المؤلفون: Gao, Nan¹ (AUTHOR), Yu, Xinchun² (AUTHOR), Yang, Siqi² (AUTHOR), Li, Qing² (AUTHOR), Zhang, Huanhuan³ (AUTHOR), Rajasekar, Adharsh⁴ (AUTHOR), Shen, Weishou^5,6 (AUTHOR) wsshen@nuist.edu.cn, Senoo, Keishi^7,8 (AUTHOR)

المصدر: Journal of Applied Microbiology. Oct2023, Vol. 134 Issue 10, p1-10. 10p.

مصطلحات موضوعية: *PLANT growth-promoting rhizobacteria, *ORGANIC fertilizers, *FERTILIZER application, *AGRICULTURE, *BACILLUS (Bacteria)

مستخلص: Aim: Organic fertilizer application significantly stimulates nitrous oxide (N2O) emissions from agricultural soils. Plant growth-promoting rhizobacteria (PGPR) strains are the core of bio-fertilizer or bio-organic fertilizer, while their beneficial effects are inhibited by environmental conditions, such as alkali and salt stress observed in organic manure or soil. This study aims to screen alkali- and salt-resistant PGPR that could mitigate N2O emission after applying strain-inoculated organic fertilizer. Methods and results: Among the 29 candidate strains, 11 (7 Bacillus spp., 2 Achromobacter spp., 1 Paenibacillus sp., and 1 Pseudomonas sp.) significantly mitigated N2O emissions from the organic fertilizer after inoculation. Seven strains were alkali tolerant (pH 10) and five were salt tolerant (4% salinity) in pure culture. Seven strains were selected for further evaluation in two agricultural soils. Five of these seven strains could significantly decrease the cumulative N2O emissions from Anthrosol, while six could significantly decrease the cumulative N2O emissions from Cambisol after the inoculation into the granular organic fertilizer compared with the non-inoculated control. Conclusions: Inoculating alkali- and salt-resistant PGPR into organic fertilizer can reduce N2O emissions from soils under microcosm conditions. Further studies are needed to investigate whether these strains will work under field conditions, under higher salinity, or at different soil pH. [ABSTRACT FROM AUTHOR]

المؤلفون: Fuentes-Quiroz, Alejandra, Herrera, Héctor, Alvarado, Roxana, Rabert, Claudia, Arriagada, Cesar, Valadares, Rafael Borges da Silva

المصدر: Journal of Applied Microbiology; Feb2024, Vol. 135 Issue 2, p1-13, 13p

مصطلحات موضوعية: PROTEACEAE, PHYTOPATHOGENIC fungi, MICROORGANISMS, PLANT growth-promoting rhizobacteria, AIR pollution, URBAN plants, PHYTOPATHOGENIC bacteria

مصطلحات جغرافية: ANDES

مستخلص: Aims This study aimed to evaluate and describe the functional differences of cultivable bacteria and fungi inhabiting the leaves of Gevuina avellana Mol. (Proteaceae) in an urban area with high levels of air pollution and in a native forest in the southern Andes. Methods and results Phyllosphere microorganisms were isolated from the leaves of G. avellana , their plant growth-promoting capabilities were estimated along with their biocontrol potential and tolerance to metal(loid)s. Notably, plants from the urban area showed contrasting culturable leaf-associated microorganisms compared to those from the native area. The tolerance to metal(loid)s in bacteria range from 15 to 450 mg l⁻¹ of metal(loid)s, while fungal strains showed tolerance from 15 to 625 mg l⁻¹, being especially higher in the isolates from the urban area. Notably, the bacterial strain Curtobacterium flaccumfaciens and the fungal strain Cladosporium sp. exhibited several plant-growth-promoting properties along with the ability to inhibit the growth of phytopathogenic fungi. Conclusions Overall, our study provides evidence that culturable taxa in G. avellana leaves is directly influenced by the sampling area. This change is likely due to the presence of atmospheric pollutants and diverse microbial symbionts that can be horizontally acquired from the environment. [ABSTRACT FROM AUTHOR]

: Copyright of Journal of Applied Microbiology is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Saikia, Juthika¹ (AUTHOR), Kotoky, Rhitu² (AUTHOR), Debnath, Rajal^1,3 (AUTHOR), Kumar, Niraj^1,4 (AUTHOR), Gogoi, Priyanka^1,4 (AUTHOR), Yadav, Archana¹ (AUTHOR), Saikia, Ratul^1,4 (AUTHOR) rsaikia19@gmail.com

المصدر: Journal of Applied Microbiology. Feb2023, Vol. 134 Issue 2, p1-14. 14p.

