Limits...
Cultivation-Based and Molecular Assessment of Bacterial Diversity in the Rhizosheath of Wheat under Different Crop Rotations.

Tahir M, Mirza MS, Hameed S, Dimitrov MR, Smidt H - PLoS ONE (2015)

Bottom Line: T-34 to wheat plants increased root length, root and shoot dry weight and dry weight of rhizosheathsoil when compared to non-inoculated control plants, and under both crop rotations.Diversity of rhizosheath-associated bacteria was evaluated by cultivation, as well as by 454-pyrosequencing of PCR-tagged 16S rRNA gene amplicons.From a total of 46,971 sequences, 10.9% showed ≥97% similarity with 16S rRNA genes of 32 genera previously shown to include isolates with plant growth promoting activity (nitrogen fixation, phosphate-solubilization, IAA production).

View Article: PubMed Central - PubMed

Affiliation: National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road Faisalabad, Punjab, Pakistan.

ABSTRACT
A field study was conducted to compare the formationand bacterial communities of rhizosheaths of wheat grown under wheat-cotton and wheat-rice rotation and to study the effects of bacterial inoculation on plant growth. Inoculation of Azospirillum sp. WS-1 and Bacillus sp. T-34 to wheat plants increased root length, root and shoot dry weight and dry weight of rhizosheathsoil when compared to non-inoculated control plants, and under both crop rotations. Comparing both crop rotations, root length, root and shoot dry weight and dry weight of soil attached with roots were higher under wheat-cotton rotation. Organic acids (citric acid, malic acid, acetic acid and oxalic acid) were detected in rhizosheaths from both rotations, with malic acid being most abundant with 24.8±2 and 21.3±1.5 μg g(-1) dry soil in wheat-cotton and wheat-rice rotation, respectively. Two sugars (sucrose, glucose) were detected in wheat rhizosheath under both rotations, with highest concentrations of sucrose (4.08±0.5 μg g(-1) and 7.36±1.0 μg g(-1)) and glucose (3.12±0.5 μg g(-1) and 3.01± μg g(-1)) being detected in rhizosheaths of non-inoculated control plants under both rotations. Diversity of rhizosheath-associated bacteria was evaluated by cultivation, as well as by 454-pyrosequencing of PCR-tagged 16S rRNA gene amplicons. A total of 14 and 12 bacterial isolates predominantly belonging to the genera Arthrobacter, Azospirillum, Bacillus, Enterobacter and Pseudomonaswere obtained from the rhizosheath of wheat grown under wheat-cotton and wheat-rice rotation, respectively. Analysis of pyrosequencing data revealed Proteobacteria, Bacteriodetes and Verrucomicrobia as the most abundant phyla in wheat-rice rotation, whereas Actinobacteria, Firmicutes, Chloroflexi, Acidobacteria, Planctomycetes and Cyanobacteria were predominant in wheat-cotton rotation. From a total of 46,971 sequences, 10.9% showed ≥97% similarity with 16S rRNA genes of 32 genera previously shown to include isolates with plant growth promoting activity (nitrogen fixation, phosphate-solubilization, IAA production). Among these, the most predominant genera were Arthrobacter, Azoarcus, Azospirillum, Bacillus, Cyanobacterium, Paenibacillus, Pseudomonas and Rhizobium.

No MeSH data available.


Related in: MedlinePlus

Detection of sugars (μg.g-1 dry soil) in rhizosheaths of wheat.Plants were inoculated with Azospirillum sp. WS-1, Bacillus sp. T-34 or non-inoculated (control). Sugars were collected by washing the roots containing soil as rhizosheath in 30 mL sterilized distilled water for 5–10 minutes. The values given are an average of 3 replicates. Letters Aa, Bb and Cc represents the significance level by comparison of means.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4487687&req=5

pone.0130030.g003: Detection of sugars (μg.g-1 dry soil) in rhizosheaths of wheat.Plants were inoculated with Azospirillum sp. WS-1, Bacillus sp. T-34 or non-inoculated (control). Sugars were collected by washing the roots containing soil as rhizosheath in 30 mL sterilized distilled water for 5–10 minutes. The values given are an average of 3 replicates. Letters Aa, Bb and Cc represents the significance level by comparison of means.

Mentions: In the present study two sugars were detected in the rhizosheath of wheat grown under either crop system. Under wheat-rice rotation sucrose concentration was 2.35±0.41 μg.g-1 dry soil, whereas glucose was 2.63±0.3 μg.g-1 dry soil (Fig 3). Higher amounts were detected under wheat-cotton rotation, where sucrose concentration was 3.55±0.5 μg.g-1 of dry soil and glucose was 2.69±0.3 μg.g-1 of dry soil (Fig 3). However, comparing treatments, higher (P<0.05) sucrose (4.08±0.5 μg.g-1 and 7.36±1.0 μg.g-1, wheat-rice and wheat-cotton, respectively) and glucose concentrations (3.12±0.5 μg.g-1 and 3.01± μg.g-1, wheat-rice and wheat-cotton, respectively) were detected in the rhizosheath of non-inoculated control plants (Fig 3).


