Day 1 Tue, January 11, 2022最新文献

{"title":"Impact of Delayed Flowback on Well Performance: Case Study","authors":"R.. Al Shidhani, A. Al Shueili, Hussain Al Salmi, M. Jaboob","doi":"10.2118/205269-ms","DOIUrl":"https://doi.org/10.2118/205269-ms","url":null,"abstract":"\u0000 Due to a resource optimization and efficiency improvements, wells that are hydraulically fractured in the tight gas Barik Formation of the Khazzan Field in the Sultanate of Oman are often temporarily left shut-in directly following a large scale massive hydraulic fracturing stimulation treatment. Extensive industry literature has often suggested (and reported), that this may result in a significant direct loss of productivity due to the delayed flowback and the resulting fracture conductivity and formation damage. This paper will review the available data from the Khazzan Field address these concerns; indicating where the concerns should and should not necessarily apply.\u0000 The Barik Formation in the Khazzan Field is an over-pressured gas-condensate reservoir at 4,500 m with gas permeability ranging from 0.1 to 20 mD. The average well after hydraulic fracturing produces 25 MMscfd and 500 bcpd against a wellhead pressure of 4,000 psi. A typical hydraulic fracturing stimulation treatment consists of 14,000 bbl of a borate-crosslinked guar fluid, placing upwards of 1MM Lbs of high conductivity bauxite proppant within a single fracture. In order to assess the potential production loss due to delayed flowback operations, BP Oman performed a suite of formation damage tests including core samples from the Barik reservoir, fracture conductivity considerations and dynamic behaviors. Additionally, normalized production was compared between offset wells that were cleaned-up and put onto production at different times after the hydraulic fracturing operations.\u0000 Core tests showed a range of fracture conductivities over time with delayed flowback after using the breaker concentrations from actual treatments. As expected, enhanced conductivity was achieved with additional breaker. The magnitude of the conductivity being created in these massive treatments was also demonstrated to be dominant with respect to damage effects. Finally, a normalized comparison of an extensive suite of wells clearly showed no discernible loss of production resulted from any delay in the flowback operations.\u0000 This paper describes in details the workflow and resulting analysis of the impact of extensive shut-in versus immediate flowback post massive hydraulic fracturing. It indicates that the impact of such events will be limited if the appropriate steps have been taken to minimize the opportunity for damage to occur. Whereas the existing fracturing literature takes the safe stance of indicating that damage will always result from such shut-ins, this paper will demonstrate the limitations of such assumptions and the flexibility that can be demonstrated with real data.","PeriodicalId":11087,"journal":{"name":"Day 1 Tue, January 11, 2022","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80117568","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel In-Situ Gelled Acid System Based on Inorganic Nanoparticles","authors":"R. Kalgaonkar, Q. Sahu, Nour Baqader","doi":"10.2118/205336-ms","DOIUrl":"https://doi.org/10.2118/205336-ms","url":null,"abstract":"\u0000 Gelled acid systems based upon gelation of hydrochloric acid (HCl) are widely used in in both matrix acidizing and fracture acidizing treatments to prevent acidizing fluid leak-off into high permeable zones of a reservoir. The gelled up fluid system helps retard the acid reaction to allow deeper acid penetration for hydrocarbon productivity enhancement. The in-situ gelation is typically achieved by using crosslinked polymers with the acid. Conventional in-situ crosslinked gelled acid systems are made up of polyacrylamide gelling agent, iron based crosslinker and a breaker chemical in addition to other additives, with the acid as the base fluid. However, the polymer-based systems can lead to damaging the formation due to a variety of reasons including unbroken polymer residue. Additionally, the iron-based crosslinker systems can lead to scaling, precipitation and or sludge formation after the acid reacts with the formation, resulting in formation damage and lowering of hydrocarbon productivity.