Significant Increase In Root Length Research Articles

Enhancement of wheat growth by plant growth-stimulating bacteria during phytopathogenic inhibition

Triticum spp. is grown widely all over the world, and numerous fungal diseases have a significant impact on the crop yield. Fusarium graminearum and Bipolaris sorokiniana are the most prevalent pathogens affecting wheat. In this study, the growth-stimulating bacteria in wheat are identified and their efficacy is examined in stimulating the growth of wheat seedlings under phytopathogenic conditions. In the course of the present investigation, four microorganisms that are resistant to the metabolites Fusarium graminearum and Bipolaris sorokiniana were isolated from wheat seeds. These strains were evaluated based on plant growth stimulation indicators, including the production of indole-3-acetic acid (0.4–3.3 mg×mL-1), gibberellic acid (116.9–431.5 μg×mL-1), siderophores (10.2–31.5%), phosphate solubilization (1.7–3.5), zinc solubilization (1.8–3.7), potassium solubilization (1.3–3.0) nitrogen fixation (250.0–840.0 μg×mL-1). In a laboratory experiment, two promising growth-stimulating bacteria that enhance the germination and development of wheat seeds under conditions of phytopathogenic stress were identified. When treated with the microorganisms, wheat seeds show a higher rate of germination, and a significant increase in root length was observed in the seedlings. A field test indicated that the presence of strains of Pantoea ananatis and Bacillus subtilis exerts a favorable effect on the wheat yield.

Effect of Phosphorus Levels on Early Seedlings of Rice (Oryza sativa) under Varying Moisture Stress Conditions

This study investigated the impact of moisture levels and phosphorus applications on different rice varieties. It aimed to: 1. Identify optimal rice varieties for specific moisture and phosphorus combinations. 2. Understand how moisture stress affects seed germination speed and root and shoot development. 3. Analyze the influence of increased phosphorus on root growth, especially under moisture stress. 4. Evaluate if additional NPK application enhances the positive effects of phosphorus. The meticulously controlled experiment, conducted within the International Rice Research Institute (IRRI)'s RGA facility from October to November 2023, utilized five rice varieties, three moisture levels (flooded, ideal, and Drought-like), and varying phosphorus levels. The findings revealed a positive correlation between phosphorus levels and root length across all rice varieties. This emphasizes the crucial role of phosphorus in promoting root development under challenging conditions. Notably, while increased phosphorus significantly enhanced root adhesion under flooding and aided seedling recovery, drought remained a significant barrier to root growth, regardless of phosphorus application. Interestingly, despite general genetic uniformity in germination and root-shoot parameters among the varieties, a clear positive correlation between phosphorus levels and root length was still observed. In conclusion, this study highlights the importance of phosphorus in strengthening root grip during floods, thereby aiding seedling recovery. However, it also emphasizes that drought remains a dominant factor hindering plant growth. The consistency observed across different rice varieties strengthens the findings, and the significant increase in root length with increased phosphorus application underscores its vital role in root development under challenging conditions. This study provides valuable insights for optimizing rice growth strategies by considering specific rice varieties, moisture levels, and phosphorus applications.

Evaluating Rhizobacterial Antagonists for Controlling Cercospora beticola and Promoting Growth in Beta vulgaris.

Cercospora beticola Sacc. is an ascomycete pathogen that causes Cercospora leaf spot in sugar beets (Beta vulgaris L.) and other related crops. It can lead to significant yield losses if not effectively managed. This study aimed to assess rhizosphere bacteria from sugar beet soil as a biological control agent against C. beticola and evaluate their effect on B. vulgaris. Following a dual-culture screening, 18 bacteria exhibiting over 50% inhibition were selected, with 6 of them demonstrating more than 80% control. The bacteria were identified by sequencing the 16S rRNA gene, revealing 12 potential species belonging to 6 genera, including Bacillus, which was represented by 4 species. Additionally, the biochemical and molecular properties of the bacteria were characterized in depth, as well as plant growth promotion. PCR analysis of the genes responsible for producing antifungal metabolites revealed that 83%, 78%, 89%, and 56% of the selected bacteria possessed bacillomycin-, iturin-, fengycin-, and surfactin-encoding genes, respectively. Infrared spectroscopy analysis confirmed the presence of a lipopeptide structure in the bacterial supernatant filtrate. Subsequently, the bacteria were assessed for their effect on sugar beet plants in controlled conditions. The bacteria exhibited notable capabilities, promoting growth in both roots and shoots, resulting in significant increases in root length and weight and shoot length. A field experiment with four bacterial candidates demonstrated good performance against C. beticola compared to the difenoconazole fungicide. These bacteria played a significant role in disease control, achieving a maximum efficacy of 77.42%, slightly below the 88.51% efficacy attained with difenoconazole. Additional field trials are necessary to verify the protective and growth-promoting effects of these candidates, whether applied individually, combined in consortia, or integrated with chemical inputs in sugar beet crop production.

