Suppression of maize root diseases caused by Macrophomina phaseolina

Microbiol. Res. (2001) 156,209–223

http://www.urbanfischer.de/journals/microbiolres

Suppression of maize root diseases caused

by Macrophomina phaseolina,Fusarium moniliforme and Fusarium graminearum by plant growth promoting rhizobacteria K. K. Pal, K. V. B. R. Tilak, A. K. Saxena, R. Dey, C. S. Singh

Division of Microbiology, Indian Agricultural Research Institute, New Delhi-110 012, India

Accepted:January 25, 2001

Abstract

0944-5013/01/156/03-209$15.00/0Microbiol. Res. 156(2001) 3209

seases. However, only Macrophomina phaseolina (charcoal rots), Fusarium moniliforme (Gibberella fujikuroi, foot rots and wilting) and Fusarium grami-nearum(Gibberella zeae, root rots, stalk rots and wilt-ing) cause substantial damage to the crop in several areas. Since there are no cultivars with complete resis-tance to soil-borne fungal pathogens in maize, and fungicides are not potent enough to protect the crop from infection by these pathogens, development of bio-control agents could be the best alternative to minimize the incidence of these diseases. Application of Bacillus sp. has been found to substantially control seedling blight, root rots and stalk rots of maize caused by Fusarium graminearum,when used as seed inoculant (Chang and Kommedahl 1968; Kommedahl and Chang 1975). Trichod erma virid e and Pseudomonas species were also capable of controlling stalk rots of maize (Chen et al.1999). Application of root-associated Pseudomonas cepacea as seed coating biocontrol agent could reduce the Fusarium moniliforme-induced infec-tion of maize root by 23–80% (Hebbar et al.1992a, b). Pseudomonas cepacea was also found to inhibit a range of soil-borne fungal pathogens including Fusarium graminearum,Fusarium moniliforme and Macro-phomina phaseolina(Hebbar et al.1992b). Burkhol-d eria cepacea was also found potent in controlling Fusarium moniliforme besides plant growth promotion of maize (Bevivino et al.1998). Raju et al.(1999) re-ported the reduction of Fusarium moniliforme-induced diseases of maize by application of Trichoderma har-zianum,Pseud omonas fluorescens and Chaetomium globosum.Incidence of charcoal rot was substantially reduced after seed treatment of mungbean and sun-flower by Trichoderma harzianum,Gliocladium virens and Streptomyces sp. (Hussain et al.1990). Sanchez et al.(1994) reported the potency of Burkholderia cepacea UPR5c to control ashy-stem blight of common bean.

Plant growth promoting Pseudomonas and Bacillus species generally employ an array of mechanisms like antibiosis, site competition, production of HCN, chiti-nase, siderophore, ammonia, fluorescent pigments and/or antifungal volatiles (Weller 1988; V oisard et al. 1989; Cartwright et al.1995; Gardener et al.2000; Pal et al.2000) to antagonize pathogens. In the present study, an attempt has been made to identify suitable biocontrol agents against maize pathogens, Macro-phomina phaseolina,Fusarium moniliforme and Fusarium graminearum,and to isolate the compounds responsible for suppression of the pathogens. Thus, three plant growth promoting rhizobacterial (PGPR) isolates (a fluorescent Pseudomonas sp. EM85 and two Bacillus spp., MR-11 (2) and MRF) obtained from maize rhizosphere, were found to antagonize and sup-press Fusarium moniliforme,Fusarium graminearum and Macrophomina phaseolina-induced diseases of maize and Rhizoctonia solani-induced damping-off of cotton (Pal 1995, Pal et al.2000). Potent antifungal compounds from these isolates have also been ob-tained.

Material and methods

Strains.The isolates of Macrophomina phaseolina, Fusarium moniliforme and Fusarium graminearum, virulent on maize, were obtained from Indian Type Culture Collection (ITCC), Division of Mycology and Plant Pathology, Indian Agricultural Research Institute (IARI), and were maintained on Potato Dextrose Agar (PDA) slants at 4°C, and subcultured monthly. A fluo-rescent Pseudomonas sp. EM85 (obtained from maize endorhizosphere) and two bacilli isolates MRF (having proteinase activity) and MR-11(2) (having proteinase and lipase activity) isolated from maize rhizosphere, exhibiting antifungal and other plant growth promoting traits were maintained at 4°C. The generation time of EM85, MR-11(2) and MRF were 56 min, 54 min and 90 min, respectively. The phenotypes and some im-portant characteristics of the isolates are depicted in Table 1. The bacterial isolates were grown at 28°C in nutrient broth or potato dextrose broth. E. coli S17-1 (pSUP:Tn-B20) harbouring Tn5::lac Z was grown at 37°C in Tryptone-Yeast extract (TY) broth amended with kanamycin (50 μg ml–1). The E. coli strain used was sensitive to nalidixic acid.

Detection of antifungal traits.The isolates of fluorescent Pseudomonas sp. and Bacillus spp. were screened to detect the production of chitinase (F randberg and Schnurer 1994), HCN (Bakker and Schipper 1987), antifungal volatiles (Howell et al. 1988), siderophore (Schwyn and Neilands 1987), anti-fungal antibiotics (Hebbar et al.1992) and fluorescent pigments (Pal et al.2000) as described elsewhere (Pal et al.2000). Each test was repeated three times with three replications.

Quantification of plant growth promoting traits. Nitrogenase activity, assayed as acetylene reduction activity (ARA), was estimated using a gas chromato-graph (Shimadzu GC-14A). Nitrogenase activity was expressed as nmoles of ethylene produced tube–1h–1. The organisms were grown in 5 ml of liquid and solid complex carbon medium (Rennie 1981) in 20-ml tubes at 28 ±2°C for 24 h. Tubes were sealed with serum stoppers and 10% acetylene was injected into each tube after taking out 10% air from each tube. Again, tubes were incubated for 24 h at 28 ±2°C. After the incuba-tion, production of ethylene was measured by GC.

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Catechol type of siderophore was quantified by the method of Arnow (1937), modified by Carson et al. (1992) in iron-free liquid medium. Absorbance was determined at 550 nm with pyrocatechol as standard. Quantification of IAA-like substances was made following the method of Sarwar and Kremer (1995) in L-tryptophan agar. One ml of the isolates grown for 24 h in Kings’B (King et. al.1954) broth was plated onto L-tryptophan agar in triplicates and incubated at 28±2°C for 24 h in the dark. After incubation, an agar growth bead (0.24 cc) was placed in freshly prepared Salkowsky reagent, in triplicates, from each Petri dish and incubated in the dark for 30 min. Spectrophoto-metric reading was taken at 595 nm with IAA as stan-dard. The amount of IAA produced was expressed as μg ml–1.

Solubilization of tri-calcium phosphate was quanti-fied in Pikovskaya broth (Pikovskaya 1948). Each flask containing 100 ml of Pikovskaya broth with 50 mg tri-calcium phosphate was inoculated with 0.5 ml of each isolate (grown for 24 h in liquid culture) and incubated in a rotary shaker at 28 ±2°C for 4 d. The cultural broth was centrifuged at 15,000 rpm for 10 min and the supernatant was collected in 100-ml volumetric flasks. The volume of the supernatant was adjusted to 100 ml with distilled water. Water-soluble phosphorus was determined in the supernatant by the chloromolybdic acid method of King (1932) as modified by Jackson (1967). Spectrophotometric measurement was taken at 660 nm.

The organic acids produced by the biocontrol agents were detected by paper chromatography after reducing the volume of the supernatant in a lyophilizer to 1/40th volume, obtained during the phosphate solubilization experiment. Standard organic acids were dissolved in deionized water (30 mg ml–1). Spots were made on Whatman No. 1 filter paper and chromatography was run in a solvent system of n-butanol:acetic acid:water (12:3:5) for 14 h. The spots were developed as descri-bed by Nordmann and Nordmann (1960) by spraying bromocresol green reagent (100 mg in 250 ml of abso-lute alcohol at 7.0 pH).

Tn5::lac Z mutagenesis,selection and maintenance of mutants.Transposon (Tn5::lac Z) mutagenesis was car-ried out by biparental mating as described by Simon et al.(1983) for introduction of DNA from E. coli(donor) to the fluorescent Pseudomonas sp. EM85 (recipient). Conjugation was carried out at 1:1 ratio (donor:reci-pient) on Tryptone-Yeast extract (TY) agar Petri dishes for 18–20 h at 28°C. Transconjugants were selected on TY Petri dishes amended with kanamycin and nalidixic

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Table1.Characteristics of the isolates and strains used in the experiments*.

Isolate Catechol nmoles IAA like TCP Organic Phenotypes Source

sidero-C

2H

4

substances solubili-acids

phore h–1tube–1(μg ml–1)zation produced

(mg mg–1(mg

protein)100–1ml)

Fluorescent0.092 6.76 3.8414.13Gluconic,Afa+HCN+Pal Pseudomonas Citric,Sid+Flu+(1995) isolate EM85Succinic, α-

(Km s ketobutyric

Nal r Cm r)**

Isogenic0.091 6.58 3.9030.08Gluconic,Afa+HCN+-Do-Tn5:: lac Z Citric,Sid+Flu+

mutant, M23,Succinic, α-

of the isolate ketobutyric

EM85

Bacillus sp.0.108––––Afa+Afv+-Do-MR-11(2)Sid+

(Ap r)

Bacillus sp.0.08433.57 3.7125.70Gluconic,Afa+Sid+-Do-MRF(Km r Citric,

Tet r)Tartaric, α-

ketobutyric

E. coli S17-1–––––harbouring Simon (Km r)Tn5::lac Z et al.

1983 *Data represent average of three replications repeated thrice.

**Km = Kanamycin; Nal = Nalidixic acid; Ap = Ampicillin; Tet:Tetracycline.

acid (50 μg ml–1) along with IPTG (four μl of 200 mg ml–1stock) and X-gal (40 μl of 20 mg ml–1in dimethyl-formamide stock). Blue colonies were picked as puta-tive mutants whereas colourless colonies were dis-carded as spontaneous mutants. All the mutants were screened for V oges-Proskauer (VP) test, which was negative for the fluorescent Pseudomonas sp. EM85 and positive for E. coli in order to eliminate the spon-taneous mutants of E. coli. Mutants were maintained in TY slants amended with kanamycin (50 μg ml–1) and nalidixic acid (50 μg ml–1) at 4°C.

Phenotypic characterisation of mutants.Mutants were screened for antifungal traits such as production of HCN, siderophores, fluorescent pigments and antifun-gal antibiotics as described earlier. All the parameters mentioned were studied in media containing kanamycin and nalidixic acid (50 μg ml–1). Inhibition zones were measured in mm against the pathogen on PDA and NA. Mutants deficient in antifungal antibiotic production were checked in NA. For the determination of antifun-gal antibiotics, cyanide and fluorescent pigments one mutant each was grown on one Petri dish, whereas for assay of siderophore production several mutants were spotted in a single Petri dish. Each test was repeated three times with three replications.