\u0000 In this paper we showcase a new nanoparticles based gelled acid system that overcomes the inherent challenges faced by conventional in-situ crosslinked gelled acid systems. The new system can work in 5 to 20 % HCl up to 300°F. The new system does not contain any polymer or iron based crosslinker that can potentially damage the formation. It comprises nanoparticles, a gelation activator, acidizing treatment additives along with HCl. The new in-situ gelled acid system has low viscosity at surface making it easy to pump. It gels up at elevated temperatures and pH of 1 to 4, which helps with diverting the tail end acid to tighter or damaged zones of the formation. We demonstrate that the viscosification and eventual gelation of the new system can be achieved as the acid reacts with a carbonate formation and the pH rises above 1. As the acid further reacts and continues to spend there by increasing the pH beyond 4, the gel demonstrates reduction of viscosity. This assists in a better cleanup post the acidizing treatment.\u0000 Various experimental techniques were used to showcase the development of the nanoparticle based acid diversion fluid. Static and dynamic gelation studies as a function of time, temperature and pH are reported. The gelation performance of the new system was evaluated at temperatures up to 300°F and discussed in the paper. Comparative performance of different types of gelation activators on the gelation profile of the nanoparticles is evaluated. It is also shown that the gelation and viscosity reduction is entirely a pH dependent phenomenon and does not require any additional breaker chemistry, and therefore provides more control over the system performance.\u0000 The novelty of the new gelled acid system is that it is based upon nanoparticles making it less prone to formation damage as compared to a crosslinked polymer based system.","PeriodicalId":11087,"journal":{"name":"Day 1 Tue, January 11, 2022","volume":"6 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87880549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The effects of fertirrigation and Azospirillum brasilense inoculation on photosynthetic compounds of Agave angustifolia","authors":"Domitila Jarquín- Rosales, J. E. Valle, Juan José Alpuche- Osorno, Gerardo Rodríguez Ortíz, Meredith P. Martin, G. V. C. Ángeles","doi":"10.21475/ajcs.22.16.01.p3280","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.01.p3280","url":null,"abstract":"Agave angustifolia is the most important species of the genus Agave in Oaxaca, Mexico for its use as raw material for the production of mescal. However, research is lacking on the best agricultural methods for growing this species, including on the most effective fertilizer rates and on the use on bacterial inoculation. Our objective was to evaluate the production of photosynthetic compounds in A. angustifolia plants originating from seeds when they were fertilized by irrigation and inoculated with Azospirillum brasilense. An experiment was carried out in a completely randomized design with a 3×2 factorial arrangement, with the type of irrigation factor at three levels: 1) water; 2) a Steiner nutrient solution composed of N, P, K and micronutrients at 50%; and 3) the nutrient solution at 100%. Subsequently, each irrigation group was separated into two subgroups to evaluate them under the effect of the second factor, inoculation with A. brasilense: 1) inoculated plants; 2) control plants not inoculated for a total of six treatments with 20 plants (replications) per treatment. In each treatment we quantified Chlorophyll a, b and total, Rubisco, and sugars content in foliar samples, as well as the acidity attributed to malic acid at 8:00 and 16:00 hours. We found that plants fertilized and inoculated had bigger leaves with higher amount of Chlorophyll a, b and total and higher amounts of sugars and Rubisco compared to both plants unfertilized and without inoculation and to plants with just fertilization or just inoculation alone. Furthermore, the highest acidity value attributed to malic acid occurred during the first hours of the morning, in the plants of all treatments, but more noticeable in those plants fertirrigated with more nutrient solution (100%) and inoculated with A. brasilense. We therefore advise using both fertilization and inoculation for greater growth and accumulation of photosynthetic compounds in A. angustifolia","PeriodicalId":11087,"journal":{"name":"Day 1 Tue, January 11, 2022","volume":"69 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86095335","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gas exchange in bacurizeiro (Platonia insignis Mart.) genotypes in the dry and rainy seasons in the Middle North region of Brazil","authors":"Clemilton da Silva Ferreira, W. E. Pereira, L. Vasconcelos, R. Vivian, J. Ribeiro, O. J. Smiderle, A. D. G. Souza, T. J. Dias, M. L. S. Leal, Adjair J. da Silva","doi":"10.21475/ajcs.22.16.01.p3271","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.01.p3271","url":null,"abstract":"The bacurizeiro (Platonia insignis Mart.) is a species of great economic and social importance in the North and Middle North regions of Brazil. However, little is known about the environmental effects on its physiological characteristics. The objective