Auxin Production by Bacillus simplex Enhanced the Growth of Zea mays (L.) under In-Vitro and In-Vivo Conditions

In the current study Bacillus simplex was evaluated for its role inimproving the growth of maize (Zea mays (L.)) under lab and natural environmental conditions. Bacterial strains were tested for several biochemical traits and auxin biosynthesis. Maize seeds were surface sterilized and treated with bacterial strains as single and mixed cultures to evaluate the enhancement of maize vegetative growth parameters. All bacterial strains exhibited positive results for catalase, citrate and nitrate while negative for urease, indole, triple sugar iron and oxidase test. Colorimetric analysis revealed significant production of auxin by Z-13 (6.7μg/ml), Z-09 (5.8μg/ml), Z-37 (5.7 μg/ml), Z-38 (5.7μg/ml), Z-02 (5 μg/ml), Z-37 (4.5 μg/ml)and Z-04 (3.5 μg /ml) at 1000μg/ml concentration of L-tryptophan. At 0 μg/ml conc of L-tryptophan, Z-37, Z-13, Z-04, Z-09and Z-38 also manifested significant levels of auxin biosynthesis. In-vitrorooting assay revealed that Z-09, Z-35 and Z-37 showed significant increase in root length i.e., 1.2, 1.18 and 1.11-fold, respectively, as compared to control. Pot trials under natural conditions manifested significant improvements in shoot length by Z-38 (67.1%), Z-13 (51%), and Z-09 (43%), over control. Most significant results for fresh weight (120%) and dry weight (100%) in maize were shown by strain Z-38. Among mixed cultures C-1 (Z-02, Z-04, Z-09) improved shoot length (42%) and fresh weight (45%) with respect to control. Improvement in vegetative growth parameters of maize suggests that B. simplex can be used as an effective biofertilizer.

Growth of alfalfa in the presence of metabolites from a dark septate endophyte strain Alternaria sp. 17463 cultured with a non-ionic surfactant and emulsifier.

Dark septate endophytes (DSE) was widely used in the agriculture and ecological restoration. The objective of this work was to assess the effect of culture media non-ionic surfactant and emulsifier on the biomass and metabolites of DSE strain Alternaria sp. 17463. Changes in the composition of DSE metabolites following the addition of Tween 80 during liquid culture of a DSE fungus were analyzed and used in growth tests of alfalfa.Shaking flask fermentation was carried out and the surfactant was fed to the fungus during the fermentation. The residual sugar content and pH declined significantly in the medium and the biomass of DSE increased by 7.27% over controls with no surfactant. Metabolomics analysis showed that adding the surfactant significantly increased the content of 63 metabolites (P<0.05). These include lipids and lipid-like molecules, organooxygen compounds, amino acids and organic acids, and flavonoids. Enrichment analysis of metabolic pathways indicates that surfactant addition promoted carbohydrate metabolism and amino acid synthesis. A plant hydroponic experiment indicated that these changes in metabolites altered the root structure of alfalfa seedlings. They also promoted significant increases in root length and root surface area, and increased alfalfa total biomass by 50.2%. Addition of the surfactant promoted sugar utilization by the DSE fungus and increased the synthesis of lipids and amino acids, resulting in the ability of the fungal metabolites to change root structure and promote plant growth.