Compatibility testing of antifungal rhizobacterial isola-tes. In vitro antibiosis among the isolates was tested on PDA. In each PDA Petri dish 10 μl of each isolate (grown for 24 h) was spotted and incubated at 28 ±2°C for 96 h. After incubation the growth was scraped from each Petri dish and was exposed to chloroform vapour for 1 h. After evaporation of chloroform, 10 ml soft PDA containing 1 ml of the rhizobacterial isolates (grown for 24 h) were over-layered and incubated for 24 h at 28±2°C. Observation was recorded for clearing zones in the top soft agar.

Preparation of fungal inoculants,Bacillus sp. MR-11(2),Bacillus sp. MRF and Tn5::lacZ mutant (M23) of fluorescent Pseudomonas sp. EM85.Fungal inoculants were raised in 250-ml Erlenmeyer flasks containing sand and maize meal mixed in a 3:1 ratio, i.e. 75 g dry sand and 25 g of maize meal, with 30 ml of water to moisten the mixture. Each flask was sterilised at 121°C for one hour on two consecutive days. Each flask was inoculated with one agar bead containing Macro-phomina phaseolina,Fusarium moniliforme and Fusarium graminearum(from two days growth of the fungi on PDA; beads were taken using Pasteur pipettes) and incubated at 28°C for five to seven days for uni-form mycelial growth. Inoculum of the Tn5::lac Z mutant (M23) of the fluorescent Pseudomonas sp. EM85 was grown in nutrient broth containing kanamy-cin and nalidixic acid at 50 μg ml–1, whereas Bacillus spp. MR-11(2) and MRF were grown in nutrient and PDA broth, respectively. Each broth was centrifuged at

12,000 rpm, washed with phosphate-buffered saline (PBS)three times, and then pellets were dissolved in PBS and the OD was adjusted to 1.2 before using the bacteria for pot experiments.

Isolation,purification and characterisation of anti-fungal compound s from bacterial isolates. Antifungal compounds were isolated from Pseudomonas sp. EM85 by the procedure of Douglas and Gutterson (1986). EM85 was grown on TY Petri dishes and incubated at 28 ±2°C for five days. After five days, the agar was minced and shaken overnight in 80% acetone (v/v) in equal proportion. The acetone fraction was decanted and filtered through Whatman no. 44 filter paper. The liquid volume was reduced by flash evaporation at 55°C and made up to 80% (v/v) with ethanol and incu-bated overnight at 4°C. The pH was adjusted to 4.55. This was then filtered and the volume was reduced and extracted once with methanol:chloroform (1:1, v/v) and then three times with an equal volume of chloroform. The organic phases were combined, evaporated to dry-ness, and dissolved in 5 ml of chloroform-methanol (1:1, v/v). Bioassay was done against R. solani in PDA. Fluorescent pigment was isolated from PDA Petri dis-hes by extracting with water.

The procedure of Homma et al.(1989) was modified to isolate all possible antifungal compounds produced by the two bacilli isolates MRF and MR-11(2). The cul-tures were grown on PDA Petri dishes (300 Nos.) con-taining 20–25 ml solid agar. Petri dishes were incuba-ted at 28°C for 7 days. At the end of incubation, bac-terial growth was scraped, and minced agar was collec-ted in a 5-l flask. It was then extracted with an equal volume of chilled acetone (v/v) and kept overnight. The acetone fraction was collected and extracted twice with diethyl ether (v/v). The diethyl ether fraction was then collected and dried in vacuo.This was then dissolved stepwise in acetonitrile, methanol and acetone. Alternatively, the remaining acetone fraction was extracted twice each with ethylacetate and chloroform (v/v) and dried in vacuo. This was then dissolved in methanol. All fractions were bioassayed against Rhizoctonia solani,Macrophomina phaseolina, Fusarium solani,Fusarium moniliforme and Fusarium graminearum on PDA. Active fractions were main-tained for further purification.

Antifungal compounds were purified as described by Homma et al.(1989). Purification was done on TLC plates (Silica gel GF

254

and Silica gel G

60

, Merck) using different solvent systems, ethyl acetate:methanol (1:1), ethylacetate:methanol:water (1:1:1), methanol:acetone (1:1), and acetone:benzene (1:1). Spots were developed

by I

2

vapour and observed under UV(254 nm). Bioassays on TLC plates were performed against

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Macrophomina phaseolina following the procedure of Homma et al.(1989), as all the bacterial isolates were antagonistic to this pathogen. After purification of the spots in the solvent system, TLC plates were sterilized under UV light for 4 h, then the plates were over-layered with soft PDA containing spores of Macro-phomina phaseolina. Active spots were identified by the lysed zones on the TLC. Active spots were eluted from the preparative TLC plates after optimising the R f values in the previously mentioned solvent systems.The eluted samples were dissolved in the solvent where they were originally dissolved. Purity was checked until a single spot developed. The purified fractions were dried in vacuo,crystallized at low temperature, and stored at 4°C for further studies.

Purified antifungal compounds were analysed by UV-spectrum analysis. UV-spectra were taken with a Hitachi Mode double beam UV-VIS spectrophotometer in methanol and distilled water using a quartz cuvette (1 cm path length). IR analyses were also carried out.In situ biological control assay.Potting mixture was prepared by mixing 100 g of sand-maize meal-grown Macrophomina phaseolina,Fusarium moniliforme and Fusarium graminearum with 900 g sterile soil (clay loam, pH 6.8) in polythene bags and then mixing thoroughly with unsterile soil in 18′′earthen pots con-taining 30 kg soil. The soil was amended with nitrogen (40 kg N ha –1) in the form of urea and phosphorus (60 kg P 2O 5ha –1) in the form of single super phos-phate. Control treatment received only unsterile soil.The fungal inocula were applied five days prior to sowing to facilitate their multiplication. Maize (Zea mays L.) seeds (variety DHM-103) were imbibed for 12 h, and eight seeds pot –1were sown at a depth of 2.5 cm. Six ml of the bacterial inocula in PBS were placed on the surface of each seed after adjusting the O.D. to 1.2 (660 nm) for all cultures. In the treatments receiving two and three biocontrol agents, 3 ml and 2 ml of each culture were applied to the seeds and cove-red with soil. One week after germination, the plant population was thinned to 6 plants pot –1and allowed to grow up to 60 days. The experiment was conducted during the rainy season to ensure that the humidity favoured disease expression. Pots were kept in the open with an average day and night temperature of 30°C and 22°C, respectively. Three separate experiments were conducted with three pathogens. Enough moisture was maintained by watering regularly with 800 ml pot –1.There was a total of 9 treatments in each experiment with eight replications, which included: a) soil control;b) pathogen control; c) pathogen with Tn5::lac Z-tagged mutant (M23) of EM85; d) pathogen with iso-late MRF; e) pathogen with isolate MR-11(2); f) patho-gen with M23 and MRF ; g)pathogen with M23 and

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marker for fluorescent Pseudomonas sp. EM85. Ten g each of the rhizosphere soil, rhizoplane (root surface)and surface-sterilized roots were taken for endorhizo-sphere population. For enumerating the M23 mutant of the EM85 isolate, blue colonies were counted on TY Petri dishes containing antibiotics (μg ml –1): Km 50,Nal 50, Cm 100, and cycloheximide 100together with IPTG (4 μl of 200 mg ml –1stock) and X-Gal (40 μl of 20 mg ml –1stock). F or isolate MRF , appropriate dilutions were plated on PDA Petri dishes containing kanamycin (25 μg ml –1), tetracycline (5 μg ml –1) and cyclohexi-mide (100 μg ml –1). Colonies of MRF were different-iated from other organisms on the basis of the gummy and mucoid colonies it produced on PDA. MR-11(2)was differentiated onto TY Petri dishes on the basis of big, rough, and serrated colonies.

Statistical analyses.Disease severity ratings were ana-lysed according to Dunnett’s test. Percent disease reductions were analysed following Duncan’s multiple range test after arc sin transformations. Population den-sities were analysed according to Duncan’s multiple range tests after log transformations of individual esti-mations. SE of the mean of the inhibition zones produ-ced by the biocontrol agents was also determined.

Results

In vitro antagonism

Fluorescent Pseudomonas sp. EM85 strongly inhibited the fungi, Macrophomina phaseolina,Fusarium moni-

liforme and Fusarium graminearum,both on PDA and NA (Table 2). It produced 8 mm of inhibition zones on PDA against all pathogens, while it could produce 7, 5 and 5mm of inhibition zones on NA against Macro-phomina phaseolina,Fusarium moniliforme and Fusa-rium graminearum,respectively. Bacillus sp. MR-11(2)was the best in exhibiting inhibitory effects against the pathogens, as it produced 15 mm of inhibition zones against all pathogens on PDA, while it produced 12, 10and 15 mm of inhibition zones on NA against Macro-phomina phaseolina,Fusarium moniliforme and Fusa-rium graminearum,respectively (Table 2). Bacillus sp.MRF was also equally potent in inhibiting Macro-phomina phaseolina and Fusarium moniliforme (Fig.1)besides inhibiting Fusarium graminearum in vitro (Table 2). However, the isolate was more efficient on PDA than on NA.

Antifungal traits of the rhizobacterial isolates

The fluorescent Pseudomonas sp. EM85 was found to produce antifungal antibiotics (Afa +), siderophore (Sid +), cyanide (HCN +), and fluorescent pigments (Flu +) (Table 1). The fluorescent pigment produced on PDA was yellow-green and a typical character of this isolate. Production of ammonia, chitinase and antifungal volatiles were not detected. Bacillus sp. MR-11(2) exhibited the production of antifungal anti-biotics (Afa +), siderophore (Sid +) and antifungal volatiles (Afv +). However, isolate MRF produced anti-fungal antibiotics (Afa +) and siderophore (Sid +) only (Table 1).

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Fig.1.In vitro antifungal activity of Bacillus sp. MRF against: left; Macrophomina phaseolina;right; Fusarium moniliforme

Quantification of plant growth promoting traits Fluorescent Pseudomonas sp. EM85 (Km r Nal s Cm r )produced catechol type of siderophore (0.108 mg mg –1protein) and indole acetic acid (3.84 μg ml –1), fixed atmospheric nitrogen (6.76 nmoles C 2H 4h –1tube –1),and solubilized tri-calcium phosphate (14.13 mg 100–1ml broth) besides producing organic acids like gluco-nic, citric, succinic, and α-ketobutyric acid (Table 1).Bacillus sp. MR-11(2) (Ap r ) produced only catechol type of siderophore (0.092 mg mg –1protein). Bacil-lus sp. MRF (Km r Tet r ) produced indole acetic acid (3.71 μg ml –1), fixed atmospheric nitrogen (33.57 nmo-les C 2H 4h –1tube –1), and solubilized tri-calcium phos-phate (25.70 mg 100–1ml broth) besides producing organic acids like gluconic, citric, tartaric and α-keto-butyric acid (Table 1).