of this work was to determine the gas exchange of genotypes of bacurizeiro in the dry and rainy seasons in the Middle North region of Brazil. The experiment was conducted in the Embrapa Meio Norte experimental field, located in Teresina-Piauí. A completely randomized design in a 7x2 factorial scheme was used, with seven genotypes and two seasons (dry and rainy), with three replications. The genotypes were M1MP14p12f1, M1MP14p13f1, M2PP2p18f5, M3MP6p14f1, M3MP6p15f1, M4MP6p7f4 and M7PP5p18f3 from the improvement program of Embrapa Meio Norte. Liquid photosynthesis, stomatal conductance, transpiration and internal CO2 concentration, ratio between internal CO2 concentration and ambient CO2 concentration, intrinsic water use efficiency and instant water use efficiency were evaluated. The environmental variation affects the plasticity of the bacurizeiro genotypes. There is less efficiency in the use of water in the dry period in all genotypes of bacurizeiro, with values between 1.20 and 1.55 µmol CO2 m-2 s-1 / µmol H2O m-2 s-1, respectively. The genotypes M1MP14p13f1, M2PP2p18f5 and M7PP5p18f3 are the most stable in the face of environmental variations, since in both seasons they are in the same formed groups","PeriodicalId":11087,"journal":{"name":"Day 1 Tue, January 11, 2022","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90323106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of potassium fertilizers doses on the growth, tuber yield, and resistance to weevil infestation of sweet potato on Latosol soil","authors":"Suwarto, H. Aswidinoor, Fajar Gustian Reyzaldi","doi":"10.21475/ajcs.22.16.01.p3375","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.01.p3375","url":null,"abstract":"Major problems in sweet potato (Ipomoea batatas L.) cultivation are low yield and high weevil (Cylas formicarius) infestation. The effect of potassium (K) on growth and yield has been intensively reported. However, there is less information on the correlation between K and the resistance to weevil infestation. The aim of the research was to determine the optimum dose of K fertilizers for maximum tuber yield and minimum weevil infestation Sweet potato var. Ase Kapas was planted with a K dose of 0, 45, 90, 135, and 180 kg K2O ha-1. The experiment was conducted using a randomized block design with 4 replications in January – July 2020 at Latosol soil. The experimental plot was 4m x 2m which was divided into 4 ridges. Stem cuttings were planted on the center of the ridge with a 0.20 m spacing. Variables of growth, tuber yield, and level of weevil infestation were observed at 3 weeks after planting and at harvest. There were significant quadratic responses of yield variables to the K application. It is recommended the use of 125 kg K2O ha-1 can provide the highest tuber yield and a significant reduce of weevil infestation level. At the K dose of 125 kg K2O ha-1 , tuber yield increased by 179 % (357.4 g plant-1, compared to the control of 127.9 g plant-1) and the weevil infested tuber was reduced as much as 61.6 % (from 6.46, at the control dose to 2.37 tuber plant-1).","PeriodicalId":11087,"journal":{"name":"Day 1 Tue, January 11, 2022","volume":"289 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83434982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cotton resistance to white mold (Sclerotinia sclerotiorum) evaluated by the oxalic acid method","authors":"Matheus Rodrigues Martins, D. Cardoso, D. Bortolin, E. Lemes, E. G. S. Júnior, A. F. Nascimento, Lucas Rodrigues Martins, L. B. Sousa","doi":"10.21475/ajcs.22.16.01.p2804","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.01.p2804","url":null,"abstract":"The white mold (Sclerotinia sclerotiorum) is one of the most destructive cotton disease. Genetic resistance is one of the main strategies to control this disease. Thus, this study aimed to determine an appropriate period of exposition and concentration of oxalic acid to identify levels of physiological resistance to white mold in white fiber cotton genotypes. The study was implemented in two periods (August to October and November to January) in randomized complete block design, in a split-split-plot factorial in time, with five replications, where the plot factor was the concentration of oxalic acid (20; 40 mM) and the sub-plot factor was the 20 cotton genotypes, the sub-sub-plot factor was the time of exposure to oxalic acid (24h; 48h; 72h). The experimental units, or plots, were composed of test tubes with one cotton plant shoot partially immersed in oxalic acid solution. The biomass of the cotton shoots was evaluated at 24, 48, and 72 h. The loss of water caused by the exposure to oxalic acid indirectly indicates the level of cotton resistance to white mold. The results suggest that the most appropriate exposition time and concentration of oxalic