Assessment on population of root knot nematode, Meloidogyne incognita and yield in brinjal using various bio agents under pot culture conditions

Brinjal (Solanum melongena) is one of the most important vegetables which has a great economic importance and also has a high processing value. Brinjals are susceptible to root-knot nematode (Meloidogyne incognita) leading to a great economic loss. The life cycle of root-knot nematode takes about 25 days to complete. Second stage juveniles J2 initiate infection in the host.Root-knot nematodes constitute a major group of plant-parasitic nematodes causing extensive economic damage to nearly all crop plants of economic importance in both tropical and subtropical crop production regions all over the world (Sikora and Fernandez 2005). The efficacy of different bioagents like Trichoderma viride, Bacillus subtilis, Pochoniac, hlamydosporia, Purpureocillium lilacinum against Meloidogyne incognita was estimated under four replications and assessment of plant morpho metric characters and root knot index under pot culture conditions has been recorded. All the four bio agents were tested in vitro to study their efficacy against Meloidogyne incognita. Among all the bioagents tested, Purpureocillium lilacinum treatment showed significant increase in root length and shoot length (35.11cm and 59.11cm, respectively) and the untreated control plants recorded the least root length and shoot length (12.02 cm and 15.12cm). All the treatments were found to reduce nematode population in roots and highest reduction was noticed in Purpureocillium lilacinum treated plants (161.11 and 138.10) soil (250g) and root (5g), respectively. The untreated plants recorded the highest nematode population of 1129.11 and 1259.20 in soil (250g) and root (5g) respectively. Singnificant reductionin root knot index (1.0) were observed in the treatment Purpureocillium lilacinum and Carbofuran which recorded (2.2 ) per cent. The untreated control plant roots showed a root knot index of 5.00 per cent.

Population of root knot nematode, Meloidogyne incognita and yield in tomato using various \bio agents under pot culture conditions

Tomato (Solanum lycopersicum) is one of the most important vegetable which has a great economic importance and also has a high processing value. Tomatoes are susceptible to root-knot nematode (Meloidogyne incognita) leading to a great economic loss. The life cycle of root-knot nematode takes about 25 days to complete. Second stage juveniles J2 initiate infection in the host. Root-knot nematodes constitute a major group of plant-parasitic nematodes causing extensive economic damage ton early all crop plants of economic importance in both tropical and sub-tropical crop production regions all over the world (Sikora and Fernandez, 2005). The efficacy of different bioagents like Trichoderma viride, Bacillus subtilis, Pochoniachlamy disporia, Purpureocillium lilacinum against Meloidogyn eincognita was estimated under four replications and assessment of plant morphometric characters and root knot index under pot culture conditions has been recorded. All the four bioagents were tested in vitro to study their efficacy against Meloidogyne incognita. Among all the bioagents tested, Purpureocillium lilacinum treatment showed significant increase in root length and shoot length (40.20cm and 76.20cm, respectively) and the untreated control plants recorded the least roo tlength and shoot length (19.11cm and 21.30cm). All the treatments were found to reduce nematode population in roots and highest reduction was noticed in Purpureocillium lilacinum treated plants (178.50 and 141.20) soil (250g) and root (5g), respectively. The untreated plants recorded the highest nematode population of 1314.14 and 1411.20 in soil (250g) and root (5g), respectively. Significant reduction in root knot index (1.2) were observed in the treatment Purpureocillium lilacinum and Carbofuran which recorded (2.0 ) per cent. The untreated control plant roots showed root knot index of 5.00 per cent.

Major-effect quantitative trait locus qLKR4.1 encodes a phospholipase Dδ protein associated with low-K+ stress tolerance by promoting root length