Isolation and phenotypic characterisation of Tn5::lacZ insertion mutants of isolate EM85

Transposon mutagenesis was carried out to insert the lac Z gene into the chromosome of the fluorescent Pseudomonas sp. EM85 for studying the ecological competence of the isolate after its introduction into the maize rhizosphere. A total of 160 mutants were obtained and characterized for studying the deficiencies or overproduction of the antifungal traits. Only few isolates produced deficiencies or overproduction of antifungal traits against the pathogens. One mutant,M23, was taken for the experiment to monitor the population dynamics of the isolate in the maize rhizo-sphere. The mutation did not affect the ability of the mutant M23 to inhibit Macrophomina phaseolina,Fusarium moniliforme and Fusarium graminearum in vitro (Table 2). Mutagenesis did not affect the produc-tion of HCN, antifungal antibiotics, fluorescent pig-ment(s) and siderophore as compared to wild type (Table 1).

In situ suppression of charcoal rot of maize caused by Macrophomina phaseolina

Treatment with Macrophomina phaseolina caused char-coal rot in maize. Typical symptoms of charcoal rot were noticed in treatments with the pathogen (Fig.2).Three antagonistic rhizobacterial isolates were evalua-ted for their performances to control charcoal rot.Instead of the wild-type isolate of fluorescent Pseudomonas sp. EM85, its Tn5::lac Z mutant was taken together with two bacilli isolates, MR-11(2) and MRF, alone or in combinations. Treatments with anti-fungal rhizobacterial isolates significantly (P = 0.05)reduced the disease severity compared to pathogen con-trol (Table 3). However, combination of the two bacilli

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isolates MRF and MR-11(2) produced the best result and reduced the disease severity from 2.98 in pathogen control to 0.93 when treated with these two isolates (Table 3). All isolates were efficient in reducing disease intensity. When inoculated alone, Bacillus sp. MRF was the most efficient in reducing disease severity, while combinations of all three isolates produced the same disease intensity (Table 3). While isolate MRF could reduce the Macrophomina -induced disease by 53.55%,M23 and MR-11(2) alone reduced the disease by 49.08% and 35.43%, respectively (Table 3). There was no significant difference among the treatments except for treatments with Bacillus sp. MR-11(2).Combination of MRF and MR-11(2) was synergistic and slightly more efficient in disease reduction (56.04%) than the combined application of all three antifungal isolates (52.42%). Inoculation of the

rhizobacterial isolates significantly increased plant bio-mass and height at 60 days after seeding (unpublished data).

In situ suppression of maize d iseases caused by Fusarium moniliforme and Fusarium graminearum Fusarium graminearum caused both, root rot and collar rot (Fig.2) and wilting of maize plants after inoculation.Treatments with all antagonistic plant growth promot-ing rhizobacterial isolates, a mutant of EM85 (M23),MR-11(2) and MRF, either alone or in combinations reduced the root rot disease severity significantly (P = 0.05) compared to pathogen treatment (Table 4).However, there was no significant difference among the treatments inoculated with the rhizobacterial isolates either alone or in combinations in reducing the root rot

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Fig.2.In situ expression of maize diseases and their biological suppression. 1; collar rot by Fusarium graminearum;2; foot rots/collar rots by Fusarium moniliforme in only one plant and all other healthy plants due to inoculation of a Tn5::lac Z mutant (M23) of fluorescent Pseudomonas EM85; 3; charcoal rot by Macrophomina phaseolina;unmarked; left: healthy root due to seed treatment with M23 mutant; right: rotten root caused by Fusarium moniliforme in the pathogen control treatment.

of maize. The best result was obtained with a combina-tion of a Tn5::lac Z mutant of fluorescent Pseudomonas sp. EM85 (M23) and Bacillus sp. MRF, which reduced root disease severity from 2.23 in the pathogen control to 0.41 (Table 4). When treated alone, Bacillus sp. MRF produced the best result in reducing the root rots di-sease severity. Co-inoculation of Bacillus sp. MRF and Tn5::lac Z mutant (M23) reduced the root rots disease (64.60%) significantly (P=0.05) compared to the treatments inoculated with MR-11(2), combination of MRF and MR-11(2) and all the three (Table4). There was no significant difference among all other treat-ments in terms of percent disease reduction to that of the co-inoculation of MRF and M23, and this was found consistent with the results obtained with root rot disease severity ratings.

Fusarium graminearum also caused severe collar rots (Fig.2) and wilting of maize plants at 60 days after seeding. Evaluation of disease severity ratings revealed the least collar rot and wilting incidence when co-inoculation with the two bacilli isolates MRF and MR-11(2) was performed (Table4). Combined application of all three biocontrol rhizobacteria was not efficient. However, significantly (P= 0.05) reduced disease se-verity ratings were obtained with all treatments com-pared to pathogen inoculation (Table4). In terms of per-cent disease reduction too, significantly higher disease reduction (58.44%) was achieved with co-inoculation of the two bacilli as compared to all other inoculated treatments except the treatment with MRF and M23, which was equally efficient (Table4). Combined inocu-lation of all biocontrol agents was not efficient in redu-cing the incidence of collar rot of maize (Table4). Like the two other pathogens, root rots (Fig.2) and foot rots and wilting diseases of maize were observed when inoculated with Fusarium moniliforme.Treat-ments with the biocontrol rhizobacteria, either alone or in combinations, significantly (P= 0.05) reduced the mean disease ratings of root rot of maize compared to pathogen (Fusarium moniliforme)control (Table4). The best result was obtained with co-inoculation of MRF and M23 (Table4). Seed treatment with MR-11(2) reduced the disease equally well as dual inocula-tion with MRF and M23. Evaluation of disease reduc-tion revealed that dual inoculation with MRF and M23 significantly (P=0.05) reduced the root rots disease (68.44%) as compared to other treatments except for single inoculation with MR-11(2). Analyses indicated that isolate MR-11(2) reduced the Fusarium monili-forme-induced diseases of maize as well as combined inoculation with MRF and M23 mutant of fluorescent Pseudomonas sp. EM85 (Table4). Healthy root devel-opment was noticed when inoculated with the M23 mutant of the isolate EM85 (Fig.2).

All isolates were found to suppress the Fusarium moniliforme-induced foot rots and wilting disease of maize significantly (Table4). Combined inoculation with the three isolates MR-11(2), MRF and M23 was

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also found to suppress the disease equally well as indi-vidual inoculation with the isolates. However, co-inoculation of MRF and M23 was the best in reducing the disease severity of foot rots and wilting, which was consistent with the result obtained with root rots sup-pression (Table4). While co-inoculation of MRF and M23 reduced the disease by 61.82%, individual inocu-lation of MRF and M23 reduced the disease by 59.34% and 57.48%, respectively (Table4). Percent disease reduction was significantly (P= 0.05) less in case of the combined inoculation of the two bacilli as compared to co-inoculation with MRF and M23.

Overall, analyses of the results revealed that co-inoculation of Bacillus sp. MRF and a Tn5::lac Z mutant of fluorescent Pseudomonas sp. EM85 (M23) was the best in suppressing the Fusarium-induced dise-ases of maize.

Monitoring of the biocontrol inoculants for ecological competence in the maize rhizotic zones

The ability of the biocontrol rhizobacterial isolates to colonise successfully the rhizotic zones of maize, while antagonising the maize pathogens, were evaluated at 30 and at 60 days after seeding and expressed as log no. of cells g–1soil or root. Tn5::lac Z molecular marker was used for monitoring the fluorescent Pseudomonas sp. EM85 while intrinsic antibiotic resistance patterns were used for studying the population densities of the two bacilli, MR-11(2) and MRF.

Pseudomonas sp. EM85, M23, was monitored in the maize rhizotic zones. Results (Table5) indicated that the organism, which was originally isolated from the rhizosphere of maize, was highly efficient in colonizing the root zones of maize at 30 and 60 days after seeding. In the rhizosphere, population densities of M23 were 5.54, 6.42, 5.54 and 5.85 log no. of cells g–1in control and in presence of pathogens, F. moniliforme,F. grami-nearum and Macrophomina phaseolina,respectively (Table5). However, rhizosphere colonization in the presence of Fusarium moniliforme was significantly higher compared to all other treatments at 30 days after seeding. Population dynamics at 60 days after seeding indicated that there was a minor improvement in popu-lation density of M23 except in the presence of F. moni-liforme where the population of M23 was reduced as compared to the population at 30 days after seeding (Table5). There was no significant difference (P= 0.05) among the treatments in population densities of M23 at 60 days after seeding (Table5). In the rhizoplane, popu-lation of M23 was more than 6 log no. of cells g–1in all the treatments at both time points (Table5). At 30 days after seeding, M23 gave a significantly higher popula-tion of 6.58 in the presence of F. graminearum while at 60 days after seeding, it could produce a significantly higher population in the absence of the pathogen (Table5). The organism was also highly efficient in colonizing the endorhizosphere of maize at both time points.

The population densities of the two bacilli isolates, MRF and MR-11(2), were also monitored in the rhizo-tic zones of maize using intrinsic antibiotic resistance patterns both at 30 and 60 days after seeding. Evalua-tion of population densities revealed that Bacillus sp. MR-11(2) was the best colonizer among the three anta-gonistic rhizobacterial isolates in the rhizosphere as

218Microbiol. Res. 156(2001) 3

well as in the rhizoplane. At 30 days after seeding, MR-11(2) could build up population densities over 6.0 log units, both in the rhizosphere as well as in the rhizo-plane (Table5). Similar observations were noticed in the rhizosphere and rhizoplane when population den-sity was evaluated at 60 days after seeding (Table5). Even a higher population density of over 7.0 log no. of cells g–1was observed in all treatments with MR-11(2) in the rhizoplane at 60 days after seeding (Table5). At both time points a significantly higher population of MR-11(2) was obtained in the treatment with Macrophomina phaseolina in the rhizosphere and in the control treatment in the rhizoplane (Table5). Results indicated that Bacillus sp. MR-11(2) was also a colon-izer to the inside of the root. There was no significant difference (P=0.05) in population densities of the isolate MR-11(2) in the endorhizosphere of maize (Table5).

