Cherry blossom crown gall has caused serious damage to plant growth, and is highly contagious and extremely difficult to control. The antagonism of pathogens by rhizosphere bacteria has attracted widespread attention. However, there is still limited research on the cherry blossom crown gall. In this study, we explored the control effect of rhizosphere bacteria Pseudomonas aurantiaca ST-TJ4 on cherry blossom crown gall. We also investigated the long-term survival status of ST-TJ4 in the cherry blossom roots and the induction of plant defense resistance. The results showed that ST-TJ4 had obvious inhibition effect on the population of Agrobacterium tumefaciens, which could reduce the number of A. tumefaciens by 70% to 90%, and its population kept the advantage in the rhizosphere soil and cherry blossom roots. The incidence of crown gall in the therapy group and the prevention group was reduced by 37.5% and 50%, respectively, and the disease index was reduced from 80 to 20 and 10, respectively. At the 150th day, ST-TJ4 could still be isolated from the rhizosphere soil and root surface, indicating that ST-TJ4 could survive in soil for a long time and had long-term performance. Compared with the control group, the therapy group and prevention group could reduce the levels of H2O2, malondialdehyde (MDA) and the oxidative damage, and up-regulated the expression of active oxygen-related genes DHAR1, SOD1, GR1 and CAT to activate defense response. On the other hand, it could up-regulate the expression of SA1, SA2 and JA1 genes related to the induction of salicylic acid (SA) and jasmonic acid (JA), and lead to the increase of SA hormone level. Collectively, P. aurantiaca ST-TJ4 had the potential to be applied for biocontrol of cherry blossom crown gall by reducing root pathogen colonization and inducing plant resistance.

Pesticide contamination has become a major environmental concern with organophosphates such as chlorpyrifos emerging as major pollutants posing significant risks to both ecosystems and human health. Chlorpyrifos is widely used in agriculture to control pests, however due to its persistence, its accumulation in soils can lead to long-term environmental damage. The objective of this study was to isolate and characterize chlorpyrifos-degrading bacteria from a tobacco field exposed to intensive pesticide use in T & uuml;rkiye. To achieve this, a selective enrichment strategy was employed to promote the growth of chlorpyrifos-degrading microorganisms. Two distinct experimental setups were established to target both normally growing and slower-growing bacteria: the first involved a 4-week incubation with weekly subculturing as described in the literature, while the second applied an 8-week incubation with biweekly subculturing. At the end of the enrichment period, bacterial loads were compared between the two groups. Four of the nine bacterial isolates were obtained from the newly tested long-term setup. Among all isolates, members of the genus Pseudomonas exhibited the best adaptation to the prolonged enrichment conditions. Additionally, isolates belonging to the genera Klebsiella, Sphingobacterium, and Peribacillus were isolated from the normally growing group. Two isolates (AB4 & AB15), identified as Sphingobacterium thalpophilum, were determined to be novel chlorpyrifos degraders. This is the first reported study from T & uuml;rkiye focusing on the biodegradation of chlorpyrifos by native soil bacteria. The findings revealed that various ecological areas, constitute potential sources for new microbial metabolic processes and these bacterial strains can be used in bioremediation studies.

Root-knot nematode (RKN) causes severe yield loss in cucumber. Understanding the interactions of biocontrol agent-soil microbiomes and RKNs is essential for enhancing the efficacy of biocontrol agents and nematicides to curb RKN damage to cucumber. The field experiment in this work was conducted to determine the ability of Bacillus velezensis GHt-q6 to colonize cucumber plants, investigate its effect on the control of RKNs, and assess its influence on soil microbiology in the inter-root zone of cucumber plants. After 10 days post-treatment (DPT), GHt-q6-Rif could stably colonize the roots (4.55 x 10(4) cfu center dot g(-1)), stems (3.60 x 10(3) cfu center dot g(-1)), and leaves (3.60 x 10(2) cfu center dot g(-1)) of cucumber. The high-throughput sequencing results suggested that the bacterial community diversity increased at the late development phase (p > 0.05). The strain GHt-q6 increased the relative abundance of beneficial bacteria (Gemmatimonadaceae, Sphingomonadaceae, Pseudomonadaceae). Throughout the complete cucumber growth period, strain GHt-q6 significantly increased soil urease, sucrase, accessible potassium, and phosphorus (p < 0.05). However, strain GHt-q6 had a minimal effect on catalase activity. At the pulling stage, strain GHt-q6 exhibited 43.35% control effect on cucumber RKNs, which was 7.54% higher than that of Bacillus subtilis. The results highlighted the significant potential of the strain GHt-q6 to manage cucumber RKNs and improve soil microecology. Hence, the applications of B. velezensis GHt-q6 can enhance the nematicidal action to curb RKN infecting cucumber.