qLKR4.1, controlling low K+ resistance in tomato, was fine-mapped to an interval of 67.5kb on chromosome A04, and one gene encoding phospholipase Dδ was identified as a candidate gene. In plants, changes in root length are an important morphological response to low K+ (LK) stress; however, the underlying genetics in tomato remain unclear. Here, we combined bulked segregant analysis-based whole-genome sequencing, single-nucleotide polymorphism haplotyping, and fine genetic mapping to identify a candidate gene as a major-effect quantitative trait loci (QTL), i.e., qLKR4.1, which was associated with LK tolerance due to increased root elongation in the tomato line JZ34. Through multiple analyses, we found that Solyc04g082000 is the most likely candidate for qLKR4.1, which encodes phospholipase Dδ (PLDδ). Increased root elongation under LK in JZ34 may be attributed to a non-synonymous single-nucleotide polymorphism in the Ca2+-binding domain region of this gene. Solyc04g082000 increases root length through its PLDδ activity. Silencing of Solyc04g082000Arg in JZ34 led to a significant decrease in root length compared with silencing of Solyc04g082000His allele in JZ18 under LK conditions. Mutation of a Solyc04g082000 homologue in Arabidopsis, pldδ, resulted in decreased primary root lengths under LK conditions, compared to the wild type. Transgenic tomato expressing the qLKR4.1Arg allele from JZ34 exhibited a significant increase in root length compared with the wild type expressing the allele from JZ18 under LK conditions. Taken together, our results confirm that the PLDδ gene Solyc04g082000 exerts important functions in increasing tomato root length and LK tolerance.

Mesoporous silica nanoparticle-induced drought tolerance in Arabidopsis thaliana grown under in vitro conditions.

Nanoparticles of varying formats and functionalities have been shown to modify and enhance plant growth and development. Nanoparticles may also be used to improve crop production and performance, particularly under adverse environmental conditions such as drought. Nanoparticles composed of silicon dioxide, especially those that are mesoporous (mesoporous silica nanoparticles; MSNs), have been shown to be taken up by plants; yet their potential to improve tolerance to abiotic stress has not been thoroughly examined. In this study, a range of concentrations of MSNs (0-5000mgL-1) were used to determine their effects, in vitro, on Arabidopsis plants grown under polyethylene glycol (PEG)-simulated drought conditions. Treatment of seeds with MSNs during PEG-simulated drought resulted in higher seed germination and then greater primary root length. However, at the highest tested concentration of 5000mgL-1, reduced germination was found when seeds were subjected to drought stress. At the optimal concentration of 1500mgL-1, plants treated with MSNs under non-stressed conditions showed significant increases in root length, number of lateral roots, leaf area and shoot biomass. These findings suggest that MSNs can be used to stimulate plant growth and drought stress tolerance.

Modified pulpotomy procedure in immature permanent teeth with apical periodontitis: a randomised controlled trial

ObjectivesThe objective of this study was to evaluate the effectiveness of a modified pulpotomy (MP) procedure in immature permanent teeth with apical periodontitis (AP).DesignRandomised controlled trial.SettingOne public hospital in Shanghai,...

Potassium Humate and Plant Growth-Promoting Microbes Jointly Mitigate Water Deficit Stress in Soybean Cultivated in Salt-Affected Soil.

Lack of high-quality irrigation water and soil salinity are two main environmental factors that affect plant development. When both stressors are combined, the soil becomes sterile and constrains plant productivity. Consequently, two field trials were designed to assess whether plant growth-promoting microbes (PGPMs; Bradyrhizobium japonicum (USDA 110) and Trichoderma harzianum) and potassium humate (K-humate) can stimulate soybean growth, productivity, and seed quality under two different watering regimes as follows: (i) well-watered (WW), where plants were irrigated at 12-day intervals (recommended), and (ii) water stress (WS), where plants were irrigated at the 18-day intervals in salt-affected soil during 2020 and 2021 seasons. Results revealed that coupled application of PGPMs and K-humate resulted in a substantial improvement in K+ levels in the leaves compared to Na+ levels, which has a direct positive impact on an enhancement in the antioxidants defense system (CAT, POX, SOD), which caused the decline of the oxidative stress indicators (H2O2, MDA, and EL%) as well as proline content under water stress in salt-affected soil. Hence, a significant increase in root length, nodule weight, soybean relative water content (RWC), stomatal conductance, photosynthetic pigments, net photosynthetic rate, soluble protein, seed carbohydrate content as well as the number of pods plant-1 and seed yield was reported. In conclusion, the combined application of PGPMs and K-humate might be recommended to maximize the soybean growth and productivity under harsh growth conditions (e.g., water stress and soil salinity).

Unravelling the potential plant growth activity of halotolerant Bacillus licheniformis NJ04 isolated from soil and its possible use as a green bioinoculant on Solanum lycopersicum L.