Bacillus sp. MRF was also efficient in colonizing the maize rhizosphere, rhizoplane and endorhizosphere. Population densities in the rhizosphere was not en-couraging as evident from low population densities in the rhizosphere as compared to the population in the rhizoplane (Table5). While it could build up a popula-tion density of 4.90 log no. of cells g–1in the rhizo-sphere at 30 days after seeding, it gave 6.93 log no. of cells g–1in the rhizoplane at 60 days after seeding (Table5). It could also colonise the inside of maize roots.

Isolation,purification and characterization of the antifungal compounds from the rhizobacterial isolates and bioassays

In addition to the production of antifungal antibiotic and fluorescent pigment (as reported earlier by Pal et al. (2000), the fluorescent Pseudomonas sp. EM85 was also found to produce two more antifungal compounds active against maize root pathogens besides inhibiting Rhizoctonia solani(Table6). Both compounds were isolated and purified. The third compound produced by this biocontrol agent was soluble in methanol with UV

Microbiol. Res. 156(2001) 3219

absorption of 225.5 nm (λmax ) and an R f of 0.42 (metha-nol:acetone, 1:1 solvent system) and 0.56 (metha-nol:ethyl acetate, 1:1 solvent system). Another water-soluble compound was purified from this isolate with UV absorption of 209 nm (λmax ) and R f of 0.70(Benzene:water, 1:1 solvent system). During bioassay,these two purified compounds strongly inhibited Rhizoctonia solani besides inhibiting Macrophomina phaseolina (Table 6). The chemical nature and structu-res of these unique compounds are under investigation.Only one antifungal compound was isolated from Bacillus sp. MR-11(2), soluble in methanol, with UV absorption of 236.5 nm (λmax ) and an R f of 0.22 (ethyl-acetate:methanol, 1:1 solvent system). The compound

was viscous in nature and was found strongly inhibitory against R. solani,Fusarium solani,Macrophomina phaseolina (Figs.3 and 4), Fusarium moniliforme and Fusarium graminearum (Table 6).

Similarly, three potent antifungal compounds were isolated and purified from Bacillus sp. MRF. One of these compounds was found to be soluble in methanol with UV absorption of 229.5 nm (λmax ), viscous and an R f of 0.65 (ethylacetate:methanol, 1:1 solvent system).The compound strongly inhibited Rhizoctonia solani,Fusarium moniliforme and Macrophomina phaseolina (Fig.3 and 4) in in vitro and TLC bioassays (Table 6).Similarly, a water-soluble and solid antifungal com-pound with a molecular weight of 355, R f of 0.10 (ethy-lacetate:methanol:water, 1:1:1 solvent system) and UV absorption of 212.5 nm (λmax ) was also isolated (Table 6). This purified compound strongly inhibited Rhizoctonia solani,Fusarium moniliforme and Macrophomina phaseolina (Fig.3, 4) in vitro and TLC bioassays (Table 6). The third compound was soluble in acetone and acetonitrile with an R f of 0.42(acetone:benzene, 1:1 solvent system) and UV absorp-tion of 351.0 nm (λmax ). The compound was viscous and strongly inhibited R. solani, F. moniliforme and Macrophomina phaseolina (Table 6).

Discussion

Despite several reports on the degree of suppression of maize root diseases caused by Fusarium graminearum,Fusarium moniliforme and Macrophomina phaseolina,by different rhizobacteria like Bacillus spp.(Kommendal and Chang 1975), Pseud omonas fluor-

220

Microbiol. Res. 156

(2001) 3

Fig.3.In vitro inhibition of Macrophomina phaseolina by a purified compound of: left Bacillus sp. MR-11(2); right: water soluble compound of Bacillus sp. MRF. 25 μl of the purified active compound was spotted at the center of the PDA

Petri dish.

Fig.4.TLC bioassay of the antifungal compounds active against Macrophomina phaseolina.F rom left to right:Compound of Bacillus sp. MR-11(2), water-soluble com-pound of Bacillus sp. MRF, methanol-soluble compound of Bacillus sp. MRF.

escens(Raju et al.1999), Pseudomonas spp. (Chen et al.1999), Pseud omonas cepacea(Hebbar et al. 1992a, b) and Burkholderia cepacea UPR5c (Sanchez et al.1994), no studies on the biocontrol of these maize root pathogens with a fluorescent Pseudomonas sp. EM85 (which could produce fluorescent pigment in PDA along with nitrogen fixation, phosphate solubili-zation and organic acid producing attributes) have been performed together with other plant growth promoting bacilli.

All three rhizobacterial isolates taken for the disease suppression experiments were obtained from maize rhizosphere and endorhizosphere, which represented the predominant groups of maize rhizosphere and endo-rhizosphere populations. Soil pseudomonads and bacil-li were found frequently within the root tissues in maize (Hebbar et al.1992a). Moreover, the antagonistic endo-rhizosphere population is more important for success-ful colonization of the biocontrol agents for effective competition against the root invading maize pathogens (Lalande et al.1989).

All rhizobacterial isolates exhibited strong antifungal activities against maize root pathogens (Table2). However, inhibitory effects were more prominent on PDA than on NA. The nutrient constituent of the medium plays a significant role in influencing the pro-duction of a particular antifungal metabolite (Hebbar et al.1992b) by the antagonistic rhizobacteria. The dif-ferences in the inhibitory effect on the fungal pathogens might be due to the nutritional differences of the two media. Similar observations were also reported earlier with Pseudomonas cepacea(Hebbar et al.1992a). Fluorescent Pseudomonas sp. EM85 also fixed atmospheric nitrogen, solubilized tri-calcium phos-phate, produced catechol type of siderophore, IAA and organic acids. All these plant growth-promoting attri-butes might have contributed to enhancing plant bio-mass, healthy root and plant growth. Similar obser-vations were also recorded with the two bacilli isolates. Plant growth promotion by pseudomonads and bacilli are well documented and found to influence the plant to develop resistance against the root invading pathogens by production of organic acids (Glick 1995).

Little correlation was observed between in vitro anta-gonism and in situ disease suppression in several studies (Hebbar et al.1992a). The fluorescent Pseudo-monas sp. EM85 exhibited antifungal traits such as pro-duction of siderophore, HCN, antibiotics and fluores-cent pigment. The fluorescent pigment produced on PDA was different from the siderophores produced on CAS agar (Pal et al.2000). While Bacillus sp. MRF produced antifungal antibiotics and siderophore, MR-11 (2) produced antibiotic, volatiles and siderophores as antifungal traits. The possible mechanisms by which fluorescent Pseudomonas and bacilli exhibit biocontrol have been reported (Weller 1988; V oisard et al.1989; Bull et al.1991; Dowling and O’Gara 1994; Cartwright et al.1995; Emmert and Handelsman 1999). Application of the compatible plant growth pro-moting rhizobacteria either singly or in combinations effectively suppressed the disease severity and increas-ed the percent disease reduction caused by Macro-phomina phaseolina,Fusarium moniliforme,and Fusarium graminearum, although there was not much variation among the treatments.

A large number of soil microorganisms are capable of producing siderophores. While bacterial sideropho-res are of both catechol and hydroxamate types, fungal pathogens usually produce hydroxamate siderophores. As fusaria are reported to produce siderophores of their own, involvement of bacterial siderophores in suppres-sing these maize pathogens may be ruled out. Similar observations were also made with Pseudomonas cepa-cea antagonistic to Fusarium moniliforme and in other studies (Hebbar et al.1992b; Neiland 1986). Moreover, siderophores may not be produced in sufficient quan-tities in the soil microcosm to have any significant bio-control effect (Misaghi et al.1988).

Availability of sufficient iron in initial stages of plant growth may have hindered the production of sidero-phores. Similarly, insufficient amounts of cyanogenic glucosides in the root exudates at early stages of plant growth could have prevented cyanide production. Moreover, cyanide is rapidly inactivated by soil col-loids (V oisard et al.1989). Thus, cyanide production might not contribute to suppression of maize root pathogens.

It has been shown in several studies, that sideropho-res have little or no role in disease suppression (Hamdan et al.1991), while antibiotics, antifungal volatiles and other metabolites are involved in suppres-sion of Fusarium moniliforme,Fusarium graminearum and Macrophomina phaseolina(Hebbar et al.1992a). Hence, antifungal antibiotics and fluorescent pigments produced by the fluorescent Pseudomonas sp. EM85, which were also found to be involved in controlling R. solani in cotton (Pal et al.2000), antibiotics and anti-fungal volatiles produced by Bacillus sp. MR-11(2) and antifungal antibiotics of Bacillus sp. MRF might be involved in the biological suppression of these maize root pathogens. Involvement of non-siderophore fluorescent pigment in the suppression of maize root pathogens is unique. However, development and evalu-ation of deficient mutants of the different antifungal traits of these rhizobacteria and their analyses could unravel the specific traits involved in the biological suppression of the maize root pathogens. Work has been initiated in this direction in our laboratory.

Bowen (1978) suggested that high soil populations coupled with faster growth rates and high levels of

Microbiol. Res. 156(2001) 3221

competitive abilities were the key for effective biocon-trol agents. Successful colonization of the biocontrol agents is a pre-requisite for exerting any biocontrol effects (Hebbar et al.1992a; Dowling and O’Gara 1994). In the in situ disease suppression experiments, it was observed that all antifungal rhizobacterial isolates could colonize successfully the inside of the root tis-sues. Evaluation of population dynamics of all three biocontrol agents using either lac Z molecular or intrin-sic antibiotic markers revealed the proper colonization of the isolates. This is important because pathogens need to invade the root tissues for disease expression. There was a significant population of the inoculant strains on the root surface too (estimated on the basis of molecular marker and antibiotic resistance markers, Table5). Again, the generation time of the biocontrol agents was low enough to facilitate early establishment of the inoculant strains. This in turns facilitated the organisms to establish in the root tissues before the pathogens could invade. Thus, niche exclusion could have been involved in minimizing the incidence of maize root diseases. Similar observation were recorded in several earlier studies (Hebbar et al.1992a; Dowling and O’Gara 1994; Weller 1988). However, only in very few occasions, inoculants strains were recovered from the roots and rhizosphere by using molecular markers. Moreover, one antifungal compound produced by Bacillus sp. MRF was soluble in water. This is im-portant as it would have allowed the metabolite to travel to the entire root zones to exert suppression of the sensitive pathogens. The involvement of the antifungal metabolites in suppression of maize root diseases is further substantiated by the fact that all purified meta-bolites exhibited strong inhibitory effects against the pathogens in TLC as well as in Petri dish bioassays. Although significant variation in disease suppression was not evident when inoculated in combinations, the combination could provide better ecological competi-tion with the pathogens than the individual one, and fail-ure of one organism may be complemented by others. The best combination among the three was found to be Bacillus sp. MRF and fluorescent Pseudomonas sp. EM85.