acid for cotton evaluation of resistance to white mold were 20 mM at 48 hours, respectively. In these conditions, the cotton genotypes that presented the greatest average fresh mass were: UFU-14 A, UFU-14 B, UFU-14 F, UFU-14 H, and UFU-14 S, which could be used as sources of resistance to white mold in cotton breeding programs","PeriodicalId":11087,"journal":{"name":"Day 1 Tue, January 11, 2022","volume":"72 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85590458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using salinity to improve nutritional and market value of strawberries","authors":"M. Alnayef, Joseph Hartley, F. Orsini, R. D. Silvestro, Rabab Sanoubar, I. Marotti, G. Gianquinto, G. Dinelli, Norhawa Puniran- Hartley","doi":"10.21475/ajcs.22.16.01.p2910","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.01.p2910","url":null,"abstract":"Plants respond to salinity by producing antioxidants and osmolytes; some of these are nutritionally useful to humans (e.g. phenolics), or may improve the sensory quality of produce (e.g. sugars). For the current study, strawberries were irrigated with 0, 10, 20 or 40 mM NaCl, and the responses in antioxidants, phenolics, and flavour attributes were measured. A linear positive relationship was observed between salt stress and antioxidant concentrations, and the DPPH antioxidant assay responded more clearly than the FRAP assay. Phenolics were increased with statistical significance by salinity at all treatment levels, although trends differed between total phenolics and the subclasses anthocyanins and total flavonoids. It was seen that mild salinity (10 mM) with a low impact on yield could be used to increase antioxidants (6-10% above control) and total phenolics (11-16% above control). However differences between cultivars outweighed differences due to salinity in treatments below 20 mM NaCl. We found that sugars in strawberries (unlike other fruits) weren’t increased by salinity treatment. The lack of sugar increase can be explained by suggesting that organic acids are more important osmolytes than sugars for strawberries under salinity. However it was also determined that the failure of strawberries to increase their soluble sugars during salt stress can be explained by the lean nutrient regimes used by researchers, which don’t represent commercial production practices. Practically, mild salinity (≤20 mM) can be used to increase strawberry fruit value, but should be combined with an appropriate nutrient regime to avoid harm to flavour quality. The varieties Elsanta and Elsinore are both suitable for salt treatment, but Elsanta is better for antioxidant and phenolic production, as well as being more salt tolerant","PeriodicalId":11087,"journal":{"name":"Day 1 Tue, January 11, 2022","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81967120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pod shattering incidence in relation to seed dispersal and maximum harvest delay in soybean genotypes","authors":"A. Krisnawati, A. Soegianto, Budi Waluyo, Kuswanto","doi":"10.21475/ajcs.22.16.01.p2950","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.01.p2950","url":null,"abstract":"The efforts to minimize the pod shattering incidence in soybean can be done by the use of resistant variety and the determination on the limit of harvest delay. The study aims to evaluate the pod shattering resistance and to determine the maximum limit for harvest delay in soybean. Sixteen soybean genotypes were planted during the dry season 2019. After plants reached the F8 phase, ten randomly sample plants were taken from each plot. The examination for the effect of the harvest delay on the pod shattering incidence was based on the simulation on the pot. The experiment was arranged in a randomized block design with four replications. Pod shattering on each fertile node and seed dispersal were observed for twenty days. The number of fertile nodes, number of pods per fertile node, and pod shattering on the fertile node varied between genotypes. The highest number of pods where found at the third node (7.50a ± 4.26) and fourth node (7.44a ± 4.23) from the lower part of the stem. Pod shattering in the nodes at the lower part of the stem (17 % ± 4.96 %) was higher than in the nodes at the middle (8% ± 6.86%), and upper part of the stem (3% ± 3.79%). The evaluation for pod shattering resistance resulted in two very resistant genotypes, ten resistant, two moderately resistant, one susceptible, and one very susceptible genotype. The seed dispersal of very resistant and resistant genotypes ranged from 0 - 8.55%, the moderately resistant genotypes were 12 – 15%, and the susceptible and very susceptible genotypes were between 23.72 – 48.65%. The harvest delay in resistant or very resistant genotypes could be done 20 days after