Immensely expanding world population and narrowing arable land for agriculture is a mighty concern faced by the planet at present. One of the major reasons for decline in arable lands is the increased soil salinity, making it unfavourable for crop cultivation. Utilisation of these saline land for agriculture is possible with suitable invention for improving the soil quality. Biofertizers manufactured out of Plant Growth Promoting Rhizobacteria is one such innovation. In the present study, Bacillus licheniformis NJ04 strain was isolated and studied for its halotolerance and other effective plant growth promoting traits. The NJ04 strain was able to tolerate salt up to 10% and highlighted remarkable antifungal activity against common fungal phytopathogens. The preliminary seed germination test in Solanum lycopersicum seeds revealed a significant increase in root length (16.29 ± 0.91 cm) and shoot length (9.66 ± 0.11 cm) of treated plants as compared with the control plants and thereby shows its possible use as a green bioinoculant in agriculture and an ideal candidate to compete with salt stress.

Melatonin enhanced low-temperature combined with low-light tolerance of pepper (Capsicum annuum L.) seedlings by regulating root growth, antioxidant defense system, and osmotic adjustment.

Melatonin (MT) is an important biologically active hormone that plays a vital role in plant growth and development. In particular, it has been investigated for its roles in abiotic stress management. In this study, pepper seedlings were subjected to low-temperature combined with low-light stress (LL) (15/5°C, 100 μmol m-2s-1) prior to a foliar spray of 200mM MT for 168h to investigate the protective role of MT in pepper seedlings. Our results demonstrated that LL stress negatively affected root growth, and accelerated the accumulation of reactive oxygen species (ROS), including H2O2 and , changed the osmolytes contents, and antioxidative system. However, these were reversed by exogenous MT application. MT effectively promoted the root growth as indicated by significant increase in root length, surface area, root volume, tips, forks, and crossings. In addition, MT reduced the burst of ROS and MDA contents induced by LL, enhanced the activities of SOD, CAT, POD, APX, DHAR, and MDHAR resulted by upregulated expressions of CaSOD, CaPOD, CaCAT, CaAPX, CaDHAR, and CaMDHAR, and elevated the contents of AsA and GSH, declined DHA and GSSH contents, which prevented membrane lipid peroxidation and protected plants from oxidative damages under LL stress. Furthermore, seedlings treated with MT released high contents of soluble sugar and soluble protein in leave, which might enhance LL tolerance by maintaining substance biosynthesis and maintaining cellular homeostasis resulted by high levels of osmolytes and carbohydrate in the cytosol. Our current findings confirmed the mitigating potential of MT application for LL stress by promoting pepper root growth, improving antioxidative defense system, ascorbate-glutathione cycle, and osmotic adjustment.

Evaluation of Different Fertilizer Types in the Suppression of Root Knot Nematode Infection on Sweet Potato (Ipomoea batatas) in Makurdi, Benue State

A field experiment was conducted at the Agronomy Teaching and Research Farm, Federal University of Agriculture Makurdi in the 2020/2021 planting season. To evaluate the effects of different fertilizer types in the control of root knot nematode of sweet potato. The experiment was laid out in a randomized complete block design (RCBD). The treatments were Liquid fertilizer (Super gro) and poultry dropping and control which were replicated three times. Before the treatments were applied, soil samples were collected for nematode extraction and the nematodes were extracted in the laboratory using the modified Bearmann tray technique. Super gro and geese droppings were applied at 2 weeks interval and 4 weeks interval. The results show a significant (p&lt;0.05) reduction of root gall index, significant increase in root length, weight of roots and number of roots on the plots treated with fertilizer. This research work recommends the application of poultry droppings for the management of root knot nematode in sweet potato (Ipomoea batatas).

Endodontic pulp revitalization in traumatized necrotic immature permanent incisors: Early failures and long-term outcomes-A longitudinal cohort study.