Thus, we conclude that combinations of fluorescent pseudomonas and bacilli could suppress the maize root invading pathogens efficiently. F luorescent pigment and antifungal antibiotics (or metabolites) of Pseudo-monas sp. EM85 and antifungal antibiotics of both bacilli coupled with successful root colonization of the biocontrol agents might be involved in biological suppression of the pathogens. To the best of our knowl-edge, this is the first report showing the involvement of non-siderophore fluorescent pigment of fluorescent Pseudomonas in biological suppression of maize root pathogens.Acknowledgements

The work was supported by a Senior Research Fellowship of the Indian Agricultural Research Institute, New Delhi-110012, India. Authors are thankful to Dr. P. Dureja for helping in spectral analyses, T. Dasgupta for photography, and Amrit Pal for helping in statistical analyses. References

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手机root权限获取的2种通用方法,开启搞机的第一步

手机root权限获取的2种通用方法，开启搞机的第一步 对于搞机达人来说，获取Root权限是开启搞机道路的第一步。那么对于刚刚接触搞机的同学来说，对于获取Root权限这个过程还是有点心慌，毕竟弄不好可能分分钟变假砖。所以我们今天通过这篇文章，跟大家简单的介绍一下有哪些方法可以获取手机Root权限。 一、卡刷获取 说到卡刷，很多朋友就是有印象了。卡刷刷机包，通过第三方工程模式可以进行刷机。所以我们第一个要介绍的就是通过第三方的Recovery来刷入Root权限。已经有第三方Recovery的同学直接看看第四步。

1.材料准备:手机、电脑、数据线、ADB工具、Recovery包，Root卡刷包。 2.为Recovery取一个名字，之后复制这个名字。 3.打开ADB工具、将Recovery包放入ADB工具。 4.将root卡刷包放入手机中。关机，进入fastboot界面，手机连接电脑，在电脑ADB 工具窗口中输入fastboot flash recovery. 然后Ctrl+V粘贴Recovery包的名字，最后输入.img。心细的朋友直接fastboot flash recovery.文件名.img就可以了。之后按回车键。 5.刷入之后手机将会重启，之后关机。同时按住音量下以及电源键，待震动后放手进入Recovery模式。

6.选择Install或者安装，在路径中找到Rotor卡刷包。刷入重启即可。无需双清。

二、通过Root工具获取

1.准备材料：手机、电脑、数据线、强力一键Root软件。 2.电脑端安装强力一键Root。 3.手机进入设置，关于手机，连续按版本号，知道开启开发者选项。

酷派7260获取ROOT权限操作方法

纯ROOT步骤 1 打开手机USB调试模式【进入设置-应用程序-开发，然后把USB调试模式打钩，手机驱动要必须装好，才能进行刷机，】 2 安装驱动，把

手机插入电脑，弹出安装驱动菜单，点击，找到PC_Driver 文件夹的驱动，安装。在刷机包里. 3 官方升级包官网032下载的：https://www.sodocs.net/doc/eb5807065.html,/file/dp75blgd# :官网031 下载地：https://www.sodocs.net/doc/eb5807065.html,/file/e7orghdm# ：官网027下载地：：https://www.sodocs.net/doc/eb5807065.html,/c0hmrozkgb：任意下载一个官网刷机都行。 4 手机断开电脑，把所有卡取下，（有人说不用） 5 不连接手机，打开“组装客服Downloader.exe”，点开始。此时上面“boot”、“system”、“userdata”、“coolpad”四个选项可经行操作，只选择boot.

6 首先下载Root所需的2个文件https://www.sodocs.net/doc/eb5807065.html,/file/dpx9yx32和https://www.sodocs.net/doc/eb5807065.html,/file/anhahuqr#boot-ROOT+RE.img，将“组装客服Downloader-boot+recovery.ini”改名为“组装客服Downloader.ini”，复制到download_V9.01.27目录下覆 盖原文件。将“boot-ROOT+RE.img”改名为“boot.img”，复制到TSNCJOLY目录下覆盖原文件。

7 手机7260关机，按住音量上的同时将手机连接USB数据线到电脑，手机界面提示“通讯中”，升级工具提示“联机”，点『开始』按钮，开始刷机，等待直到手机重启完成即可，几秒钟！ 8 进入系统后可以看到Superuser已经安装，验证一下是否Root，酷派7260获取Root权限就完成了。用re管理器删除你不要的软件吧！就这么简单！

电脑安卓手机游戏模拟器哪个好用 第三方评测对比

电脑安卓手机游戏模拟器哪个好用第三方评测对比 使用手游助手模拟器可以直接在电脑上玩手游，效果比手机上更好。在使用手游助手安卓模拟器的时候最好的方法就是具体地进行测试，但是不可能真的就将目前市场上所有的产品都尝试一遍，那样花费的时间和精力将非常的可怕。这篇说明的初衷就是解决用户的需求。 梳理了一遍模拟器，筛选掉那些没有自主实力的非自研安卓模拟器之后，对目前最常用的模拟器进行测评，并将结果公布出来，希望可以给更多的人来选择适合自己的安卓模拟器产品。我们挑选了逍遥安卓模拟器、Bluestacks、天天模拟器、靠谱助手、海马玩和夜神模拟器进行使用。 一、安卓模拟器的启动速度快慢是直接影响用户使用体验的根本 安卓模拟器的启动速度快慢是直接影响用户使用体验的根本，没有人能够忍受长达几十秒的启动时间，速度就是效率，就是安卓模拟器对用户体验最好的优化。逍遥安卓模拟由于是纯净模式速度最快，而海马玩由于弹出大量的广告速度慢体验差，Bluestacks和靠谱是一个内核，由于技术的局限性，优化效果一般。 二、性能跑分是安卓模拟器的强弱直接体验 软件产品好不好，看第三方跑分就行，跑分的高低直接决定了安卓模拟器性能的强弱。

三、技术决定了安卓模拟器使用门槛的高低 安卓模拟器的技术非常复杂，因为技术的强弱决定了的内核技术的优化，也决定了使用者的门槛。逍遥安卓模拟器在这方便是天生的优势，研发团队是全球虚拟化领域的专家，技术实力的差距不是靠人数就可以平衡的，因此逍遥安卓模拟器的内核比其他安卓模拟器都要稳定！ 四、安卓模拟器的兼容性决定了使用价值 安卓模拟器的兼容性是由安卓模拟器内核的优化影响的，兼容性的好坏对于用户有直接的影响。用户会经常性安装软件，兼容性差的安卓模拟器会导致系统奔溃或者不兼容。

手机ROOT是指什么,如何获取root权限

手机ROOT是指什么，如何获取root权限 众所周知,现在国内所有的安卓手机都是定制版的，想要打造专属的个性手机，就必须进行root，于是乎，大家纷纷加入root阵营，但你真的确定你懂root。 一、root是什么 root其实就是手机系统的超级管理员。root后就可以摆脱商家的限制，取得手机的绝对掌控权。说白点，就是你不仅可以删掉看不顺眼的预装软件，甚至能把整个手机系统都换了。很牛掰有木有。那具体要怎么做呢？ 二、如何获取root权限 现在，为了阻止大家root手机，各厂商也是伤透了脑筋，对root的限制也越来越严格。 下面我们来列举几个手机品牌的root 1、华为

华为手机要解锁后才能root。 首先，在华为官网中选择解锁，并签署解锁协议。 然后填写相关的产品信息后，在手机上输入*#*#1357946#*#*，即可获得产品识别码，提交后就能获得解锁码。 2、魅族 魅族手机root需通过品牌特有的flyme账号，通过账号进入个人中心，然后点击“开放系统权限”，但是，需要特别注意的是：魅族手机root后就失去保修资格了。

3、oppo oppo手机作为后起之秀，也赢得了一批忠粉，但是其要取得root权限是相当的麻烦。 首先，手机设置成recovery模式 操作：将手机关机，然后同时按住“音量下键”和“电源键”，直到出现开机LOGO，先松开电源按键，“音量键”不放，几秒后，即可进入Recovery模式。

进入Recovery模式后，Recovery模式下使用音量键移动，电源键确认，对手机进行清空数据和缓存操作，最后重启手机，将手机恢复出厂设置。 4、小米 与oppo相比，小米的就非常的人性化。在手机自带的“安全中心”选择“授权管理”，然后点击“root权限管理”即可。

小米稳定版的root权限获取

小米稳定版root权限的获取 小米稳定版自从CS 21.0后MIUI开发小组出于系统稳定的考虑取消了root权限的授权，对我们发烧而生，却又没什么时间折腾的米粉来说很是纠结啊！稳定版要是可以root 权限就好了！其实稳定版也是可以很简单获得root权限的，root权限在之前的小米稳定版里一直是有这样一个图标“授权管理”来管理的，现在的稳定版也有，只是不再提供root权限的授予了，所以归根到底我个人认为root权限这个授权管理对于整个小米MIUI系统来说也是一个应用，只是现在这个应用的部分功能被限制了就是root权限的授予，但是之前的版本里这个应用的所有功能是开放的，受高人的指点，我在之前版本里成功的提取了有全部功能的“授权管理”这个应用。 具体的步骤： 1，将授权管理APK安装包拖到内存卡里，记下路径，方便一会儿通过文件管理找到安装。（个人建议直接放在根目录下） 2，通过小米手机自带的文件管理找到刚刚存在内存卡里的授权管理安装包，安装替换原来的“授权管理”（没有root授权的）应用。安装成功后点右下角的“完成”不要点左下角的“打开” 成功后重启手机，找到授权管理这个应用，打开在软件权限管理里打开所有的监控，如下图。 为了保险起见，大家再重启下手机，应该在开机以后360手机卫士，或者手机毒霸之类的会请求root权限，这时候你就可以看到提示要不要授予这些软件最高权限，并且可以授予它们最高权限了，说明我们成功了！ 注： 在获得root权限后，还是会显示（下图）稳定版没有root权限，这个属于UI界面（我也是业余的不知道是不是这样个情况，还希望高手专业指点，谢谢）的显示把这个我能力有限无法修改，不过不耽误我们用嘿嘿！

