Fireblight <i>Erwinia amylovora</i> and weather: a comparison of warning systems

Billing, Eve

doi:10.1111/j.1744-7348.1980.tb04756.x

Cited by 30 publications

(39 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Fire blight is distributed in the temperate climate zones where temperatures of 15 to 20°C are accompanied by high relative humidity, which favors infection of a host plant by E. amylovora (3,8,9,48). During screening for temperature-dependent gene expression in this pathogen, a gene was identified which presumably encodes a multidrug efflux transporter (14).…”

Section: Resultsmentioning

confidence: 99%

NorM, an Erwinia amylovora Multidrug Efflux Pump Involved in In Vitro Competition with Other Epiphytic Bacteria

Burse

Weingart

Ullrich

2004

Appl Environ Microbiol

View full text Add to dashboard Cite

Blossoms are important sites of infection for Erwinia amylovora, the causal agent of fire blight of rosaceous plants. Before entering the tissue, the pathogen colonizes the stigmatic surface and has to compete for space and nutrient resources within the epiphytic community. Several epiphytes are capable of synthesizing antibiotics with which they antagonize phytopathogenic bacteria. Here, we report that a multidrug efflux transporter, designated NorM, of E. amylovora confers tolerance to the toxin(s) produced by epiphytic bacteria cocolonizing plant blossoms. According to sequence comparisons, the single-component efflux pump NorM is a member of the multidrug and toxic compound extrusion protein family. The corresponding gene is widely distributed among E. amylovora strains and related plant-associated bacteria. NorM mediated resistance to the hydrophobic cationic compounds norfloxacin, ethidium bromide, and berberine. A norM mutant was constructed and exhibited full virulence on apple rootstock MM 106. However, it was susceptible to antibiotics produced by epiphytes isolated from apple and quince blossoms. The epiphytes were identified as Pantoea agglomerans by 16S rRNA analysis and were isolated from one-third of all trees examined. The promoter activity of norM was twofold greater at 18°C than at 28°C. The lower temperature seems to be beneficial for host infection because of the availability of moisture necessary for movement of the pathogen to the infection sites. Thus, E. amylovora might employ NorM for successful competition with other epiphytic microbes to reach high population densities, particularly at a lower temperature.

show abstract

Section: Resultsmentioning

confidence: 99%

NorM, an Erwinia amylovora Multidrug Efflux Pump Involved in In Vitro Competition with Other Epiphytic Bacteria

Burse

Weingart

Ullrich

2004

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…A more rigorous approach was therefore attempted using existing predictive models available in the literature, mainly that of Billing (1980a). However this would not take into account the detailed biology of the disease.…”

Section: Methodsmentioning

confidence: 99%

Using weather records and available models to predict the severity of fireblight should it enter and establish in Australia¹

Roberts

1991

EPPO Bulletin

View full text Add to dashboard Cite

Australia is free from fireblight, a serious apple and pear disease. Published models and weather data from all major apple and pear‐producing areas of Australia were used to predict the possible severity of the disease and losses in production should the disease enter and establish in Australia. The results suggest that fireblight could be severe in most areas in most seasons. In the worst case, with every area affected, this could result in up to 20% losses in apple production and up to 50% losses in pear production.

show abstract

“…Leaf rust development is a function of temperature fluctuation, hourly leaf wetness, relative humidity and wind movement when sufficient amount of virulent, initial inoculum are deposited on a susceptible wheat variety. Disease forecasts utilizing environmental conditions and indirect assessment if initial inoculum have been reported (Billing, 1974(Billing, , 1980Castor et al, 1975;Stevens, 1934;Thomson et al, 1982). Urediniospore inoculum effects on leaf rust development have been described in quantitative terms (Burleigh et al, 1969;Dirks and Romig, 1970;Subba Rao et al, 1990).…”

Section: Discussionmentioning

confidence: 99%

Polynomial Regression Models to Characterize Environmental Conditions Conducive for Leaf Rust Development on Winter Wheat in Mississippi

Khan¹,

Trevathan²

1998

Pakistan J. of Biological Sciences

View full text Add to dashboard Cite

Environmental conditions conducive for leaf rust development were determined at Starkville, MS, during the 1991-92 and 1992-93 wheat growing seasons. Four wheat varieties, grown in a randomized complete block design and infected by natural inoculum, were rated weekly for leaf rust severity. The relationship of weekly maximum, minimum and average air temperatures, dew point, relative humidity, total rainfall, soil temperature, solar radiation and wind movement to leaf rust severity was determined by polynomial regression. Leaf rust severity for each of the varieties was different under differing environmental conditions. In 1992, the relationship between leaf rust severity and weekly air and soil temperatures and solar radiation was linear for most varieties. In 1992, significantly higher solar radiation and soil temperature, lower rainfall and less wind movement contributed to greater leaf rust severity compared to 1993. During two seasons neither quadratic nor qubic regression models fit the data well for most of the environmental parameters. During 1992 leaf rust development on all the four varieties in relation to weekly maximum, minimum and average air temperature and soil temperature was best explained by linear regression models. During 1993, the relationship of environmental condition to leaf rust severity recorded only on Pioneer varieties was best explained by linear regression models. The environmental conditions characterized for maximum leaf rust severity on four varieties included 25-27, 15-20, 21-23EC maxi, min, eve air temperatures and 85-90 percent relative humidity respectively.

show abstract

Fireblight Erwinia amylovora and weather: a comparison of warning systems

Cited by 30 publications

References 12 publications

NorM, an Erwinia amylovora Multidrug Efflux Pump Involved in In Vitro Competition with Other Epiphytic Bacteria

NorM, an Erwinia amylovora Multidrug Efflux Pump Involved in In Vitro Competition with Other Epiphytic Bacteria

Using weather records and available models to predict the severity of fireblight should it enter and establish in Australia¹

Polynomial Regression Models to Characterize Environmental Conditions Conducive for Leaf Rust Development on Winter Wheat in Mississippi

Contact Info

Product

Resources

About

Fireblight Erwinia amylovora and weather: a comparison of warning systems

Cited by 30 publications

References 12 publications

NorM, an Erwinia amylovora Multidrug Efflux Pump Involved in In Vitro Competition with Other Epiphytic Bacteria

NorM, an Erwinia amylovora Multidrug Efflux Pump Involved in In Vitro Competition with Other Epiphytic Bacteria

Using weather records and available models to predict the severity of fireblight should it enter and establish in Australia1

Polynomial Regression Models to Characterize Environmental Conditions Conducive for Leaf Rust Development on Winter Wheat in Mississippi

Contact Info

Product

Resources

About

Using weather records and available models to predict the severity of fireblight should it enter and establish in Australia¹