Impact Of Host Plant Xylem Fluid On Xylella Fastidiosa Multiplication ...

More documents

Recommendations

Info

REFERENCES Belkum, A., Scherer, S., Alphen, L., and Verbrugh, H. 1998 Short-sequence DNA repeats in prokaryotic genomes. Microbiology and Molecular Biology Review. V. 62, 2:275-293. McDonald, B., Linde, C., 2002 Pathogen population genetics, evolutionary potential, and durable Resistance. Annu. Rev. Phytopathol. 40:349-379 FUNDING AGENCIES Funding for this project was provided by the CDFA Pierce’s Disease and Glassy-winged Sharpshooter Board. - 209 -
ROLE OF ATTACHMENT OF XYLELLA FASTIDIOSA TO GRAPE AND INSECTS IN ITS VIRULENCE AND TRANSMISSIBILITY Project Leaders: Steven E. Lindow University of California Division of Plant and Molecular Biology Berkeley, CA 94720-3112 icelab@socrates.berkeley.edu Alexander H. Purcell University of California Division of Insect Biology Berkeley, CA 94720-3112 Cooperator: Helene Feil University of California Division of Plant and Molecular Biology Berkeley, CA 94720-3112 icelab@socrates.berkeley.edu Reporting period: The results reported here are from work that commenced on June 1, 2004. ABSTRACT Attachment of Xylella fastidiosa to xylem vessels and insect vectors may be required for virulence and transmission; therefore we have individually disrupted fimA, fimF, xadA, and hecA to assess their role in adhesion to plants and in the disease process. We performed adhesion assays using each mutant and wild-type separately as well as combination of two of the mutants and observation of the phenotypes of these mutants under a scanning electron microscope is underway. Patterns of cell adhesion and aggregation of mutants on surfaces lead us to hypothesize that fimA and fimF are important in cell-to-cell aggregation while xadA and hecA are involved in the first steps of adhesion of bacteria to the plant host. Rooted grapevine cuttings were inoculated with FimA-, FimF-, XadA-, HecA-, and wild-type X. fastidiosa ‘Temecula’ or ‘STL’. A higher incidence and severity of disease was observed in vines inoculated with the wild-type X. fastidiosa strain compared with FimA-, FimF-, XadA- or HecA- mutant strains. Similarly, wild-type strain STL strain of X. fastidiosa resulted in more vines with symptoms than FimA-, FimF- or XadA- mutants of this strain indicating that the process of attachment appears to involve similar genes in both the Temecula and STL strains. It thus appears that successful colonization of plants by X. fastidiosa requires both cell-to-cell and cell-to-surface attachment. To distinguish the various mutants from each other in mixed inoculations and to determine what factors affect attachment of the mutants we have constructed disrupted fimA vectors for use in a gfp marked Xylella fastidiosa. This will allow us to distinguish the FimA- cells from other cells in a mixture adhesion assay using fluorescence microsopy and to follow these cells in grape following inoculation with these mutants. Because hecA is a large gene, we are also disrupting various locations within the HecA gene. We will test these different HecA- mutants in inoculation experiments to determine the role of HecA in virulence of X. fastidiosa to grape. INTRODUCTION Adhesion is a well-known strategy used by phytopathogenic bacteria to initiate colonization of their plant hosts and a precursor step to invasion (Romantschuk et al. 1994). Xylella fastidiosa possesses many genes involved in attachment or adhesion. Simpson et al. (2000) identified 26 genes encoding proteins involved in the biogenesis and function of Type 4 fimbriae filaments (pilA, B, C…). We have focused on the fimbrial operon, which is composed of 6 genes (fimA, ecdD, fimC, D, E, and F). Even though the fimbrial mutant cells had less fimbriae than the wild type cells