مصطلحات موضوعية: *PLANT growth-promoting rhizobacteria, *BLACK gram, *BEANS, *PROTEIN precursors, *PLANT growth, *RHIZOSPHERE

مستخلص: Aim Environmental stresses such as water deficit induced stress are one of the major limiting factors in crop production. However, some plant growth-promoting rhizobacteria (PGPR) can promote plant growth in such adverse condition. Therefore, the objective was to isolate rhizospheric bacteria from Phaseolus vulgaris L. growing in a drought-affected soil and to analyze its plant growth promoting (PGP) efficacy to black gram (Vigna mungo L.) and Bhut jolokia (Capsicum chinense Jacq.). Whole-genome sequencing of the potential bacteria was targeted to analyze the genetic potential of the isolate as a plant growth-promoting agent. Methods and results The isolate Enterobacter asburiae EBRJ12 was selected based on its PGP efficacy, which significantly improved plant growth and development. The genomic analysis revealed the presence of one circular chromosome of size 4.8 Mb containing 16 genes for osmotic stress regulation including osmotically inducible protein osmY, outer membrane protein A precursor ompA, aquaporin Z, and an operon for osmoprotectant ABC transporter yehZYXW. Moreover, the genome has a complete genetic cluster for biosynthesis of siderophore Enterobactin and siderophore Aerobactin. The PGP effects were verified with black gram and Bhut jolokia in pot experiments. The isolate significantly increased the shoot length by 35.0% and root length by 58.0% of black gram, while 41.0% and 57.0% of elevation in shoot and root length were observed in Bhut jolokia compared to non-inoculated plants. Conclusions The EBRJ12 has PGP features that could improve the growth in host plants, and the genomic characterization revealed the presence of genetic potential for plant growth promotion. [ABSTRACT FROM AUTHOR]

المؤلفون: Neemisha¹ (AUTHOR) neemisha14@pau.edu, Kumar, Arun² (AUTHOR) arunkumar@ihbt.res.in, Sharma, Poonam³ (AUTHOR), Kaur, Avneet¹ (AUTHOR), Sharma, Sandeep¹ (AUTHOR), Jain, Rahul² (AUTHOR) raahul.jain90@gmail.com

المصدر: Journal of Applied Microbiology. Nov2022, Vol. 133 Issue 5, p2694-2716. 23p.

مصطلحات موضوعية: *PLANT growth-promoting rhizobacteria, *COLONIZATION (Ecology), *RHIZOBACTERIA, *BACTERIAL communities, *MICROBIAL inoculants, *RHIZOSPHERE

مستخلص: Plant rhizo‐microbiome comprises complex microbial communities that colonize at the interphase of plant roots and soil. Plant growth‐promoting rhizobacteria (PGPR) in the rhizosphere provide important ecosystem services ranging from the release of essential nutrients for enhancing soil quality and improving plant health to imparting protection to plants against rising biotic and abiotic stresses. Hence, PGPR serve as restoring agents to rejuvenate soil health and mediate plant fitness in the facet of changing climate. Though it is evident that nutrient availability in soil is managed through inter‐linked mechanisms, how PGPR expedite these processes remain less recognized. Promising results of PGPR inoculation on plant growth are continually reported in controlled environmental conditions, however, their field application often fails due to competition with native microbiota and low colonization efficiency in roots. The development of highly efficient and smart bacterial synthetic communities by integrating bacterial ecological and genetic features provides better opportunities for successful inoculant formulations. This review provides an overview of the interplay between nutrient availability and disease suppression governed by rhizobacteria in soil followed by the role of synthetic bacterial communities in developing efficient microbial inoculants. Moreover, an outlook on the beneficial activities of rhizobacteria in modifying soil characteristics to sustainably boost agroecosystem functioning is also provided. [ABSTRACT FROM AUTHOR]

المؤلفون: Gao, Beibei^1,2 (AUTHOR), Chai, Xiaofen^1,2 (AUTHOR), Huang, Yimei^1,2 (AUTHOR), Wang, Xiaona^1,2 (AUTHOR), Han, Zhenhai^1,2 (AUTHOR), Xu, Xuefeng^1,2 (AUTHOR), Wu, Ting^1,2 (AUTHOR), Zhang, Xinzhong^1,2 (AUTHOR), Wang, Yi^1,2 (AUTHOR) wangyi@cau.edu.cn

المصدر: Journal of Applied Microbiology. Aug2022, Vol. 133 Issue 2, p720-732. 13p.

