But, ours never seem to work or they might work one year but not the next.”, Fire blight can be a devastating bacteria for apple and pear growers. Out West, the research team of Ken Johnson of Oregon State University, Tim Smith of Washington State University, and Rachel Elkins from University of California Cooperative Extension have been investigating the use of a yeast product as well as some copper applications, and other existing materials. This resource incorporates practices growers may already be doing along with the research out of the western states and the OREI project on alternatives. Finally, remember the overall risk increases as bloom progresses as the fire blight pathogen is building up populations on flowers over time. It is formulated to target and control fire blight on plants like Chrysanthemums, Rhododendrons, Dieffenbachia, roses, crabapples, pyracantha, and pears. Oxytetracycline is also highly sensitive to degradation by sunlight and much of the activity is lost within one to two days after application. Quick overview The Tree Tech Microinjection OTC (Oxytetracycline) An effective oxytetracycline antibiotic for the control of bacterial and mycoplasma-related diseases such as fire blight, bacterial leaf scorch, X-disease, elm/ash yellows, elm phloem necrosis and lethal yellows of palm. Blossom blight infection can really kick start a fire blight epidemic because these infected flower clusters will ooze more inoculum out and bacteria will be spreading internally through the tree. Fire blight is a bacterial disease of rosaceous plants. Seeing how they work in combination, and which order of use is best, is part of the strategy. Growers in northern states are combating virulent outbreaks of fire blight, a disease becoming resistant to antibiotics, as seasons grow warmer and orchards have been reconfigured for higher yields. Michigan State University Extension advises that a tank-mix strategy of using streptomycin and oxytetracycline is not a resistance management strategy. To have a digest of information delivered straight to your email inbox, visit https://extension.msu.edu/newsletters. Fire blight can be a devastating bacterial disease to apple and pear trees, no matter what region. It’s spread primarily by pollen-bearing insects such as bees, and although it’s… Thus, warm and sunny days during bloom can very quickly lead to high percentages of flowers colonized with incredibly large fire blight populations. Fire blight is the most damaging bacterial disease that affects shrubs and trees in the Rosaceous family during warm spring weather combined with rains or heavy dews. The research team is also examining what type of phytotoxicity that copper applications will have on the fruit, and on the severity of russetting could develop. Johnson says the end goal of this project is devise integrated programs that prevent fire blight and do not cause russetting. The output of the MaryBlyt model, for example, is the epiphytic infection potential (EIP) number, which is an estimator of the risk of blossom blight infection. The research will also involve sterilizing the flower with Oxidate prior to the Blossom Protect application with the hopes of giving the yeast a higher success rate. They do, however, require free moisture, as little as 0.01 inch rain,  to move from the stigma tip down the outside of the style to the base of the flower where infection occurs through the nectaries. Sundin hopes to study how the yeast works with the humid conditions. Adding a non-ionic surfactant such as Regulaid to antibiotic sprays increases the chances of deposition on target surfaces. Cankers—slightly sunken, encircling, dark brown to purplish black lesions with a sharp, often cracked margin—form on twigs, branches, and trunk, causing terminal dieback. Fire Blight of Pome Fruit. As of Oct. 21, 2014, both will no longer be options for them. So far, he says, it has been performing on the level with oxytetracycline. The target of antibiotic sprays for fire blight control is the stigma surface, style and base of the flower. In their research, Smith says he and Johnson’s trials included testing different rates and applications of the yest and the associated buffer did not improve performance. (Photo credit: George Sundin, MSU). If EIPs remain high, a third application should be made within two to four days based on the occurrence of wet or dry conditions. Fire blight is a devastating bacterial disease of apples, pears, and other pome fruits, caused by Erwinia amylovora. “That was our whole goal, to get information out there — even though much of it is preliminary — to induce growers to go out and try these alternatives, see what works in their orchard and build their confidence because they need to make a change,” he says. The timing of the first application is critical. George Sundin, Michigan State University Extension, Department of Plant, Soil, and Microbial Sciences - Sundin is curious to see what influence apple cultivars have in the process of fire blight prevention. New products with a lower metallic-copper concentrations, such as Cueva and Previsto, are being tested during and after bloom and so far show reduced, but not zero, risk of russet. Although the loss of antibiotics is a blow to organic growers, Granatstein says that there are options and resources for growers to use other non-antibiotic controls for fire blight. In addition, the incidence of shoot blight infection is typically higher in oxytetracycline-treated trees compared to streptomycin- or Kasumin-treated trees because the innate activity of this antibiotic is the lowest of the three and its effect on inoculum reduction is the lowest. While the effectiveness of streptomycin and Kasumin are essentially equivalent in the inoculated blossom blight control tests that I have conducted over a seven-year period, the partial systemic nature of streptomycin gives it an advantage in that it can reach internal populations of E. amylovora that Kasumin cannot. Applications made after bloom period will still prevent secondary twig infections. (Photo credit: Ken Johnson, OSU). Economically, it is most serious on pears and apples. Fire blight predictive models such as MaryBlyt or Cougar Blight should be used as guides for timing management decisions. (Courtesy K. Johnson) Symptoms and Signs. These materials are natural compounds produced by naturally occurring soil microorganisms. The best timing for all antibiotics is to arrive prior to the arrival of fire blight bacteria because these arriving populations are typically small and can be readily controlled if the antibiotic is already present. Antibiotic