The use of plant growth-promoting microorganisms is an effective agricultural practice to improve plant growth, especially under abiotic stress. In this study, the combined impact of three plant growth-promoting bacteria (PGPB) namely Brevibacterium halotolerans (Sd-6), Burkholderia cepacia (Art-7), Bacillus subtilis (Ldr-2) were tested with Trichoderma harzianum (Th) (possessing ACC deaminase producing activity) in Ocimum basilicum L. cv. Saumya to reduce drought-induced damages to the plants under different level of drought stress [i.e. wellwatered (100 %), moderate (60 %), severe (40 %)]. These PGPB strains, along with Th, were found to be tolerant against osmotic stress when tested in growth media containing different concentrations of polyethylene glycol (PEG 8000), and all were found to endure -0.99 MPa water potential. Compared to non-inoculated control, Th+Ldr-2 treatment improved fresh herb weight (62.45 %) and oil content (61.54 %) and higher photosynthetic rate under severe drought. Besides, in relation to control, the above treatment enhanced nutrient uptake, reduced ABA, ACC as well as ethylene levels and increased IAA content in addition to an increase in important constituents of essential oil, indicating better performance in terms of plant growth under drought. Higher RWC, decreased MDA, and reduced antioxidant activities in Th+Ldr-2 treated plants compared to non-inoculated control under drought support the mechanism of the microbes providing tolerance against drought. Colony forming unit of microbes and scanning electron microscopy (SEM) study support the effective colonisation behaviour of Th+Ldr-2, which protects plants against drought stress. A consortium of diverse microbes, found to improve plant growth under drought through increased nutrient uptake, reducing the levels of ACC and ABA, improving the content of IAA, antioxidant enzymes probably reducing the effect of drought stress and improving plant biomass could be a useful tool to reduce drought-induced losses in crop plants.

This research aims to isolate and identify calcite-precipitating bacteria and investigate whether they can be used in concrete to enhance its mechanical qualities and self-healing capabilities. Microbial-induced precipitation of calcium carbonate is a new technique for making cement concrete stronger. The present study aims to compare cement concrete's compressive and split-tensile strengths to those of conventional concrete to examine the possible use of alkaliphilic bacteria to improve its qualities and ability to self-repair hairline cracks in concrete. Through conducting experiments on concrete samples at ages 7, 28, and 56 days, to which the isolated bacteria were added and characterized at the molecular level using the AccuPrep Genomic DNA Extraction kit, amplified, and subjected to agar gel electrophoresis, the sequences were obtained and compared with those in the GenBank database using the BLAST tool in the NCBI-GenBank database. Using PCR and scanning electron microscopy, it was confirmed that the isolated alkaline bacteria had a 99.69% identity rate. The bacteria Alkalibacterium iburiense were used at different concentrations of 105and 108. Additionally, 2% of recycled coarse aggregate and 10% & 20% was used. It was found that the concrete properties were improved. It was determined that the optimum improvement in mechanical properties was with the addition of bacteria at a concentration of 108 and a total recycled aggregate ratio of 10% after 56 days. The compressive, tensile, and flexural strengths increased by 25.75%, 17.27%, and 19.4%, respectively.

Phosphonates (PHTs), organic compounds with a stable C-P bond, are widely distributed in nature. Glyphosate (GP), a synthetic PHT, is extensively used in agriculture and has been linked to various human health issues and environmental damage. Given the prevalence of GP, developing cost-effective, on-site methods for GP detection is key for assessing pollution and reducing exposure risks. We adopted Agrobacterium tumefaciens CHLDO, a natural GP degrader, as a host and the source of genetic parts for constructing PHT biosensors. In this bacterial species, the phn gene cluster, encoding the C-P lyase pathway, is regulated by the PhnF transcriptional repressor. We selected the phnG promoter, which displays a dose-dependent response to GP, to build a set of whole-cell biosensors. Through stepwise genetic optimization of the transcriptional cascade, we created a whole-cell biosensor capable of detecting GP in the 0.25-50 mu M range in various samples, including soil and water.

PurposeRot disease caused by Fusarium poses a formidable threat to the growth of saffron (Crocus sativus L.), resulting in substantial damage to both yield and quality. It is paramount to delve into the root causes of rot disease in saffron to optimize both yield and quality. Existing preventive and treatment modalities have exerted deleterious effects on corms and the natural environment. Consequently, the quest for efficacious and eco-friendly methods such as biological control agents has become an urgent imperative. MethodsThe disparate distribution of microbial communities between rhizospheric microorganisms and saffron serves as the foundational exploration for uncovering the underlying causes of rot disease. Samples from various saffron organs and rhizosphere soil were gathered, and the sequencing data from the microbial communities were interpreted using 16S rRNA and ITS gene sequencing methods. This facilitated an in-depth examination of the composition and changes of microorganisms in both healthy and diseased saffron plants. ResultsThe findings indicated rot disease reduced the abundance and diversity of microorganisms in saffron, and the fungal co-occurrence networks were less stable and their communities were more sensitive to rot disease than the bacterial community. Fusarium was the predominant genus in diseased samples, accounting for 99.19% and 89.77% of the communities in diseased leaves and corms. With corms and leaves displaying heightened susceptibility to infection compared to other plant organs. Some of the beneficial bacterial taxa enriched in the diseased plants were also identified in networks, they showed an antagonistic relationship with Fusarium, suggesting a potential for these bacteria to be used in biologically based control strategies against rot disease. These insights could prove invaluable for the development of biocontrol agents aimed at combating this plant ailment. ConclusionThese findings significantly advance our understanding of saffron-microbiome interactions and could provide fundamental and important data for improving saffron yield and quality in the process of sustainable development.