as seen in scanning electron micrographs, the cells seemed to still be able to attach to surfaces by another mechanism (Feil et al. 2003) (Figure 1A). This suggested that fimbriae are more important in cell-to-cell adhesion than in cell-to-surface adhesion. While FimA and FimF were found to be important in cell-to-cell aggregation (Feil et al. 2003) the initial attachment of X. fastidiosa to plants must involve other factors. The goal of this research was thus to assess the relative role of different fimbrial and non-fimbrial adhesins in the attachment process and to determine their role in the disease process. Among the afimbrial adhesins of X. fastidiosa we chose XadA and HecA to study because genes homologous to these in other bacteria were found to be virulence determinants. OBJECTIVES 1. Determine the role of adhesins other than those found in the fimbrial operon, in particular of the adhesin XadA and hemagglutinin HecA in the attachment and virulence of X. fastidiosa in grape. 2. Characterize the behavior of the fimbrial and adhesion mutants of Xylella fastidiosa in grape and to compare this behavior over time via expression analysis. 3. Determine what factors affect attachment of wild-type or mutant cells to grape 4. Determine if these mutants can attach to the insect vector and be transmitted to grape. - 210 -
Page 1 and 2:
IMPACT OF HOST PLANT XYLEM FLUID ON
Page 3 and 4:
0.18 600 Optical density 0.16 0.14
Page 5 and 6:
OPTIMIZING MARKER-ASSISTED SELECTIO
Page 7 and 8:
esistant and susceptible genotypes
Page 9 and 10:
MAP BASED IDENTIFICATION AND POSITI
Page 11 and 12:
esistant genotypes are in process a
Page 13 and 14:
BREEDING PIERCE’S DISEASE RESISTA
Page 15 and 16:
Progeny from crosses of field resis
Page 17 and 18:
a = (1=low, 4= high); b = (1=green,
Page 19 and 20:
- 78 -
Page 21 and 22:
- 80 -
Page 23 and 24:
v.8) for differences due to the pla
Page 25 and 26:
SHARPSHOOTER FEEDING BEHAVIOR IN RE
Page 27 and 28:
correlated with all other findings
Page 29 and 30:
EFFECTS OF FEEDING SUBSTRATE ON RET
Page 31 and 32:
REFERENCES Bextine, B. and T. Mille
Page 33 and 34:
will also provide insights into the
Page 35 and 36:
OBJECTIVES 1. Determine glassy-wing
Page 37 and 38:
GWSS per 30 s sweep (seasonal avera
Page 39 and 40:
ELISA for the presence of GWSS egg
Page 41 and 42:
Project Leader: Thomas P. Freeman E
Page 43 and 44:
Freeman, T. P., R. A. Leopold, D. R
Page 45 and 46:
pathogen, when they move into viney
Page 47 and 48:
A NOVEL IMMUNOLOGICAL APPROACH FOR
Page 49 and 50:
1.6 GWSS Adults That Fed on Protein
Page 51 and 52:
Hagler, J.R. & S.E. Naranjo. 2004.
Page 53 and 54:
RESULTS: Oviposition Survey Wild gr
Page 55 and 56:
Host specificity testing: No-choice
Page 57 and 58:
currently employed morphological ch
Page 59 and 60:
increase our present understanding
Page 61 and 62:
BIOLOGY AND MORPHOMETRIC ANALYSIS O
Page 63 and 64:
Table 1. Mean a developmental durat
Page 65 and 66:
EFFECTS OF USING CONSTANT AND CYCLI
Page 67 and 68:
REFERENCES Gautam, R. D. 1986. Effe
Page 69 and 70:
PARASITISM OF THE GLASSY-WINGED SHA
Page 71 and 72:
Table 1. Parasitism by G.ashmeadi o
Page 73 and 74:
Project Leader: Robert F. Luck Dept
Page 75 and 76:
A more interesting analysis using t
Page 77 and 78:
MYCOPATHOGENS AND THEIR EXOTOXINS I
Page 79 and 80:
POPULATION DYNAMICS AND INTERACTION
Page 81 and 82:
No egg masses were recorded on olea
Page 83 and 84:
EXPLORATION FOR FACULTATIVE ENDOSYM
Page 85 and 86:
Although Baumannia and Wolbachia we
Page 87 and 88:
EFFECTS OF SUBLETHAL DOSES OF IMIDA
Page 89 and 90:
Table 2. Mortality and flight perfo
Page 91 and 92:
A NOVEL METHOD TO INDUCE OVIPOSITIO
Page 93 and 94:
REFERENCES Brodbeck, B. V., P. C. A
Page 95 and 96:
Cohorts H. coagulata neonates were
Page 97 and 98:
REFERENCES Blua, M. J. and D. J. W.