自定义ROM及手动获取ROOT权限完整教程

自定义ROM及手动获取ROOT权限 完整教程 内心强大者无所畏惧BY 郑明宇 不知道大家有没有一个习惯，当拿到一个新的安卓手机时，第一个想法，就是上网搜索有没有Root方法，如果有，内心一阵喜悦。但是，在安卓手机更新越来越快，新机型不断出现的情况下，想找一个适合自己手机的Root方法并不是那么容易。SO，那我们就自己来动手吧！————————————分—————割———————线———————————— 索引 本教程基于刷机小强——天语T580，联想A278t通用。 本教程主要完成以下任务： 1、在原厂ROM的基础上，手动获取ROOT权限。 2、修改U-BOOT，调整DATA，SYSTEM，CACHE等各分区大小。 3、修改System.img，添加软件，修改字体，制作专属于自己的ROM。 本教程不包含以下内容 1、自定义Recovery（复杂，容易变砖）。 2、系统美化（本人只追求速度，对美化无感）。 3、SD卡分区（本人不喜欢分区）。 材料准备 1、官方ROM包 2、权限管理软件（APK格式，非一键Root软件，是Root之后用来管理权限的软件。网上很多） 3、SU文件。已分享。 工具准备 1、PAC刷机包解包打包+刷机工具：DloaderR V2.93 2、IMG文件修改工具：yaffs2img浏览器破解版 3、U-boot文件修改工具：Winhex 4、解压工具WinRAR

第一部分在原厂ROM的基础上，手动获取ROOT权限 1、获得官方刷机包之后，（文件名类似于960114_8463_V0811.pac）我们需要对PAC文件进行解包，在DloaderR文件夹下，打开Bin文件夹下的DloaderR.exe 2、DloaderR中，点击单齿轮按钮（第一个按钮）打开PAC文件。点击双齿轮按钮（第二个按钮），找到PAC文件临时解包的位置。见图。 吧友补充，可以在运行处输入命令：%temp% 即可进入临时文件夹，推荐此方法，谢谢朋友提醒。

安卓模拟器使用教程

看到网上很多朋友在找怎么在电脑上安装安卓模拟器,安卓模拟器安装方法等.安卓模拟器下载好要进行相对就的操作才可以使用,下面是详细的方法,可以收藏一下! 首先将安卓模拟器下载下来.打开压缩包我们会看到 Java_Runtime_Environment-002d6.1.210.6.exe,及android-sdk-windows文件夹下SDK Setup.exe二个运行程序. Java_Runtime_Environment-002d6.1.210.6.exe为安卓模拟器要配置的JAVA 环境. SDK Setup.exe为安卓模拟器程序.

1.安卓模拟器Java环境安装 运行Java_Runtime_Environment-002d6.1.210.6.exe安装,

完成之后配置环境变量，这个简单，右击计算机，选择属性. 左边的高级系统设置 在系统变量下选择新建 ①JAVA_HOME C:\Program Files\Java\jdk1.6.0_10 ②classpath .;%JAVA_HOME%\lib; ③Path 默认已经有了，找到点编辑，在前面加入这个值 C:\Program Files\Java\jdk1.6.0_10\bin;

安卓模拟器安装包,在android-sdk-windows文件夹下. 2.下载完打开压缩包，运行SDK Setup.exe 自动连接到google的服务器检查可用的包裹 如果你看到一条关于SSL的错误信息，点击Settings标签(在SDK and AVD Manager 窗口左边)。然后把Force https://前面的勾去掉，点确定，然后重新点击 installed packages。

安卓手机Root权限破解

许多机友新购来的Android机器没有破解过Root权限，无法使用一些需要高权限的软件，以及进行一些高权限的操作，其实破解手机Root权限是比较简单及安全的，破解Root权限的原理就是在手机的/system/bin/或/system/xbin/目录下放置一个可执行文件“su”，这是一个二进制文件，相当于电脑上的exe 文件，仅仅在系统中置入这个“su”文件是不会给手机的软件或硬件造成任何故障。 本章讲解使用SuperOneClick这款电脑上的软件来破解系统，因为它相对安全可靠，可破解很多的机型，官方给出支持的机型有：Acer Liquid Metal,Dell Streak,HTC Magic (Sapphire) 32B,HTC Bee,LG Ally,Motorola Atrix4G,Motorola Charm,Motorola Cliq,Motorola Droid,Motorola Flipside,Motorola Flipout,Motorola Milestone,Nexus One,Samsung Captivate,Samsung Galaxy 551 (GT-I5510),Samsung Galaxy Portal/Spica I5700,Samsung Galaxy S 4G,Samsung Galaxy S I9000,Samsung Galaxy S SCH-I500,Samsung Galaxy Tab,Samsung Transform M920,Samsung Vibrant,Sony Ericsson Xperia E51i X8,Sony Ericsson Xperia X10,Sprint Hero,Telus Fascinate,Toshiba Folio 100 准备： 一，如果你使用的是Windows XP的操作系统，首先得在电脑上安装.NET Framework v2.0版或更高版本，不然会无法运行此软件。 微软官方下载地址： https://www.sodocs.net/doc/eb5807065.html,/downloads/zh-cn/details.aspx?FamilyID=0856eacb-4362-4b0d-8edd-aab15c5e04f5二，安装手机驱动，由于Android机型众多，你使用的是什么品牌的手机，就去这个品牌的官方网站上下载相应的套件或驱动安装在你的电脑上，记住是你手机的官方网站，然后找到你的机型再下载，不是百度出来的下载地址。 三，完成前面两步，准备手机数据线，在手机设置>>应用程序>>开发中勾上USB调试 四，下载SuperOneClick，点击这里，然后解压缩（如果多次严格按教程操作无法破解，请点这里下载老版本SuperOneclick进行破解）

如何获取手机root权限

如何获取手机root权限？ 发布时间：2012-09-24 15:08作者：电脑百事网原创来源：https://www.sodocs.net/doc/eb5807065.html,5824 次阅读还在为手机中内置的各种垃圾软件与插件而烦恼吗？让手机Root就可以解决此类烦恼，如今安卓智能手机已经成为国内用户使用最多的智能手机，但不少手机自带的软件与插件用户无法卸载删除，导致不少朋友手机流量浪费比较大，加之自动软件引起了手机速度的，接下来本文将与大家分享如何获取手机root权限，还您干净简洁流畅的手机系统。 这里所说的手机ROOT，就是指帮助用户获得手机最高管理权限，大家会发现很多智能手机内置的软件是无法删除的，这主要是因为手机厂商给我们的权限只是一般的管理员，没有给到最够权限，当然这或许也是处于安全考虑，一旦用户拥有最高权限，可以删除任意手机内部文件，如果操作不当，删除掉了手机内部系统关键文件，则会使手机系统奔溃，不过大家只要多借助一些管理软件这样的情况就可以避免了，废话不多说，下面教大家如何使用z4root软件ROOT 到手机最高管理权限，方法如下： ⒈）首先在手机上下载安装“ z4root软件”，很多手机应用下载网站都有，所有下就找到了，怎么下载与安装这里就不介绍了。下载z4root软件后，我们在手机中安装，之后如下图，点击第一个：Temporary Root（永久获取ROOT权限），如下图：

永久获取ROOT权限 之后即可获取到手机最高ROOT权限，该软件适合于目前绝大多数主流品牌安卓智能手机，要判断手机是否成功获取到了最高ROOT 权限，我们可以通过查看手机内是否有多个“权限管理”来知道，大家再下载一个RE管理器，安装之后就会看到了，如下图：

如何使Android应用程序获得root权限

如何使Android应用程序获得root权限 写这篇文章前，首先要感谢Simon_fu，他的两篇关于root权限的文章对于我的工作起到了非常大的帮助，这篇文章可以说是对他的文章的一个补充。Simon_fu的文章可以参考如下两个网页： Android程序的安全系统 Android应用程序获得root权限 一般来说，Android下的应用程序可以“直接”得到的最大的权限为system，但是如果我们需要在程序中执行某些需要root权限的命令，如ifconfig等，就需要root权限了。按照Simon的文章中提到的，应用程序有以下两种办法临时获得root权限： 1)实现一个init实现一个Service，来帮助Android应用程序执行root权限的命令。 2)实现一个虚拟设备，这个设备帮助Android应用程序执行root权限的命令。 第二种办法我这里没有尝试，暂时也不会。这里讲讲我在实现第一种办法的过程和遇到的一些问题。 1.将我们要执行的命令写成脚本，或者可执行程序。 下面是我的脚本ifconfig_test.sh： #！/system/bin/sh ifconfig 注意：脚本的第一行必须为#！/system/bin/sh，否则无法执行，通过dmesg可以查看到信息内容为cannot execve ./ifconfig_test.sh: Exec format error 也可以采用C/C++编写需要执行的命令或者程序，并在编译image的时候编译成可执行程序。 2.在init.rc中注册service Android中的service需要在init.rc中注册，Init.rc中定义的Service将会被init进程创建，这样将可以获得root权限。当得到相应的通知（通过属性设置）后，init进程会启动该service。 本文中注册的内容如下： service ifconfig_test /system/etc/ifconfig_test.sh oneshot disabled 其中，oneshot表示程序退出后不再重新启动，disabled表示不在系统启动时启动。 注意：这里service name不能超过16个字符。我之前的service name由于定义的比较长，18个字符，设置属性通知service启动后查看dmesg可以看到提示：init: no such service。查看/system/core/init/parser.c的源代码，在parse_service->valid_name函数中可以看到如下内容：if (strlen(name) > 16) { return 0; }，证明service的名字的确不能超过16个字符。 3.将Android应用程序提升为system权限

安卓手机一键root,z4root永久取得最高权限,删除定制软件教程

z4root安卓手机一键root 永久取得最高权限！删除定制软件教程 Root权限是什么？ 1）root是系统中的超级管理员用户帐户,该帐户拥有整个系统至高无上的权力,所有对象他都可以操作，所以很多黑客在入侵系统的时候, 都要把权限提升到root 权限，用windows的方法理解也就是将自己的非法帐户添加到Administrators 用户组。 2）获得root权限之后就意味着已经获得了手机的最高权限，这时候你可以对手机中的任何文件（包括系统文件）执行所有增、删、改、查的操作。 首先下载z4root软件并安装到手机中，安装完成后打开z4root软件。https://www.sodocs.net/doc/eb5807065.html,/anzhuoruanjian/xitonggongju/2011/1216/297.html

root前（建议）：为了让大家更好的完成root，防止意外发生，我们建议备份！备份步骤如下： 1:进入到RE管理器 2:system-app 按下中间的键，全选-复制 3：粘贴到你的sd卡里！ （建议通过数据线再拷贝到电脑上再做个备份，免得sd卡出现问题，备份文件丢失，问题就大了！） Z4ROOT来自XDA的RyanZA发布的，功能非常强大。如果你ROOT失败，也不用担心机器会坏，重启机器就会恢复以前状态。 下面正式开始root，注意了哦！ root教程： 1：开启--usb调试在手机按MENU键点通知点USB已连接点打开大容量存储（勾选） 2：运行z4root

主界面上面有三个选项： Tenmporary Root：取得临时权限 Permanent Root ：取得永久权限 Un-root ：清除root文件 这里我们选择Permanent Root取得永久权限等待几分钟

获取安卓系统最高根权限：root,很简单!

