ACC-deaminase producing plant growth promoting rhizobacteria and biochar mitigate adverse effects of drought stress on maize growth

PLoS One. 2020 Apr 6;15(4):e0230615. doi: 10.1371/journal.pone.0230615. eCollection 2020.

Abstract

Availability of good quality irrigation water is a big challenge in arid and semi arid regions of the world. Drought stress results in poor plant growth and low yield; however, the rhizobacteria, capable of producing 1-aminocyclopropane-1-carboxylate (ACC)-deaminase are likely to improve crop growth and productivity under drought stress. Similarly, biochar could also ameliorate the negative impacts of drought stress. Therefore, this pot experiment was conducted to evaluate the role of ACC-deaminase producing plant growth promoting rhizobacteria (PGPR) alone and in combinations with timber-waste biochar in improving maize growth under drought stress. The ACC-deaminase producing rhizobacteria, Pseudomonas aeruginosa, Enterobacter cloacae, Achromobacter xylosoxidans and Leclercia adecarboxylata were studied along with two rates (0.75 and 1.50% of the soil weight) of biochar under three moisture levels i.e., normal moisture, mild drought stress and severe drought stress. The E. cloacae in conjunction with higher rate of biochar produced a significant improvement i.e., up to 60, 73, 43, 69, 76 and 42% respectively, in grain yield plant-1, photosynthetic rate, stomatal conductance, chlorophyll a, total chlorophyll and carotenoids contents of maize as compared to the control under mild drought stress. Similarly, A. xylosoxidans with higher rate of biochar also enhanced grain yield plant-1, photosynthetic rate, stomatal conductance, chlorophyll a, total chlorophyll and carotenoids contents of maize up to 200, 213, 113, 152, 148 and 284%, respectively over control under severe drought stress. In conclusion, combination of ACC-deaminase containing PGPR, A. xylosoxidans and biochar (0.75%) proved an effective technique to improve maize growth and productivity under drought stress.

Publication types

  • Research Support, Non-U.S. Gov't
  • Retracted Publication

MeSH terms

  • Bacteria / enzymology*
  • Bacteria / metabolism
  • Bacterial Physiological Phenomena
  • Carbon-Carbon Lyases / biosynthesis*
  • Carotenoids / metabolism
  • Charcoal / pharmacology*
  • Chlorophyll / metabolism
  • Droughts*
  • Plant Shoots / growth & development
  • Proline / metabolism
  • Rhizosphere*
  • Stress, Physiological
  • Zea mays / drug effects*
  • Zea mays / growth & development
  • Zea mays / microbiology*
  • Zea mays / physiology

Substances

  • biochar
  • Chlorophyll
  • Charcoal
  • Carotenoids
  • Proline
  • 1-aminocyclopropane-1-carboxylate deaminase
  • Carbon-Carbon Lyases

Grants and funding

SD is grateful to the Higher Education Commission [HEC] of Pakistan to provide Indigenous Scholarship (PIN: 315-8403-2AV3-049) for his Ph.D. study. This paper is part of SD's doctoral thesis. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. There was no additional external funding received for this study.