Page 99 and 100: Figure 2 shows the average numbers
Page 101 and 102: REPRODUCTIVE BIOLOGY AND PHYSIOLOGY
Page 103 and 104: REFERENCES Blua, M. J., Phillips, P
Page 105 and 106: - 164 -
Page 107 and 108: - 166 -
Page 109 and 110: RESULTS Some plant families had no
Page 111 and 112: Table 5. Winter, spring and summer
Page 113 and 114: 16S rDNA is by far the most sequenc
Page 115 and 116: DNA MICROARRAY AND MUTATIONAL ANALY
Page 117 and 118: Inhibition of biofilm is BSA concen
Page 119 and 120: CULTURE-INDEPENDENT ANALYSIS OF END
Page 121 and 122: Borneman, J., M. Chrobak, G. Della
Page 123 and 124: P (CFU P OBJECTIVE 1. Determine the
Page 125 and 126: Purcell, AH and SR Saunders. 1999a.
Page 127 and 128: Figure 1: Southern blot of tolC::ap
Page 129 and 130: Project Leader: David Gilchrist Dep
Page 131 and 132: III. Production of transgenic plant
Page 133 and 134: RESULTS Construction of cDNA Librar
Page 135 and 136: CONCLUSIONS Genetic resistance and
Page 137 and 138: Mutagenesis of Xylella The EZ::TN T
Page 139 and 140: ISOLATION OF BACTERIOPHAGES SPECIFI
Page 141 and 142: Project Leader: Michele M. Igo Sect
Page 143 and 144: outer membrane fractions using two-
Page 145 and 146: 1995; Purcell and Saunders, 1999).
Page 147 and 148: DEVELOPMENT OF SSR MARKERS FOR GENO
Page 149: Strain Name Host of Origin County o
Page 153 and 154: wild-type cells was not conclusive
Page 155 and 156: DETERMINATION OF GENES CONFERRING H
Page 157 and 158: S1 S2 S3 S4 Nb123456789bb123456789b
Page 159 and 160: MULTILOCUS SEQUENCE TYPING TO IDENT
Page 161 and 162: GENOME-WIDE IDENTIFICATION OF RAPID
Page 163 and 164: Americas and since most of the plan
Page 165 and 166: EFFECTS OF CHEMICAL MILIEU ON ATTAC
Page 167 and 168: CONCLUSIONS Our overall objective i
Page 169 and 170: RESULTS Objective 1. We conducted t
Page 171 and 172: Redak, R. A., Purcell, A. H., Lopes
Page 173 and 174: In parallel, an “activating trans
Page 175 and 176: PATTERNS OF XYLELLA FASTIDIOSA INFE
Page 177 and 178: % of vessels 100 80 60 40 20 Mugwor
Page 179 and 180: DOCUMENTATION AND CHARACTERIZATION
Page 181 and 182: Magnolia002 showed more identity (9
Page 183 and 184: PLASMID ADDICTION AS A NOVEL APPROA
Page 185 and 186: GENETIC VARIABILITY OF XYLELLA FAST
Page 187 and 188: - 246 -
Page 189 and 190: probing activities). In preliminary
Page 191 and 192: the slow release valve was opened a
Page 193 and 194: 12. Hopkins DL (1977) Diseases caus
Page 195 and 196: The almost complete absence of info
Page 197 and 198: QUANTIFYING LANDSCAPE-SCALE MOVEMEN
Page 199 and 200: Table 1. The mean (±SD) ELISA read
Page 201 and 202:
EPIDEMIOLOGICAL ASSESSMENTS OF PIER
Page 203 and 204:
multiply to relatively high (easily
Page 205 and 206:
SPATIAL DATABASE CREATION AND MAINT
Page 207 and 208:
Project Leader: Thomas M. Perring D
Page 209 and 210:
Figure 2. Individual leaves from a
Page 211 and 212:
The state variables, process functi
Page 213 and 214:
DEVELOPMENT OF A FIELD SAMPLING PLA