Cultivation-Based and Molecular Assessment of Bacterial Diversity in the Rhizosheath of Wheat under Different Crop Rotations.

Tahir M, Mirza MS, Hameed S, Dimitrov MR, Smidt H - PLoS ONE (2015)

Detection of sugars (μg.g-1 dry soil) in rhizosheaths of wheat.Plants were inoculated with Azospirillum sp. WS-1, Bacillus sp. T-34 or non-inoculated (control). Sugars were collected by washing the roots containing soil as rhizosheath in 30 mL sterilized distilled water for 5–10 minutes. The values given are an average of 3 replicates. Letters Aa, Bb and Cc represents the significance level by comparison of means.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4487687&req=5

pone.0130030.g003: Detection of sugars (μg.g-1 dry soil) in rhizosheaths of wheat.Plants were inoculated with Azospirillum sp. WS-1, Bacillus sp. T-34 or non-inoculated (control). Sugars were collected by washing the roots containing soil as rhizosheath in 30 mL sterilized distilled water for 5–10 minutes. The values given are an average of 3 replicates. Letters Aa, Bb and Cc represents the significance level by comparison of means.
Mentions: In the present study two sugars were detected in the rhizosheath of wheat grown under either crop system. Under wheat-rice rotation sucrose concentration was 2.35±0.41 μg.g-1 dry soil, whereas glucose was 2.63±0.3 μg.g-1 dry soil (Fig 3). Higher amounts were detected under wheat-cotton rotation, where sucrose concentration was 3.55±0.5 μg.g-1 of dry soil and glucose was 2.69±0.3 μg.g-1 of dry soil (Fig 3). However, comparing treatments, higher (P<0.05) sucrose (4.08±0.5 μg.g-1 and 7.36±1.0 μg.g-1, wheat-rice and wheat-cotton, respectively) and glucose concentrations (3.12±0.5 μg.g-1 and 3.01± μg.g-1, wheat-rice and wheat-cotton, respectively) were detected in the rhizosheath of non-inoculated control plants (Fig 3).

Bottom Line: T-34 to wheat plants increased root length, root and shoot dry weight and dry weight of rhizosheathsoil when compared to non-inoculated control plants, and under both crop rotations.Diversity of rhizosheath-associated bacteria was evaluated by cultivation, as well as by 454-pyrosequencing of PCR-tagged 16S rRNA gene amplicons.From a total of 46,971 sequences, 10.9% showed ≥97% similarity with 16S rRNA genes of 32 genera previously shown to include isolates with plant growth promoting activity (nitrogen fixation, phosphate-solubilization, IAA production).

View Article: PubMed Central - PubMed

Affiliation: National Institute for Biotechnology and Genetic Engineering (NIBGE), Jhang Road Faisalabad, Punjab, Pakistan.

ABSTRACT
A field study was conducted to compare the formationand bacterial communities of rhizosheaths of wheat grown under wheat-cotton and wheat-rice rotation and to study the effects of bacterial inoculation on plant growth. Inoculation of Azospirillum sp. WS-1 and Bacillus sp. T-34 to wheat plants increased root length, root and shoot dry weight and dry weight of rhizosheathsoil when compared to non-inoculated control plants, and under both crop rotations. Comparing both crop rotations, root length, root and shoot dry weight and dry weight of soil attached with roots were higher under wheat-cotton rotation. Organic acids (citric acid, malic acid, acetic acid and oxalic acid) were detected in rhizosheaths from both rotations, with malic acid being most abundant with 24.8±2 and 21.3±1.5 μg g(-1) dry soil in wheat-cotton and wheat-rice rotation, respectively. Two sugars (sucrose, glucose) were detected in wheat rhizosheath under both rotations, with highest concentrations of sucrose (4.08±0.5 μg g(-1) and 7.36±1.0 μg g(-1)) and glucose (3.12±0.5 μg g(-1) and 3.01± μg g(-1)) being detected in rhizosheaths of non-inoculated control plants under both rotations. Diversity of rhizosheath-associated bacteria was evaluated by cultivation, as well as by 454-pyrosequencing of PCR-tagged 16S rRNA gene amplicons. A total of 14 and 12 bacterial isolates predominantly belonging to the genera Arthrobacter, Azospirillum, Bacillus, Enterobacter and Pseudomonaswere obtained from the rhizosheath of wheat grown under wheat-cotton and wheat-rice rotation, respectively. Analysis of pyrosequencing data revealed Proteobacteria, Bacteriodetes and Verrucomicrobia as the most abundant phyla in wheat-rice rotation, whereas Actinobacteria, Firmicutes, Chloroflexi, Acidobacteria, Planctomycetes and Cyanobacteria were predominant in wheat-cotton rotation. From a total of 46,971 sequences, 10.9% showed ≥97% similarity with 16S rRNA genes of 32 genera previously shown to include isolates with plant growth promoting activity (nitrogen fixation, phosphate-solubilization, IAA production). Among these, the most predominant genera were Arthrobacter, Azoarcus, Azospirillum, Bacillus, Cyanobacterium, Paenibacillus, Pseudomonas and Rhizobium.

No MeSH data available.


Related in: MedlinePlus