获取安卓系统最高根权限：root，很简单！ 所谓的“root”就是取得操作系统的最高操作权限，就好比windows的管理员权限一样，之所以叫root，是因为安卓系统是以linux为基础进行开发的，linux里的根权限就是root，root的中文意思就是根（根源），也就是最高权限！有一些程序是需要最高权限才能安装或运行的！ 论坛上的那些人，都喜欢装B，就是不肯说白了，偏要学台湾人夹带英文说什么root，让本就不太懂的人更是如坠雾里！ 我也是昨天才开始接触安卓的，昨天刚入手一台x10i,因为对安卓一窃不通才上网到处找资料，昨天看了本论坛的另一贴“[Root权限/提取] 2月19新版superoneclick,亲测10秒内ROOT(435)!”，我马上下载相关软件来操作，一次成功！不知难在哪里！要说难，就是论坛上装B之人太多，不但不直说，反而来给你绕圈子！ 具体操作： 1.首先下载并在电脑上安装Sony_Ericsson_PC_Companion_ 2.01.149，【下载地址：https://www.sodocs.net/doc/eb5807065.html,/software/13200.html】（注：安装这个东西，在这里的作用，我想大概主要是提供了手机的驱动吧，因此，安装好了，用USB把手机连一下电脑，让电脑自行识别并安装USB驱动，安装完了，把USB线断开） 2.然后下载SuperOneClickFor2.1并解压，【下载地址：本论坛另一贴中有https://www.sodocs.net/doc/eb5807065.html,/android-715374-1-1.html】 3.再在手机上先设置USB为调试模式，在“设置--应用程序设置--开发”里面设置！ 4.然后用USB线连上电脑， 5.在电脑上运行SuperOneClick，点击“ROOT”按纽，几秒钟后就完成，OK 完成后，在手机里会多出个“授权管理”的图标来！

一键获取root权限

以下是阿里云出厂时的云OS root工具和教程： 现在已经使用android 2.2的root工具root成功！无需像网友说的那样，开启USB调式模式什么的，谁还说它不是android ？？ 1、下载并安装授权管理工具：Superuser 2、下载并安装root工具：Universal Androot v1.6.1 安装完成后运行Universal Androot v1.6.1，点击Go Root 按钮，即可轻松获取到root权限。 附件中已经包括上面2个软件，下载解压复制到SD卡，安装即可。 一键ROOT工具.zip (426.88 KB) 下载次数: 7841 说明：root工具会被报病毒，这正常的。下载时先把杀毒软件禁用。 3、Root完成之后你就可以用R.E管理器删除system/app下面自己不需要的应用程序了！ R.E管理器下载：https://www.sodocs.net/doc/eb5807065.html,/viewthread.php?tid=30959 初级小白请看下面手把手教你获取root权限（有经验的请路过） 先把那2个工具（可以到https://www.sodocs.net/doc/eb5807065.html,/file/aqx9qpyd#Download 一鍵獲取root權限.rar下载），下载到电脑上。 1、把手机连接电脑，会提示“连接类型选择”，你选择U盘模式，确定！ 2、电脑上会多出一个磁盘，然后把2个文件拷到主目录下。然后断开与电脑的连接。 3、在手机上找到“ Polaris阅读器” 打开，并进入我的文件夹 4、然后找到刚才放入的APK文件，先点击Superuser_2.3.6.2.apk，它会弹出安装界面，再点安装，程序已安装后，点完成 按上面方式，继续安装另一个UniversalAndroot_v1.6.1.apk 5、全部安装完成后，在点方框 ,返回到主桌面上。找到Universal Androot v1.6.1，点击运行！软件打开后，点击Go Root 按

安卓手机root权限获取 一键root软件使用教程

安卓手机root权限获取一键root软件使用教程 今天小曹来跟网友们分享一款安卓手机上非常实用的一键ROOT工具《z4root》，可能很多网友会问“z4root怎么用？”，小曹想说这个问题是完全不用担心的，z4root是一款傻瓜级的越狱软件，使用起来非常简单，安装完成后让你想装什么软件就装什么软件，想删除什么就删什么，即便你的手机被定制了许多商业程序，也都可以被一一删除。 现在小曹先来讲解一些关于root权限的相关知识，让椒友们可以更加了解自己的手机，同时也可以快速的使用root软件进行一键root。 Root什么意思 在 Unix系统（如AIX、BSD等）和类UNIX系统（如Debian、Redhat、Ubuntu等各个发行版的Linux）中，系统的超级用户一般命名为root。root是系统中唯一的超级用户，具有系统中所有的权限，如启动或停止一个进程，删除或增加用户，增加或者禁用硬件等等。 root就是手机的神经中枢，它可以访问和修改你手机几乎所有的文件，这些东西可能是制作手机的公司不愿意你修改和触碰的东西，因为他们有可能影响到手机的稳定，还容易被一些黑客入侵（Root是Linux等类UNIX系统中的超级管理员用户帐户。） root权限获取的好处 1.可以备份系统。 2.使用高级的程序，例如屏幕截图、root explorer等等， 3.修改系统的内部程序 4.将程序安装到SD卡中（Android2.2以下默认是不支持的） 注明：一键ROOT工具《z4root》并不能支持所有的安卓手机进行root，请先查明机型是否支持。 支持的主流机型包括： Samsung Galaxy S (All variants) 摩托罗拉Backflip 索尼爱立信X10 索尼爱立信Xperia Mini 摩托罗拉Droid 2 三星Galaxy Tab 三星Galaxy I5700

安卓手机怎样获取ROOT权限

安卓手机如何获得ROOT特权 最近有很多朋友抱怨，手机自带的许多系统程序，删除不掉，占用了大量内存，导致手机变慢，变卡。这个教程可以教给大家如何获得root特权，轻而易举的删除手机里的系统程序。这里有几个步骤，不明白的可以留言。我会竭尽全力，悉心为您解答。 准备： 一，如果你使用的是Windows XP的操作系统，首先得在电脑上安装.NET Framework v2.0版或更高版本，不然会无法运行此软件。 微软官方下载地址： https://www.sodocs.net/doc/eb5807065.html,/downloads/zh-cn/details.aspx?FamilyID=0856eacb-4362-4b0d-8edd-a ab15c5e04f5 二，安装手机驱动，由于Android机型众多，你使用的是什么品牌的手机，就去这个品牌的官方网站上下载相应的套件或驱动安装在你的电脑上，记住是你手机的官方网站，然后找到你的机型再下载，不是百度出来的下载地址。 三，完成前面两步，准备手机数据线，在手机设置>>应用程序>>开发中勾上USB调试四，下载SuperOneClick，点击这里，然后解压缩（如果多次严格按教程操作无法破解，请点这里下载老版本SuperOneclick进行破解） 破解： 完成以上四步后，将手机与电脑连接，选择USB充电模式，解压 SuperOneClickv1.9.1-ShortFuse.zip，找到里面的SuperOneClick.exe，双击运行，界面就出来了，以下图片均可点击放大

不要看界面上的按钮很多，其实你只要点最左边的Root就行了！就是这个按钮 然后静待，如果超过两分钟都没有提示，请拔掉手机数据线，彻底关掉电脑上的91助手或其它管理软件 ，重新连上手机，再点Root. 下面是笔者破解实测，点击Root后，稍等一会儿，出来提示，见下图

超级用户权限root

一、关于root Root超级用户权限授权程序，国外有Root权限的自制ROM（只读存储器（read only memory））大多都是集成这个程序，本版自带中文，设置选项比Superuser permission更加丰富。- 授予和管理手机上的超级权限（root）- 需要手机已经Root，或者未锁定的Recovery Image - 支持最新的CM6 ROM. Android系统之所以没有在最初为用户开启root权限，是为了保证手机的稳定和安全性，所以接下来小编再推荐一个既可以赋予软件root权限，又可以管理root权限分配的软件——超级权限管理SuperUser。通过超级权限管理SuperUser你可以看到手机中有哪些程序在使用root权限,点击右侧的小按钮就可以开启或禁止一个程序使用root权限。 如果你想要了解这些程序都在什么时间使用root权限做了什么，可以查看具体的日志，只不过，日志的内容比较笼统难懂，只说明了程序在某个时间被允许或被切换。另外，这款软件是三款软件中支持机型最多的一键root工具，摩托罗拉、三星和HTC的主流机型几乎都能使用它。 二、为什么要获得Android的root权限 01、root权限跟administrator权限可以理解成一个概念 root是Linux系统中的超级管理员用户帐户,安卓系统是基于Linux为平台开发的。该帐户拥有整个系统至高无上的权利,所有对象他都可以操作,所以很多黑客在入侵系统的时候,都要把权限提升到root权限,也就是将自己的非法帐户添加到root用户组. administrator是windows nt内核系统中的超级管理员用户帐户,也拥有最高的权限 系统的最高权限啦！想做什么都可以。 02、获得ROOT关键能进RECOVERY进行刷机，其次某些软件的使用需要ROOT 03、root权限跟SYSTEM权限可以理解成一个概念(高于Administration权限)。root是Linux和unix系统中的超级管理员用户帐户,该帐户拥有整个系统至高无上的权利,所有对象他都可以操作，所以很多黑客在入侵系统的时候,都要

手机手动root获得最高权限

第一次小尝试自己手动root手机,记下步骤. 第一步：正确安装驱动 第二步：刷入recovery 第三步: 下载ROOT包 第一步：正确安装驱动 1 打开手机的USB调试，下载安装驱动（也可以使用豌豆荚自动安装） 2 数据线连接至电脑 3检查驱动是否正确安装，在设备管理器--出现Android Phone及此项下 正确出现Android Composite ADB Interface项表明驱动已经正确安装 第二步：刷入recovery 1.请先确保驱动已经正确安装，关掉豌豆夹，USB调试正确打开和手机和电脑保持正确的连接 2.下载附件recovery5.5.0.4_AscendP1.exe 3.运行recovery5.5.0.4_AscendP1.exe 按照提示选择你刷入Recovery

第三步下载[对应]ｒｏｏｔ包 [华为p1] 一、手动方式： 1、下载ROOT包放置到SDCARD 2、关机，按住音量上+开机键开机，并按住两键不放，直到进入新recovery 3、选择“从SD卡选择刷机包”［这时选择是声音上下键，确定是开机键］ 4、再选“从SD卡选择ZIP文件” 5、再找到刚下载的zip刷机包确认 6、刷完后，返回首菜单，选择“立即重启系统”重启手机: 二、自动方式[新手小白推荐】： 1、下载ROOT包放置到手机sd卡根目录 2、打开root.zip文件，将里面的genokolar_command文件解压出来放到内置卡根目录 3、关机，音量上+电源键开机* 4、recovery会自动完成刷机并重启 关于全自动安装： 1、将支持全自动安装的刷机包放置到SD卡下【不要改变ZIP的文件名】 2、将ZIP包内的genokolar_command这个文件解压出来放置到内置卡根目录 3、只需要进入recovery，将会检测到genokolar_command文件，然后会全自动安装刷机包

