A newly discovered ageing-repair bacterium,Pseudomonas geniculata, isolated from rescuegrass (Bromus cartharticusVahl) promotes the germination and seedling growth of aged seeds

Abstract

Plant-growth-promoting rhizobacteria (PGPR) have been shown to relieve various biotic and abiotic stresses, but little information is available regarding their influence on germination and seedling growth of aged seeds. We isolated a promising PGPR from rescuegrass (Bromus cartharticus Vahl) roots and investigated the effect of PGPR biopriming combined with another seed priming treatment on aged rescuegrass seeds using an orthogonal matrix design with four factors. A potential ageing-repair bacterium, BCR5 (Pseudomonas geniculata), was selected from the screening trials and was identified. The reintroduction of strain BCR5 into the aged seeds pre-primed with different approaches had positive effects on germination and seedling growth. The results indicated that the bacterial cell density was the most effective factor for seed germination and vigour. Four factors were optimized for this study, including an artificial ageing duration of 54.21 h, bacterial cell density of 527.50 × 106 CFU·mL−1, and priming with H2O2 for 14.50 h, after analyzing the range and variance, and using binary quadratic regressions. Furthermore, the treatment also affected the content of malondialdehyde and the activities of superoxide dismutase and peroxidase. Bio-priming of the PGPR with another seed priming approach could be exploited as a promising technique for reinvigorating aged seeds. Moreover, we unexpectedly found that an appropriate artificial ageing treatment could break seed dormancy.

Assessing hydrolytic enzyme production ability of bacterial strains from bovine manure as potential biowaste conversion candidates

“…Strains of Pseudomonas showed a different level of amylase, cellulase activity as observed in; Pseudomonas geniculata and Pseudomonas hibiscicola and had been reported in the literature [32]. Chitinase and protease activity by both strains were reported but analyzed only qualitatively.…”

A Newly Discovered Humic-Reducing Bacterium, Pseudomonas geniculata PQ01, Isolated From Paddy Soil Promotes Paraquat Anaerobic Transformation

“…P. geniculata has much more potential applications in the field of environment protection. As a strain of environmental origin, P. geniculata has been reported capable of degrading phenanthrene, T-2 toxin, nicotine, and industrial dyes ( Shi et al, 2013 ; Yang et al, 2013 ; Liu et al, 2014 ), and also active in nitrogen fixation, plant-growth promotion, and seedling growth of aged seeds ( Zhang et al, 2010 ; Gopalakrishnan et al, 2015 ; Liu et al, 2019 ). In this study, we identify a new anaerobic metabolism of P. geniculata PQ01 that can effectively reduce soluble humics analogs and insoluble Fe(III) (hydr)oxides under anaerobic conditions, using glucose, sucrose, acetic acid, formic acid, or pyruvic acid as the electron donor.…”