مصطلحات موضوعية: *ROOTSTOCKS, *PLANT growth-promoting rhizobacteria, *PLANT nutrition, *PSEUDOMONAS, *PLANT growth, *ROOT development, *IRON

مستخلص: Aims: The purpose of this study was to analyse the effects of siderophore‐producing bacteria and bacterial siderophore on the iron nutrition of apple rootstocks under iron‐deficient conditions. Methods and Results: We isolated three Pseudomonas strains, SP1, SP2 and SP3 from the rhizosphere of the Fe‐efficient apple rootstocks using the chrome azurol S agar plate assay. We found that all three strains had the ability to secrete indole acetic acid‐like compounds and siderophores, especially SP3. When Fe‐inefficient rootstocks treated with SP3 were grown in alkaline soil, an increase in the biomass, root development, and Fe concentration was observed in the plants. In addition, SP3 secreted pyoverdine, a siderophore that can chelate Fe3+ to enhance the bioavailability of Fe for plants. We purified the pyoverdine from the SP3 culture supernatant. Hydroponic experiments were conducted with a Fe‐deficient solution supplemented with pyoverdine, resulting in a reduction in the chlorosis caused by Fe deficiency and marked improvement in Fe uptake. Conclusions: Under iron‐deficient conditions, Pseudomonas sp. strain SP3 can effectively promote apple rootstock growth and improve plant iron nutrition by secreting siderophores that enhance Fe availability. Significance and Impact of the Study: This study showed that plant growth‐promoting rhizobacteria from Fe‐efficient plants have the potential to improve iron nutrition in Fe‐inefficient plants, and Fe‐siderophore chelates can be used as an effective source of iron for apple plants. Based on these findings, it may be possible to develop biological agents such as siderophore‐producing bacteria for sustainable agricultural and horticultural production. [ABSTRACT FROM AUTHOR]

المؤلفون: Alemneh, A.A.^1,2 (AUTHOR), Zhou, Y.^1,2 (AUTHOR) yi.zhou@adelaide.edu.au, Ryder, M.H.^1,2 (AUTHOR), Denton, M.D.^1,2 (AUTHOR) matthew.denton@adelaide.edu.au

المصدر: Journal of Applied Microbiology. Nov2021, Vol. 131 Issue 5, p2416-2432. 17p.

مصطلحات موضوعية: *PLANT growth, *PLANT growth-promoting rhizobacteria, *CHICKPEA, *PHOSPHATE rock, *PHOSPHATES, *RHIZOBACTERIA

مستخلص: Aims: Since most phosphate solubilizing bacteria (PSB) also produce 1‐aminocyclopropane‐1‐carboxylate (ACC) deaminase, we investigated if there was an association between these two plant growth‐promoting properties under in vitro conditions. Methods and Results: A total of 841 bacterial isolates were obtained using selective and enrichment isolation methods. ACC deaminase was investigated using in vitro methods and by sequencing the acdS gene. The effect of ACC deaminase on P solubilization was investigated further using five efficient PSB. ACC deaminase production ability was found amongst a wide range of bacteria belonging to the genera Bacillus, Burkholderia, Pseudomonas and Variovorax. The amount of ACC deaminase produced by PSB was significantly associated with the liberation of Pi from Ca‐P when ACC was the sole N source. Ca‐P solubilization was associated with the degree of acidification of the medium. Additionally, the P solubilization potential of PSB with (NH4)2SO4 was determined by the type of carboxylates produced. An in‐planta experiment was conducted using Burkholderia sp. 12F on chickpea cv. Genesis‐863 in sand : vermiculite (1 : 1 v/v) amended with rock phosphate and inoculation of this efficient PSB significantly increased growth, nodulation and P uptake of chickpea fertilized with rock phosphate. Conclusion: ACC deaminase activity influenced the capacity of PSB to solubilize P from Ca‐P when ACC was the sole N source and Burkholderia sp. 12F promoted the chickpea‐Mesorhizobium symbiosis. Significance and Impact of the Study: ACC deaminase activity could enhance the P solubilizing activity of rhizobacteria that improve plant growth. [ABSTRACT FROM AUTHOR]

المؤلفون: Alemneh, A. A.^1,2, Zhou, Y.^1,2 yi.zhou@adelaide.edu.au, Ryder, M. H.^1,2, Denton, M. D.^1,2 matthew.denton@adelaide.edu.au

المصدر: Journal of Applied Microbiology. Nov2020, Vol. 129 Issue 5, p1133-1156. 24p.