Nexus6P一键Root工具(支持7.1.1)

Nexus 5 5x 6p一键root工具 该工具不仅可以解决SuperSU二进制更新问题，还可以帮你成功Root手机，不管是安卓5.0 、6.0、7.0还是7.1.1都可以稳稳的获得Root权限 如对本软件有疑问请在下载完成后使用金山卫视和360安全卫士进行检测 欢迎加入群参与讨论：295449216 下载连接：链接：https://www.sodocs.net/doc/eb5807065.html,/s/1o8TjUNS 密码：rr8r Google Nexus One Click Root 的优点 1.完美支持安卓5.0、6.0、7.0、7.1、7.1.1 2.告别繁琐的SuperSU安装步骤，自动安装 3.不会出现更新su文件等问题，安装完成后直接使用SuperSU 4.安装完成后，不会修改手机系统，支持OTA升级 重要说明 1.此次安装不会清除任何数据，但为了您的数据安全，请提前做好数据备份，以防操作不当引起数据丢失

2.工具目前支持Nexus 5、5x、6P手机，其他手机请勿使用 3.使用工具前请确认手机已解锁 使用方法： 1.打开USB调试并安装好驱动 2.连接手机到电脑 3.点击Google Nexus One Click Root.exe软件即可正常安装 重要通知： 该软件是我与盟友一同制作的，目前我们都在一个玩机志愿者俱乐部用业余时间做一些使用的软件来供大家使用 如果经历允许，我们后续会为大家制作更多机型的Root工具，我们希望大家也能一起加入到我们的玩机俱乐部，为大家做一些方便实用的软件 产品更新&问题反馈 软件发布与问题讨论QQ群：295449216，欢迎大家进群讨论 以后工具如有更新我将会第一时间在群内进行分享，邀请大家体验 另外欢迎关注PunkyWind的微博账号，了解更多工具的开发进度，欢迎大家参与到开发中 使用方法： 1、安装驱动 下载驱动并安装 2、打开USB调试连接电脑。

中兴V880获取ROOT权限及刷机教程

中兴V880获取ROOT权限及刷机教程 中兴V880怎么刷机，中兴v880如何刷机，很多朋友拿到v880之后都有这样的疑问，本文为中兴V880刷机教程，教你如何让中兴V880获得ROOT权限，后面附中兴v880刷机视频供大家参考。 原来新出V880刷过,方法很简单,后来转到HTC G11专区去了,最新朋友有台机子,找到好久找到原来教程比较适合新手的刷机教程 1:手机上设置USB模式:主桌面-菜单(按键中间那个)-设置-应用程序-未知来源打勾再点开发-USB调试打勾 2:电脑端安装91助手或者豌豆荚等平台:手机连上电脑,平台就会自己识别你的机子并且安装驱动,完毕后就可以用平台安装下面APK文件.

以下为刷机详细过程和资料:分3个部分:一键ROOT手机系统,电脑(pc)平台自动加载recovery程序,recovery刷机步骤 ①一键速度ROOT手机系统 V880查询系统版本软件： 第一步:先用此软件测试你是那版中兴V880机子,安装此软件到手机后运行(ask mr pigfish),如果软件打开第一行有显示gen2 mode,就接着走第二步! 手机一键ROOT程序： 第二步:刷机需要ROOT.这个是中兴V880一键ROOT软件,安装此软件到手机运行 (z4root).选择第二个项(获取永久ROOT权限),ROOT完后手机会自动重启进入系统查看有无授权图标(授权管理).有就证明成功ROOT啦,现在也可以自己安装个文件管理器删除系统自带软件啦

②pc平台最简单安装中文recovery程序软件 pc平台中文一键安装recovery程序软件： 第一步：手机按HOME键(左下小房子按键)+声音下键+开机键同时按住到开机卡到Wo 图标界面.在就连接上电脑; 第二步：直接在电脑端打开此文件(电脑V880驱动需要完整).按程序文本提示要求一直按键盘任意键进行就可以啦.结束后手机会自动重启就可以啦.

HTC G18一键root权限获取图文教程

HTC G18一键root权限获取图文教程 刷入了recovery之后就应该给HTC G18获取ROOT权限了，只要具备了这两个条件以后刷机都不成问题。那么HTC G18该怎么才能够取得ROOT权限呢?小编马上就回来为大家揭开这个神秘的谜底。 首先，手机要获取ROOT权限,需先解锁S-OFF。(没有解锁的请在安软市场搜索“HTC 通用解锁教程”) HTC G18 ROOT第1步：刷入recovery(已经刷入的童鞋可以跳过，流程不清晰的童鞋可以点击这里跳转) 1、下载文件G18 PG58IMG.zip，改名为PG58IMG.zip，并复制到存储卡根目录。

2、取消手机快速启动(设置—电源—快速启动取消勾选)，然后关闭手机。 3、按住音量下+电源键开机，进入HBOOT。 4、手机检测到PG58IMG.zip，询问是否升级。 5、按音量上选择Yes。 6、刷完重启。 7、去存储卡里删除PG58IMG.zip HTC G18 ROOT第2步：永久ROOT 1、下载文件G18 ROOT.Zip并复制到内存卡根目录,取消手机快速启动并关机，按住音量下+电源键开机，进入手机的HBOOT界面。 2、选择RECOVERY，按开机键，这个时候会进入ClockworkMod Recovery v5.0.0.8 界面。 3、选择“install zip from sdcard” 4、然后选择“Choose zip from sdcard” 5、然后选择“ROOT.zip” 6、然后选择“Yes - install "G14-ROOT.zip" 确认刷入即可进入刷机进程。 7、当出现"Install from sdcard complete"代表刷机结束，你可以返回Recovery主界面，选择"reboot system now"立即重启手机进入新系统。

安卓系统如何获得root权限,删除自带垃圾软件

首先声明：别乱删文件，按照步骤一步一步操作。乱删文件可能导致手机变砖头，本文只教你怎么删除自带多余的软件，变砖头后的善后事宜一概不管，请自觉联系维修点。 1.首先把群共享里面的这两个软件装到手机上 用usb连接电脑，下拉最上方的条目，选择usb已连接，然后选择打开usb存储设备。软件下载后存放在SD卡中（即电脑上多出来的那个硬盘）。把文件放到自己可以找的到的地方，然后选择电脑右下角的“安全删除硬件”确定后，去掉USB。用手机进“文件管理器”找到这两个文件，点击，会提示安装，安装好后退出。 2.装好后两个都打开看看 找到gingerbreak图标，打开，出现本图： 点ok确认，有三个选项记住选第二个项

选择第二个选项，即（root device）。之后请等待，直到手机自动重启。等待和重启的过程很慢，中间不需要操作，等几分钟就好。记住是自动重启（正常情况都会自己重启，如果长时间>10min以上，就自己动手开关机吧）手机重启后就获得ROOT的权限了。 3. 现在你能在菜单里面找到权限管理 （骷髅头）图标（可以点进去看看。出现下图 re管理器后面的点是不是绿色，如果是红色，点击一下变成绿色，确定为绿色后退出）

4.再去找那个帽子形状的图标（re管理器） 打开会显示很多文件夹列表如图：点最上面的一行“挂载为读写”。显示为已挂载为读写后，向下拖动屏幕，找到system文件夹，点击进去，找到app文件夹。系统自带的软件都在这个system - app 里面。 5.接下来就是清垃圾软件了，这部很关键，没有列出来的软件千万不能删，想变成砖头的自便好了。 我们先以飞信做示范（我跟飞信有仇） 在菜单里面看一眼他长什么样子，日后好对他下手 按照步骤4依次打开system- app APP里面就是系统自带的软件了 进去后如图所示：

关于三星galaxy获取root权限的方法

关于三星galaxy获取root权限的方法 三星的galaxy弄了几个程序上去以后，首先发现的问题就是没有办法在win32环境下直接用adb连上galaxy手机，后来在网上找到了国外高手修改过的adb程序，现在把galaxy连入adb已经没问题了。 但是随之而来的是galaxy上面用adb shell以后，运行su的时候，看到了permission denied 的提示字样。很是郁闷，这样一来连基本的TaskManager软件都无法工作，更不要说类似swiftp之类的host类的ftp软件了，对于开发而言，开发一些需要能力相对高一点的软件就成为了mission impossible的事情——用两个字来形容一下“不爽”。 于是乎，需要想办法把这个root的限制突破一下。在这里偶很好奇，为什么消费者自己购买的手机连root的权限都无法得到，而只能通过一些“不和谐”的方法来得到这样的权限？！这个机器难道不是已经属于消费者了吗？关于什么安全性之类的论点，偶个人认为都是一些托词罢了，这个世界都是处在一个动态的平衡中的，有矛就一定会有盾；打开了root权限，有了病毒或者安全性问题，那么就一定有人有公司开发相关的防火墙以及其他的工具软件。为什么要通过这种不太高明的手段，通过权限去限制呢？！（注，以上纯属个人观点，有任何意见欢迎讨论） 看来国外的黑客们又是先行一步，在偶开始google的时候，就已经发现了hdblog.it这个网站公布了galaxy的获取root权限的方法，方法虽然简单，但是这个galaxy毕竟是samsung 所开发的，很多地方都与htc的风格（包括快捷键）都有很大的不同。偶刚刚看hdblog.it上面的hack向导的时候也是一头雾水，后来经过偶的摸索，总算理出来了头绪，下面就把偶的做法贴出来，虽然目前国内samsung的galaxy i7500还没有上市，但是应该很快就会在国内上市的。 英文好的朋友可以参考如下链接：https://www.sodocs.net/doc/eb5807065.html, http://forum.hdblog.it/forumdisplay.php?f=80 （1)准备工作 要得到root权限，第一步一定是收集资料，下载工具了。本文的最后会有一个.txt结尾的文件，里面有一个url，通过这个url就可以下载到取得galaxy的root权限的所有工具和img。但是需要说一下的是：hdblog.it中的作者已经提到过请不要把该txt中的url公布在互联网上，这样，这个url由于下载的人过多很快就会失效的。（毕竟要给后来人留下点东西嘛） 下载该工具包后，就是解压缩，里面如果不出意外的话应该看到三个文件： adb： 这个就是传说中的经过了修改的adb了，只有通过它才能够在linux环境下访问galaxy i7500（这一点偶已经亲手验证过了，在偶的slackware 12.2平台上确实是可以连接galaxy的）。 fastboot：