPR upregulates CHS, PSY and PAL gene expression.