maturity, meanwhile in susceptible and very susceptible genotypes, the harvest delay should not exceed three days after maturity","PeriodicalId":11087,"journal":{"name":"Day 1 Tue, January 11, 2022","volume":"293 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79519222","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adequacy of the electrical conductivity test on Libidibia ferrea seeds (Mart. Ex Tul.) L. P. Queiroz var. ferrea classified with different masses","authors":"P. C. Souto, J. C. A. Neto, V. M. Ferreira, E. P. Gonçalves, Cristian Bernardo da Silva, Karolyne Priscila Oliveira dos Santos, J. C. F. M. Junior, Lucas Teles Bezerra","doi":"10.21475/ajcs.22.16.01.p3329","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.01.p3329","url":null,"abstract":"This study aimed to adapt the methodology of the electrical conductivity test to detect differences in vigor between seeds of Libidibia ferrea of different masses. The seeds were classified according to their individual mass: small seeds ≤ 0.14 g, medium seeds 0.15 ≤ x ≤ 0.19, large seeds ≥ 0.20 g. Subsequently, seed morphology (length, width, thickness, water content, and weight of 1000 seeds), and the initial physiological potential of the seeds (germination, first count, average time, average speed, germination rate coefficient, germination and emergence rate index, emergence percentage, seedling length, and dry mass) were determined. The electrical conductivity was conducted in a 3 × 12 factorial scheme with three seed masses and 12 immersion periods (2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, and 24 h), in volumes of 50 and 75 mL of water, with 25 and 50 seeds, respectively. The physical and physiological variables of the seeds were highly correlated with the electrical conductivity test. The seed mass of L. ferrea has a direct relationship with its physiological potential, with the seeds of mass ≥ 0.20 g classified with high vigor; the seeds of mass 0.15 ≤ x ≤ 0.19 with intermediate vigor; and the seeds of mass ≤ 0.14 g with low vigor. The electrical conductivity test is efficient in the evaluation of the physiological potential of L. ferrea seeds of different masses when conducted with 25 seeds soaked in 50 mL of distilled water for 4 h","PeriodicalId":11087,"journal":{"name":"Day 1 Tue, January 11, 2022","volume":"13 11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85493322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Isolation of endophytic bacteria from wild plants in dry regions and investigation of their ability to promote plant growth and inhibit pathogenic fungi","authors":"K. E. Hamed","doi":"10.21475/ajcs.22.16.01.p3400","DOIUrl":"https://doi.org/10.21475/ajcs.22.16.01.p3400","url":null,"abstract":"In the dry regions environments such as Saudi Arabia, bacterial endophytes isolated from the roots and soil of healthy wild plants can promote plant growth by developing siderophores, phosphate solubilizing, Indole 3 Acetic Acid (IAA), and inhibit the growth of some plant fungal pathogens. This study aimed to isolate bacteria from wild plants in dry regions and to investigate their ability to be used as plant growth-promoting agent and inhibit plant pathogenic fungi. More than ninety endophytic bacterial isolates associated with the leaves, roots, and soil of healthy wild plants were collected from different sites in the Qassim region, Kingdom of Saudi Arabia, with the aim of characterizing and testing for their ability to promote plant growth activities and inhibit plant pathogenic fungi. Seventy strains were shown to produce indole-3-acetic acid (IAA) and 45 isolates produced siderophores, with 16 of these exhibiting large amounts. Twelve isolates tested positive for phosphate solubilization, with two isolates (QUSA 66 and QUSA 91) exhibiting greater efficiency for phosphate solubility. Twenty-five isolates produced more than 100 µg mL-1 of IAA, with production ranging from 100.5 to 404.7 µg mL-1. Six of these bacterial isolates (QUSA 2, 7, 10, 29, 30. and 40) produced more than 200 µg mL-1. A wide spectrum of activities was noted within the pseudomonas strains, indicating promising plant growth-promoting potential (e.g., the isolates from Pulicaria crispa and Calligonum comosum). In vitro results against plant pathogenic fungi showed that fifteen of the bacterial isolates inhibited growth of fungal mycelia by producing wide antagonistic zones. The isolates QUSA 26, 27, 28, 36, and 87 were able to produce siderophores and IAA and to solubilize phosphate. In addition, these isolates delayed mycelium growth of some Fusarium, Rhizoctonia solani, Botrytis, and Stemphylium spp","PeriodicalId":11087,"journal":{"name":"Day 1 Tue, January 11, 2022","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77826346","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}