Page 215 and 216:
Figure 1. Three main dispersion pat
Page 217 and 218:
- 276 -
Page 219 and 220:
- 278 -
Page 221 and 222:
OBJECTIVES 1. Track the movement of
Page 223 and 224:
REFERENCES 1. Beard, C.B., Cordon-R
Page 225 and 226:
cases, positive phloem samples were
Page 227 and 228:
EXPLOITING XYLELLA FASTIDIOSA PROTE
Page 229 and 230:
Figure 2. Polymer disk accumulation
Page 231 and 232:
CHARACTERIZATION OF NEONICOTINOIDS
Page 233 and 234:
EVALUATION OF RESISTANCE POTENTIAL
Page 235 and 236:
Project Leader: Doug Cook Dept. of
Page 237 and 238:
Based on the in silico analysis, de
Page 239 and 240:
CONTROL OF PIERCE’S DISEASE THROU
Page 241 and 242:
Figure 1. Oleander ‘White’ afte
Page 243 and 244:
RESULTS During the reporting period
Page 245 and 246:
DEVELOPMENT OF AN ARTIFICIAL DIET A
Page 247 and 248:
DESIGN OF CHIMERIC ANTI-MICROBIAL P
Page 249 and 250:
Neutrophil elastase Cecropin B Chim
Page 251 and 252:
and WTXb is very low (0.00-0.40%) a
Page 253 and 254:
100 100 0.056 North America 100 0.0
Page 255 and 256:
GENETIC DIFFERENTIATION AMONG GEOGR
Page 257 and 258:
Table 1. Single-populations descrip
Page 259 and 260:
MOLECULAR DISTINCTION BETWEEN POPUL
Page 261 and 262:
These novel observations strongly s
Page 263 and 264:
SEQUENCE DIVERGENCE IN TWO MITOCHON
Page 265 and 266:
Table 3. Pairwise sequence distance
Page 267 and 268:
DEVELOPMENT OF MOLECULAR DIAGNOSTIC
Page 269 and 270:
A. B. Relative Density of SCAR Band
Page 271 and 272:
THE ALIMENTARY TRACK OF GLASSY-WING
Page 273 and 274:
We have dissected and identified al
Page 275 and 276:
REALIZED LIFETIME PARASITISM AND TH
Page 277 and 278:
REPRODUCTIVE AND DEVELOPMENTAL BIOL
Page 279 and 280:
Mean adult longevity (days) 25 20 1
Page 281 and 282:
the proposed exploratory work; thes
Page 283 and 284:
SEARCHING FOR AND COLLECTING EGG PA
Page 285 and 286:
REFERENCES Hoddle, M. S. and S. V.
Page 287 and 288:
some Gram(+) bacteria, but are inac
Page 289 and 290:
7. Hultmark, D., et al., Insect Imm
Page 291 and 292:
Isolation of Fungal Pathogens Soil
Page 293 and 294:
IDENTIFICATION OF MECHANISMS MEDIAT
Page 295 and 296:
concentrations of 1.5 x 10 7 bacter
Page 297 and 298:
anchor it in the outer membrane (sh
Page 299 and 300:
SYMBIOTIC CONTROL OF PIERCE’S DIS
Page 301 and 302:
MANAGEMENT OF PIERCE’S DISEASE OF
Page 303 and 304:
pfF mutants are taken up by insects
Page 305 and 306:
Simpson, A. J. G., F. C. Reinach, P
Page 307 and 308:
Al-Wahaibi, A.K., Owen, and J. G. M
Page 309 and 310:
patterns differed among the lines,
Page 311 and 312:
Punja, Z.K. 2001. Genetic engineeri
Page 313 and 314:
mind, we conducted an additional st
Page 315 and 316:
REFERENCES Toscano, N., Byrne, F.,
Page 317 and 318:
RESULTS AND CONCLUSIONS The program
Page 319 and 320:
COMPATIBILITY OF INSECTICIDES WITH
Page 321 and 322:
More tests are in progress to addre
show all

Impact Of Host Plant Xylem Fluid On Xylella Fastidiosa Multiplication ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?