Plastic pollution is a common concern of global environmental pollution. Polystyrene (PS) and polyethylene (PE) account for almost one-third of global plastic production. However, so far, there have been few reports on microbial strains capable of simultaneously degrading PS and PE. In this study, Microbacterium esteraromaticum SW3, a non-pathogenic microorganism that can use PS or PE as the only carbon source in the mineral salt medium (MM), was isolated from plastics-contaminated soil and identified. The optimal growth conditions for SW3 in MM were 2% (w/v) PS or 2% (w/v) PE, 35 degrees C and pH 6.3. A large number of bacteria and obvious damaged areas were observed on the surface of PS and PE products after inoculated with SW3 for 21 d. The degradation rates of PS and PE by SW3 (21d) were 13.17% and 5.39%, respectively. Manganese peroxidase and lipase were involved in PS and PE degradation by SW3. Through Fourier infrared spectroscopy detection, different functional groups such as carbonyl, hydroxyl and amidogen groups were produced during the degradation of PS and PE by SW3. Moreover, PS and PE were degraded into alkanes, ketones, carboxylic acids, esters and so on detected by GC-MS. Collectively, we have isolated and identified SW3, which can use PS or PE as the only carbon source in MM as well as degrade PS and PE products. This study not only provides a competitive candidate strain with broad biodegradability for the biodegradation of PS and/or PE pollution, but also provides new insights for the study of plastic biodegradation pathways.

Cinnamaldehyde is a natural compound extracted from cinnamon bark essential oil, acclaimed for its versatile properties in both pharmaceutical and agricultural fields, including antimicrobial, antioxidant, and anticancer activities. Although potential of cinnamaldehyde against plant pathogenic bacteria like Agrobacterium tumefaciens and Pseudomonas syringae pv. actinidiae causative agents of crown gall and bacterial canker diseases, respectively has been documented, indepth studies into cinnamaldehyde's broader influence on plant pathogenic bacteria are relatively unexplored. Particularly, Pectobacterium spp., gram -negative soil -borne pathogens, notoriously cause soft rot damage across a spectrum of plant families, emphasizing the urgency for effective treatments. Our investigation established that the Minimum Inhibitory Concentrations (MICs) of cinnamaldehyde against strains P. odoriferum JK2, P. carotovorum BP201601, and P. versatile MYP201603 were 250 pg/ml, 125 pg/ml, and 125 pg/ml, respectively. Concurrently, their Minimum Bactericidal Concentrations (MBCs) were found to be 500 pg/ml, 250 pg/ml, and 500 pg/ml, respectively. Using RNA -sequencing analysis, we identified 1,907 differentially expressed genes in P. carotovorum BP201601 treated with 500 pg/ml cinnamaldehyde. Notably, our results indicate that cinnamaldehyde upregulated nitrate reductase pathways while downregulating the citrate cycle, suggesting a potential disruption in the aerobic respiration system of P. carotovorum during cinnamaldehyde exposure. This study serves as a pioneering exploration of the transcriptional response of P. carotovorum to cinnamaldehyde, providing insights into the bactericidal mechanisms employed by cinnamaldehyde against this bacterium.

PECTOBACTERIUM and Dickeya species are the main causative agents for soft rot disease that adversely affect fruits and vegetables leading to considerable economic losses. Biological management with beneficial microorganisms is a promising alternative to hazardous bactericides. Therefore, the antagonistic activity of two different strains of Rahnella aquatilis was in vitro and in vivo evaluated against nine soft rotting bacterial strains. The antagonistic soil bacteria R. aquatilis strains 17 and 55 restricted the growth of nine soft rotting bacterial strains on nutrient agar plates, (7 Pectobaterium carotovorum strains and 2 Dickeya chrysanthmi strains). Transmission electron micrographs of P. carotovorum Pep3B cells antagonized with R. aquatilis strain 17, showed damaged cells with disrupted plasma membrane releasing the cellular contents. To examine whether R. aquatilis 17 could be an effective biological control agent for pepper soft rot disease, two applications were conducted. The pepper seedlings were pretreated, before the pathogen, with R. aquatilis 17 through leaves and roots. All seedlings pretreated with the antagonistic strain 17 showed reduced susceptibility towards the P. carotovorum Pep3B, increased fresh, dry weights and seedlings' height relative to controls. R. aquatilis 17 inoculation has positively influenced the physiological parameters evaluated, such as chlorophyll content, carotenoids, phenolics, flavonoids, protein concentration as well as proline concentration. The obtained results revealed that R. aquatilis 17 mitigated the effect of P. carotovorum on pepper seedlings and promoted their growth, which means that it has a high probability of being an effective biological control agent and a plant-promoting bacterium.