AimThis prospective cohort study evaluates clinical and radiographical outcomes of endodontic pulp revitalization (PR) of traumatized necrotic incisors.MethodologyPulp revitalization was performed in 75 traumatized necrotic immature incisors from 71 patients. The radiographic outcome measures were continued root formation (width and length), root resorption, apex closure, periapical index, and root development stage. The clinical outcome measures were percussion pain, palpation pain, pathological tooth mobility, swelling, sinus tract, ankylosis, crown discolouration, response to pulp sensitivity test, and subjective pain. Treatment outcomes were categorized as a success based on the absence of clinical symptoms and when radiographic evidence was present for apical healing and continued root development. The performed statistical tests were repeated measures anova, pairwise comparisons of interactions (t‐test), McNemar's test, and linear regression model.ResultsIn 45 of 75 teeth (60%), PR was successful with the resolution of clinical and radiographic signs and continued root development. PR failed due to the absence of bleeding (n = 19) and persistent infection (n = 11). PR showed statistically significant increases in root length (11%), and dentinal wall thickness (30%), root maturation (pre‐operative 3.38 [CI 1.88; 4.88]; post‐operative 4.04, [CI 2.56; 5.52]) apical closure (71.4%), healing of pre‐operative apical periodontitis (100%), and healing of pre‐operative inflammatory root resorptions (100%). Three predictive variables for continued root maturation were identified – root development stage at entry (p = .0001, β 0.649), [CI 0.431; 0.867], trauma to the soft tissues (p = .026, β −0.012), [CI −0.0225; −0.015], and pre‐operative dentinal wall thickness (p = .009, β −0.001); [CI −0.001; 0.0001].ConclusionsOur findings indicate that PR provides satisfactory clinical and radiographical outcomes in traumatized necrotic incisors. The failed cases were related to lack of bleeding and persistent infections, indicating that new techniques are needed to improve the predictability of PR.

Do alternative scaffolds used in regenerative endodontics promote better root development than that achieved with blood clots?

The aim of this integrative review was to identify whether alternative scaffolds used in regenerative endodontics contribute to better root development, in relation to the increase in root length and thickness of dentin walls, compared with blood clot (BC) scaffolds. The literature search was conducted in PubMed, SciELO and Lilacs databases, using descriptors related to the topic. After applying the eligibility criteria, 11 articles were selected and analyzed according to the proposed aim. Five clinical and six in vivo studies, conducted in animals, compared different types of alternative scaffolds with BCs, with emphasis on platelet-rich plasma (PRP) and platelet-rich fibrin (PRF). All scaffolds, alternative or BC, promoted an increase in root length and dentin wall thickness, with varying percentages of increase between studies. In general, there was a significant increase in root length and dentin thickness promoted by PRF and PRP scaffolds, compared with BC. It was concluded that the majority of the scaffolds tested contributed to the increase in root length and thickness of dentin walls, with emphasis on PRF and PRP.

An Evaluation of Aluminum Tolerant Pseudomonas aeruginosa A7 for In Vivo Suppression of Fusarium Wilt of Chickpea Caused by Fusarium oxysporum f. sp. ciceris and Growth Promotion of Chickpea.

Chickpea wilt, caused by Fusarium oxysporum f. sp. ciceris, is a disease that decreases chickpea productivity and quality and can reduce its yield by as much as 15%. A newly isolated, moss rhizoid-associated Pseudomonas aeruginosa strain A7, demonstrated strong inhibition of Fusarium oxysporum f. sp. ciceris growth. An in vitro antimicrobial assay revealed A7 to suppress the growth of several fungal and bacterial plant pathogens by secreting secondary metabolites and by producing volatile compounds. In an in vivo pot experiment with Fusarium wilt infection in chickpea, the antagonist A7 exhibited a disease reduction by 77 ± 1.5%, and significantly reduced the disease incidence and severity indexes. Furthermore, A7 promoted chickpea growth in terms of root and shoot length and dry biomass during pot assay. The strain exhibited several traits associated with plant growth promotion, extracellular enzymatic production, and stress tolerance. Under aluminum stress conditions, in vitro growth of chickpea plants by A7 resulted in a significant increase in root length and plant biomass production. Additionally, hallmark genes for antibiotics production were identified in A7. The methanol extract of strain A7 demonstrated antimicrobial activity, leading to the identification of various antimicrobial compounds based on retention time and molecular weight. These findings strongly suggest that the strain’s significant biocontrol potential and plant growth enhancement could be a potential environmentally friendly process in agricultural crop production.

