Characterization of Plant Growth–Promoting Traits of Bacteria Isolated from Larval Guts of Diamondback Moth Plutella xylostella (Lepidoptera: Plutellidae)

Department of Agricultural Chemistry, College of Agriculture, Life and Environment Sciences, Chungbuk National University, Cheongju, 361763, Republic of Korea.
Current Microbiology (Impact Factor: 1.42). 05/2008; 56(4):327-33. DOI: 10.1007/s00284-007-9086-4
Source: PubMed


Eight bacterial isolates from the larval guts of Diamondback moths (Plutella xylostella) were tested for their plant growth-promoting (PGP) traits and effects on early plant growth. All of the strains tested positive for nitrogen fixation and indole 3-acetic acid (IAA) and salicylic acid production but negative for hydrogen cyanide and pectinase production. In addition, five of the isolates exhibited significant levels of tricalcium phosphate and zinc oxide solubilization; six isolates were able to oxidize sulfur in growth media; and four isolates tested positive for chitinase and beta-1,3-glucanase activities. Based on their IAA production, six strains including four that were 1-aminocyclopropane-1-carboxylate (ACC) deaminase positive and two that were ACC deaminase negative were tested for PGP activity on the early growth of canola and tomato seeds under gnotobiotic conditions. Acinetobacter sp. PSGB04 significantly increased root length (41%), seedling vigor, and dry biomass (30%) of the canola test plants, whereas Pseudomonas sp. PRGB06 inhibited the mycelial growth of Botrytis cinerea, Colletotrichum coccodes, C. gleospoiroides, Rhizoctonia solani, and Sclerotia sclerotiorum under in vitro conditions. A significant increase, greater than that of the control, was also noted for growth parameters of the tomato test plants when the seeds were treated with PRGB06. Therefore, the results of the present study suggest that bacteria associated with insect larval guts possess PGP traits and positively influence plant growth. Therefore, insect gut bacteria as effective PGP agents represent an unexplored niche and may broaden the spectrum of beneficial bacteria available for crop production.

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Available from: Rangasamy Anandham, Sep 02, 2015
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    • "Bacteria are reported to have the ability to produce low-molecular weight siderophores that are capable of sequestering Fe 3? and to help plants to have their iron requirement. Siderophores act as solubilizing agents of iron from minerals under conditions of iron limitation (Indiragandhi et al. 2008). Siderophores are reported to form stable complexes with heavy metals such as Al, Cd, Cu, Ga, In, Np, Pb, U and Zn and increase the soluble metal concentration (Rajkumar et al. 2010). "
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    ABSTRACT: The physiological and molecular responses of six strains of Streptomyces sp. (CAI-13, CAI-85, CAI-93, CAI-140, CAI-155 and KAI-180), with their proven potential for plant growth-promotion (PGP) in rice were studied to understand the mechanisms causing the beneficial effects. In this investigation, those six strains were evaluated for their PGP capabilities in chickpea in the 2012-13 and 2013-14 post-rainy seasons. All of the Streptomyces sp. strains exhibited enhanced nodule number, nodule weight, root weight and shoot weight at 30 days after sowing (DAS) and pod number, pod weight, leaf area, leaf weight and stem weight at 60 DAS in both seasons over the un-inoculated control. At chickpea crop maturity, the Streptomyces strains had enhanced stover yield, grain yield, total dry matter, pod weight, seed number and seed weight in both seasons over the un-inoculated control. In the rhizosphere, at crop maturity, the Streptomyces strains also significantly enhanced soil biological and mineral nutrient traits including microbial biomass carbon, dehydrogenase activity, total nitrogen, available phosphorous and organic carbon in both seasons over the un-inoculated control. Of the six strains of Streptomyces sp., CAI-85, CAI-93 and KAI-180 were found superior to CAI-155, CAI-140 and CAI-13, in terms of their effects on root and shoot development, nodule formation and crop productivity. Scanning electron microscopy micrographs had revealed the success in colonization of the chickpea roots by all six strains. This investigation further confirms the broad-spectrum of PGP activities by the selected Streptomyces sp.
    02/2015; 5(5). DOI:10.1007/s13205-015-0283-8
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    • "ACC deaminase, IAA, siderophore Poonguzhali et al. (2008) Serratia marcescens IAA, siderophore, HCN Selvakumar et al. (2008) Pseudomonas fluorescens ACC deaminase, phosphate solubilization Shaharoona et al. (2008) Acinetobacter sp., Pseudomonas sp. ACC deaminase, IAA, antifungal activity, N 2 -fixation, phosphate solubilization Indiragandhi et al. (2008) Enterobacter sp. ACC deaminase, IAA, siderophore, phosphate solubilization Kumar et al. (2008) Burkholderia ACC deaminase, IAA, siderophore, heavy metal solubilization, phosphate solubilization Jiang et al. (2008) Pseudomonas jessenii ACC deaminase, IAA, siderophore, heavy metal solubilization, phosphate solubilization Rajkumar and Freitas (2008) Pseudomonas aeruginosa ACC deaminase, IAA, siderophore, phosphate solubilization Ganesan (2008) ACC: 1-aminocyclopropane-1-carboxylate; EPS: exopolysaccharides; IAA: indole acetic acid. "
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    Arabian Journal of Chemistry 11/2014; 158. DOI:10.1016/j.arabjc.2014.11.020 · 3.73 Impact Factor
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    • "The precise source of IAA in ECB secretions is not known at this time. Auxin biosynthesis is common in microorganisms, and while not identified in insect secretions, bacteria isolated from the gut of the diamondback moth (Plutellaxylostella), were capable of producing IAA [75]. Recently, gall-inducing sawfly in the genus Pontania have been demonstrated to synthesize 20 ng IAA from 1 µg of isotopically labeled tryptophan; however, the source of this metabolic conversion remains unknown [76]. "
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    PLoS ONE 09/2013; 8(9):e73394. DOI:10.1371/journal.pone.0073394 · 3.23 Impact Factor
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