مصطلحات موضوعية: *PLANT growth-promoting rhizobacteria, *LEGUMES, *MEDICAGO, *INDOLEACETIC acid, *SYMBIOSIS, *NITROGEN fixation, *AGRICULTURAL productivity

مستخلص: Nitrogen fixation is an important biological process in terrestrial ecosystems and for global crop production. Legume nodulation and N2 fixation have been improved using nodule-enhancing rhizobacteria (NER) under both regular and stressed conditions. The positive effect of NER on legume--rhizobia symbiosis can be facilitated by plant growth-promoting (PGP) mechanisms, some of which remain to be identified. NER that produce aminocyclopropane-1-carboxylic acid deaminase and indole acetic acid enhance the legume--rhizobia symbiosis through (i) enhancing the nodule induction, (ii) improving the competitiveness of rhizobia for nodulation, (iii) prolonging functional nodules by suppressing nodule senescence and (iv) upregulating genes associated with legume--rhizobia symbiosis. The means by which these processes enhance the legume--rhizobia symbiosis is the focus of this review. A better understanding of the mechanisms by which PGP rhizobacteria operate, and how they can be altered, will provide opportunities to enhance legume--rhizobial interactions, to provide new advances in plant growth promotion and N2 fixation. [ABSTRACT FROM AUTHOR]

المؤلفون: Ji, C.¹ (AUTHOR), Wang, X.² (AUTHOR), Tian, H.¹ (AUTHOR), Hao, L.³ (AUTHOR), Wang, C.¹ (AUTHOR), Zhou, Y.¹ (AUTHOR), Xu, R.¹ (AUTHOR), Song, X.¹ (AUTHOR), Liu, Y.¹ (AUTHOR), Du, J.¹ (AUTHOR), Liu, X.¹ (AUTHOR) xlliu@sdau.edu.cn

المصدر: Journal of Applied Microbiology. Sep2020, Vol. 129 Issue 3, p695-711. 17p. 2 Color Photographs, 1 Black and White Photograph, 1 Diagram, 7 Charts.

مصطلحات موضوعية: *SOIL salinity, *PLANT growth-promoting rhizobacteria, *WHEAT, *SALINITY, *CROP yields, *WINTER wheat

مصطلحات جغرافية: CHINA

مستخلص: Aim: The aim of this study was to evaluate the ability of Bacillus methylotrophicus M4‐1 to protect winter wheat from the harmful effects of soil salinity and alkalinity. Methods and Results: We isolated the halotolerant B. methylotrophicus M4‐1. Two representative soils with different salt contents (S1, 213 μs cm−1; S2, 786 μs cm−1) in the Yellow River delta region of China were selected for experiments. The effects of the M4‐1 strain on the typical wheat variety (Jimai 21) in this environment were proven. In S1 soil, the M4‐1 strain reduced the wheat rhizosphere soil pH (1·61%) and electrical conductivity (EC) (8·01%) and increased the exchangeable K content (11·14%). The uptake of Mg2+ (20·73%) by wheat roots and K+ (8·84%) by leaves was increased, and the content of Na+ (23·62%) in leaves was reduced. In S2 soil, the M4‐1 strain was able to reduce soil EC (2·56%) and increase exchangeable K (11·20%) content. The absorption of K+ (13·28%) in wheat leaves was increased, and the content of Na+ (12·41%) in roots was decreased. Total N and organic matter contents in rhizosphere soil were significantly positively correlated with wheat growth and salt tolerance, whereas EC showed a significant negative correlation. Conclusions: M4‐1 attenuates salt stress injury in wheat under both low and high salt stress. Significance and Impact of the Study: We demonstrated the efficacy and value of plant growth‐promoting rhizobacteria addition to protect winter wheat against salt stress and improve crop yield. We also elucidated the physicochemical and biochemical interactions among M4‐1, the rhizosphere and the host plant. [ABSTRACT FROM AUTHOR]

المؤلفون: Ilyas, Noshin, Akhtar, Nosheen, Naseem, Aqsa, Qureshi, Rahmatullah, Majeed, Abid, Al‐Ansari, Mysoon M., Al‐Humaid, Latifah, Sayyed, R. Z., Pajerowska‐Mukhtar, Karolina M.

