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

More documents

Recommendations

Info

Figure 2. GWSS killed by B. bassiana and M. anisopliae. Bioassay 3 This assay was conducted using only 10 9 conidia/mL concentration and 10 laboratory-reared GWSS per isolate. All the isolates from the previous bioassay were used in this assay except for PcBb1, which was replaced by the B. bassiana isolate from S. festinus (SfBb1). This assay had also suffered from very high mortality and all the insects died within 5 days after the treatment. Fungal infection was seen in only one GWSS cadaver treated with SfBb1. CONCLUSIONS The fact that GWSS is susceptible to entomopathogenic fungi such as B. bassiana is promising. Although infections occurred only at relatively high concentrations, there is enough variability in B. bassiana as a species to suggest other isolates may be more virulent. Efforts will continue to obtain isolates from collaborators and from likely GWSS host habitat in California for further laboratory evaluation and eventual field application. REFERENCES Galaini-Wraight,S., S.P. Wraight, R.I. Carruthers, B.P. Magalhaes, and D.W. Roberts. 1991. Description of a Zoophthora radicans (Zygomycetes, Entomophthoraceae) epizootic in a population of Empoasca kraemeri (Homoptera, Cicadellidae) on beans in central Brazil. J. Invertebr. Pathol. 58: 311-326. Grafton-Cardwell, E.E. and C. Kallsen. 2001. Efficacy of insecticides used for glassy-winged sharpshooter control in citrus. Pierce’s Disease Research Symposium, Dec 5-7, 2001. pp. 32-34. Hywel-Jones, N.L., H.C. Evans, and Y. Jun. 1997. A re-evaluation of the leafhopper pathogen Torrubiella hemipterigena, its anamorph Verticillium hemipterigenum and V. pseudohemipterigenum sp. nov. Mycol. Res. 101: 1242-1246. Magalhaes, B.P., R.A. Humber, E.J. Shields, and D.W. Roberts. 1991. Effects of environment and nutrition on conidium germination and appressorium formation by Zoophthora radicans (Zygomycetes, Entomophthorales): a pathogen of the potato leafhopper (Homoptera, Cicadellidae). Environ. Entomol. 20: 1460-1468. Matsui, T., H. Sato, and M. Shimazu. 1998. Isolation of an entomogenous fungus, Erynia delphacis (Entomophthorales: Entomophthoraceae), from migratory planthoppers collected over the Pacific Ocean. Appl. Entomol. Zool. 33: 545-549. McGuire, M.R., M.J. Morris, E.J. Amburst, and J.V. Maddox. 1987. An epizootic caused by Erynia radicans (Zygomycetes: Entomophthoraceae) in an Illinois Empoasca fabae (Homoptera: Cicadellidae) population. J. Invertebr. Pathol. 50: 78- 80. Mizell, R.F. and D.G. Boucias. 2002. Mycopathogens and their exotoxins infecting glassy-winged sharpshooter: survey, evaluation, and storage. Pierce’s Disease Research Symposium, Dec 15-18, 2002. pp. 161-162. Wells, J.M., B.C. Raju, H.Y. Hung, W.G. Weisburg, L. Mandelco-Paul and D.J. Brenner. 1987. Xylella fastidiosa gen. nov., sp. nov.: gram-negative, xylem-limited, fastidious plant bacteria related to Xanthomonas spp. Int. J. Syst. Bacteriol. 37: 136-143. FUNDING AGENCIES Funding for this project was provided by the University of California’s Pierce’s Disease Grant Program. a - 351 - b
IDENTIFICATION OF MECHANISMS MEDIATING COLD THERAPY OF XYLELLA FASTIDIOSA-INFECTED GRAPEVINES Project Leader: Bruce Kirkpatrick Dept. of Plant Pathology University of California-Davis Davis, 95616 Cooperator Melody Meyer Dept. of Plant Pathology University of California-Davis Davis, 95616 Reporting Period: The results reported here are from work conducted from July 2004 to November 2004. ABSTRACT Preliminary xylem sap composition studies were conducted in February 2004 using Cabernet sauvignon and Pinot noir grapevines growing in Placerville (cold winter temperature) and UC Davis (warmer temperatures). The pH of xylem sap from both varieties was almost a full unit lower in vines grown in cold temperatures versus warm. A similar trend also occurred with sap osmolarity, however the differences were not as great. Because these vines were grown under different management practices and on different rootstocks these results must be considered preliminary. In 2004 we established four field sites in Shasta, Placer, Mendocino and Yolo counties to repeat these measurements on clonal vines that were grown in 5-gallon pots at University of California, Davis. One-half of the vines were inoculated with