Selection and Characterization of Burkholderia spp. for Their Plant-Growth Promoting Effects and Influence on Maize Seed Germination

Burkholderia sp. is a bacterial genus extremely versatile in the environment and has been reported for a great potential to promote plant growth via different mechanisms. Here we evaluate the plant growth-promoting mechanisms in twenty-six Burkholderia strains. Strains were evaluated for their ability to promote plant growth by means of: indole-3-acetic acid (IAA) production under different conditions of pH, salt stress and the presence or absence of L-tryptophan; exopolysaccharides (EPS) production and quorum sensing (ALH). The strains were also characterized in terms of their genetic variability and species identification through Sanger sequencing. Then, the bacteria most responsive in the greatest number of plant-growth promotion mechanisms were selected for a corn seed germination test. All bacteria synthesized IAA in medium with 0.0 or 5.0 mM of L-tryptophan in combination with either 1 or 5% of NaCl, and pH values of either 4.5 or 7.2. The EPS production was confirmed for 61.54% of the bacterial strains. Quorum sensing also occurred in 92.3% of the selected bacteria. The Jaccard similarity coefficient revealed 16 clusters with high genetic variability between bacterial strains. Bacterial strains were assigned to seven species: B. anthina, B. cepacia, B. gladioli, B. ambifaria, B. graminis, B. heleia, and Burkholderia spp. The corn seed bacterization did not affect the germination velocity index (GSI), as well as the first count of germinated seeds (FC). However, inoculations formulated with B. heleia strain G28, B. gladioli strain UAGC723, and B. graminis strain UAGC348 promoted significant increases in root length, seedling height and fresh and dry seedling phytomass, respectively. These results indicate the high biotechnological potential of several strains in the genus Burkholderia sp. as seed inoculants, favoring germination and seedling initial development.

A Prospective Study of Long-Term Regenerative Endodontics Outcomes of Necrotic Immature Permanent Teeth: An 8-Year Follow-Up.

For the management of necrotic immature teeth, regenerative endodontics offers the advantage of further root lengthening, thickening of dentin wall, and apical closure. This prospective study aimed to evaluate the long-term outcome of regenerative endodontics in immature necrotic permanent teeth. A total of 23 immature roots were medicated by triple antibiotic paste. After 21 days, bleeding was induced by over-instrumentation, and then mineral trioxide aggregate and coronal restoration were applied. Patients were scheduled for clinical and radiographic follow-up for 8 years. The radiographic changes of root dimensions were assessed using the ImageJ Plugin and statistically analyzed by Kruskal–Wallis test at a 95% confidence level. For qualitative evaluation, images were overlapped and analyzed using Photoshop software. All teeth were asymptomatic one month after the treatment. All teeth (n = 18) with preoperative periapical radiolucency showed complete resolution within 6–9 months. Recall rate at two, three, and eight years was 69.6%, 56.5%, and 34.8%, respectively. Continuous root development with a significant increase in root length and thickening of dentin wall accompanied by a significant decrease in apical canal diameter was seen at the end of the observation period (p < 0.001). In conclusion, the long-term outcome of regenerative endodontics revealed successful clinical and radiographic results with appropriate case selection.

Performance of Actinobacteria isolated from rhizosphere soils on plant growth promotion under cadmium toxicity

This work aimed to evaluate the potential use of plant growth-promoting actinobacteria (PGPA) for enhanced cadmium (Cd) phytoremediation and plant growth. Forty-two actinobacteria were isolated from rhizosphere soils in Thailand. Among isolates tested, only Streptomyces phaeogriseichromatogenes isolate COS4, showed the high ability to produce siderophores as a plant growth stimulant and had a strong Cd tolerance potential. The significance of siderophores production and Cd tolerance ability under different Cd concentrations suggests the potential of isolate COS4 to work effectively. Plant culture revealed that the significant increase in root length, root to tip length, and total dried weight of sunflower were obtained after 2 h incubation of sunflower seeds with isolate COS4. The efficiency of Cd uptake was found to range between 42.3 and 61.3%. Translocation factor results confirmed that plant growth promoting S. phaeogriseichromatogenes isolate COS4-assisted phytoremediation can be considered as Cd absorbents for the restoration of polluted sites due to high translocation values.