المصدر: Journal of Applied Microbiology; Dec2022, Vol. 133 Issue 6, p3307-3321, 15p

مصطلحات موضوعية: BACILLUS subtilis, HEAVY metal toxicology, PLANT growth-promoting rhizobacteria, PHOSPHATE fertilizers, CHROMIUM, WHEAT

مستخلص: Aim: Hexavalent chromium (Cr+6) is one of the most toxic heavy metals that have deteriorating effects on the growth and quality of the end product of wheat. Consequently, this research was designed to evaluate the role of Bacillus subtilis and phosphorus fertilizer on wheat facing Cr+6 stress. Methods and Results: The soil was incubated with Bacillus subtilis and phosphorus fertilizer before sowing. The statistical analysis of the data showed that the co‐application of B. subtilis and phosphorus yielded considerably more significant (p < 0.05) results compared with an individual application of the respective treatments. The co‐treatment improved the morphological, physiological and biochemical parameters of plants compared with untreated controls. The increase in shoot length, root length, shoot fresh weight and root fresh weight was 38.17%, 29.31%, 47.89% and 45.85%, respectively, compared with untreated stress‐facing plants. The application of B. subtilis and phosphorus enhanced osmolytes content (proline 39.98% and sugar 41.30%), relative water content and stability maintenance of proteins (86.65%) and cell membranes (66.66%). Furthermore, augmented production of antioxidants by 67.71% (superoxide dismutase), 95.39% (ascorbate peroxidase) and 60.88% (catalase), respectively, were observed in the Cr+6 – stressed plants after co‐application of B. subtilis and phosphorus. Conclusion: It was observed that the accumulation of Cr+6 was reduced by 54.24%, 59.19% and 90.26% in the shoot, root and wheat grains, respectively. Thus, the combined application of B. subtilis and phosphorus has the potential to reduce the heavy metal toxicity in crops. Significance and Impact of the Study: This study explored the usefulness of Bacillus subtilis and phosphorus application on wheat in heavy metal stress. It is a step toward the combinatorial use of plant growth–promoting rhizobacteria with nutrients to improve the ecosystems' health. [ABSTRACT FROM AUTHOR]

: Copyright of Journal of Applied Microbiology is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

المؤلفون: Bhat, Basharat Ahmad, Tariq, Lubna, Nissar, Showkat, Islam, Sheikh Tajamul, Islam, Shahid Ul, Mangral, Zahid, Ilyas, Noshin, Sayyed, Riyaz Z., Muthusamy, Govarthanan, Kim, Woong, Dar, Tanvir Ul Hasan

المصدر: Journal of Applied Microbiology; Nov2022, Vol. 133 Issue 5, p2717-2741, 25p

مصطلحات موضوعية: PLANT growth, ABIOTIC stress, STRESS management, PLANT growth-promoting rhizobacteria, RHIZOBACTERIA, BACILLUS (Bacteria), PLANT development, ACHROMOBACTER

مستخلص: The rhizosphere is the region around the plant roots where maximum microbial activities occur. In the rhizosphere, microorganisms' beneficial and harmful activities affect plant growth and development. The mutualistic rhizospheric bacteria which improve plant growth and health are known as plant growth‐promoting rhizobacteria (PGPR). They are very important due to their ability to help the plant in diverse ways. PGPR such as Pseudomonas, Bacillus, Azospirillum, Azotobacter, Arthrobacter, Achromobacter, Micrococcus, Enterobacter, Rhizobium, Agrobacterium, Pantoea and Serratia are now very well known. Rhizomicrobiome plays critical roles in nutrient acquisition and assimilation, improved soil texture, secreting and modulating extracellular molecules such as hormones, secondary metabolites, antibiotics and various signal compounds, all leading to the enhancement of plant growth and development. The microbes and compounds they secrete constitute valuable biostimulants and play pivotal roles in modulating plant stress responses. In this review, we highlight the rhizobacteria diversity and cutting‐edge findings focusing on the role of a PGPR in plant growth and development. We also discussed the role of PGPR in resisting the adverse effects arising from various abiotic (drought, salinity, heat, heavy metals) stresses. [ABSTRACT FROM AUTHOR]

: Copyright of Journal of Applied Microbiology is the property of Oxford University Press / USA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)