Xf while the other half is uninoculated controls. Sap will be collected from the vines during the late winter and pH, osomolarity, carbohydrates, organic acids and abscisic acid (ABA) will be measured and compared. The vines will be returned to University of California, Davis at bud break and observed for the development of PD symptoms and tested by PCR to determine if any of the vines were “cold cured” of their infection. Similar experiments using potted vines that will be exposed to defined cold temperature regimes in cold storage facilities located at University of California, Davis will be conducted in 2005. Proteins present in the collected xylem sap will be analyzed by PAGE and the identity of major or unique xylem sap proteins will be determined by sequencing them. Xf viability studies using buffers of various pHs, xylem sap from warm- and cold-treated vines will also be studied. The goal of this research is to understand the physiological/biochemical basis of cold therapy that was first documented by A.H. Purcell. INTRODUCTION The geographical distribution of Pierce’s disease (PD) in North America is strongly associated with the severity of winter temperatures, i.e. PD does not occur in New York, the Pacific Northwest nor at high altitudes in S. Carolina, Texas and even California (Hopkins and Purcell, 2002). Sandy Purcell demonstrated that relatively brief exposures to sub-freezing temperatures can eliminate Xylella fastidiosa in some percentage of cold treated V. vinifera grapevines, however some of the coldest temperatures he used killed the vines (Purcell 1977, 1980). He also found that a higher percentage of vines that were moderately susceptible to PD such as Cabernet sauvignon, were cured by cold therapy treatments compared to susceptible varieties such as Pinot noir. Purcell’s group also showed that whole, potted vines exposed to low temperatures had a higher rate of recovery than PD-affected, detached bud sticks exposed to the same cold temperatures (Feil, 2002). Clearly, some factor(s) that were expressed in the intact plant, but not in detached bud sticks, helped eliminate Xf from the plants. Our objective is to elucidate the physiological/biochemical basis that mediates cold therapy and to identify the physiological/biochemical factor(s) that occur or are expressed in cold treated vines that eliminate Xf. If such factor(s) are found, it may be possible to induce their expression under non-freezing temperatures and potentially provide a novel approach for managing PD. OBJECTIVES 1. Develop an experimental, growth chamber temperature regime that can consistently cure Pierce’s disease affected grapevines without causing unacceptable plant mortality. 2. Analyze chemical changes such as pH, osomolarity, total organic acids, proteins and other constituents that occur in the xylem sap of cold-treated versus non-treated susceptible and less susceptible Vitis vinifera varieties. 3. Assess the viability of cultured X. fastidiosa cells growing in media with varying pH and osomolarity and cells exposed to xylem sap extracted from cold- and non-treated grapevines. 4. Determine the effect of treating PD-affected grapevines with cold plant growth regulators, such as abscisic acid (ABA), as a possible therapy for PD. RESULTS AND CONCLUSIONS Objective 1 The same varieties used by Purcell (1977, 1980) and Feil (2002) in previous cold therapy studies, Pinot noir (PD-susceptible) and Cabernet sauvignon (moderately resistant to PD) grapevines grafted on 101-14 rootstock were inoculated with Xf in the spring of 2004 using a pinprick inoculation procedure (Hill and Purcell, 1995; Purcell and Saunders, 1999). The vines were grown in five gallon pots in a greenhouse using a nutrient-supplemented irrigation regime. Treatment vines were inoculated with the Stagg’s Leap strain of Xylella fastidiosa, whereas control vines were inoculated with water. During late summer and fall, the plants were moved into a screen house in order to acclimatize them to decreasing temperatures. While in the screen - 352 -
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 and 150:
Strain Name Host of Origin County o
Page 151 and 152:
ROLE OF ATTACHMENT OF XYLELLA FASTI
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: Isolation of Fungal Pathogens Soil
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?