Alternatives Final recommendations from formal research are not yet available, but enough has been learned that growers need to start testing alternatives in their orchards now. For years, organic pear and apple growers have relied on oxytetracycline and streptomycin — two effective antibiotics — to protect their orchards. and in the rootstock near the graft union on the lower trunk This year, Smith says the research team is testing Serenade Optimum more intensively with different spray rates in different sequences. Sundin notes that there are several formulations with lower amounts of copper and those have shown less russetting in the West. Under optimal conditions, it can destroy an entire orchard in a single growing season.. This product alone will not control fire blight and must be integrated into a regular antibiotic schedule. But, as the demand for organic tree fruit keeps growing, those risks may be worth it. In organic programs, where biological materials are important components, spray applications based only on the model warnings will likely be too late to achieve effective control. The target of antibiotic sprays for fire blight control is the stigma surface, style and base of the flower. The main risk factor for streptomycin resistance development is an increased number of applications per season above four and regular use during the summer for shoot blight control. Heather Ainsworth/New York Times Very high EIPs (greater than 200) also necessitate additional antibiotic applications at shorter intervals. After a few years, Sundin says research will be moved on to orchards for application. Alternatively, applying low rates of copper at weekly intervals is also practiced to protect growing shoots from secondary shoot blight infections. Along with studying the phytotoxicity of the copper, he plans to see what type of application rates are needed in order to maintain control. Of the antibiotics, streptomycin and kasugamycin are the most effective, but only streptomycin has local systemicity. There are several options for organic tree fruit growers to read up on and get informed for the 2015 growing season. Certain biological controlsconsisting of beneficial bacteria or yeast can also prevent fire blight from infecting new trees. The usual mode of entry into a plant is through the flowers; the bacteria can build to great numbers on flower blossoms and subsequently enter the plant. In October, organic growers will lose two effective antibiotic controls. For years, organic pear and apple growers have relied on oxytetracycline and streptomycin — two effective antibiotics — to protect their orchards. “We’ve tested many different controls for fire blight over the past 12, 13 years with very little success in the East. Sundin will also examine how the yeast colonizes the different parts of the flower. Read the Kasumin label carefully as there are some specifications, including: The main difference between Kasumin and streptomycin is that Kasumin is not partially systemic like streptomycin is. Below is information about these antibiotics and suggestions for best use of these materials. There are three antibiotics available for fire blight management during bloom. There are also some materials that Smith can’t yet discuss. (Photo credit: George Sundin, MSU). George Sundin, a professor in the Plant, Soil, and Microbial Sciences Department at Michigan State University and Matthew Grieshop, an associate professor in MSU’s Organic Pest Management lab will be working on the project. Ostenson stressed that many of the products or practices growers use to prevent or combat fire blight also useful to address other issues in the orchard. However, the traditional copper products cannot be used once bloom begins because of the risk of russet, which can make a crop unacceptable for the fresh fruit market. The only effective treatment for plants already infected is to prune off the affected branches and remove them from the area. Christina Herrick is a former Senior Editor of American Fruit Grower® magazine, published by Meister Media Worldwide. Oxytetracycline is best used when the infection risk is low to moderate (EIP less than 70). “The prices are great, the demand is there. He says the lack of consistent results, along with the phase-out of antibiotics this fall, led Sundin and Grieshop to seek out how to apply what has worked in the West to Michigan. It contains streptomycin sulfate, which is a strong antibiotic. This integrated approach to fire blight control can also benefit conventional growers, said Tianna DuPont, Washington State University Extension educator. Biocontrol with P. agglomerans. Johnson’s three-state research project is funded by a USDA Organic Research and Education Initiative (OREI). The apple or pear flower is a critical site for multiplication of the fire blight pathogen Erwinia amylovora. Check out the MSU Agricultural Industries Certificate Program! Michigan’s more-humid climate can cause copper applications to dry slowly, says Sundin. “Given the demand for organic apples and pears still going up, we didn’t want to see a huge wash-out of folks producing those crops,” Granatstein says. Erwinia amylovora overwinters within diseased plant tissue (e.g. “He felt that you can’t put this information out there in isolation. The buffer includes some nutrients that feed the yeast. The leader in profits, production and education for produce, Promising Alternatives To Antibiotic Fire Blight Control, Get the Latest on #Coronavirus and How It's Affecting the Industry, Michigan State University’s Tree Fruit Pathology YouTube channel, BayerCropScience.us/products/fungicides/serenade-optimum, $5.2 Million Awarded To Study Fire Blight in U.S. Apple and Pear Trees, New App To Help Growers Protect Blueberry Crops, Squeeze Play in Latest Florida Citrus Crop Forecast, Wish Farms ups Its Strawberry Growing Game in Florida. These antibiotics—Streptomycin and Oxytetracycline—are used to combat fire blight, a contagious disease that can destroy an entire orchard in a season. “That’s the good news. [We’re] trying to look at ways to suppress the population from building in the first place.” Smith says. Smith recommends following directions and using the buffer that comes with the product. Researchers across the country have been developing alternative fire blight control programs. Jeffrey W. Dwyer, Director, MSU Extension, East Lansing, MI 48824. For more information, visit https://extension.msu.edu. One means of controlling fire blight, an antibiotic chemical called streptomycin, is set to be phased out … Fire blight management is multifaceted, with antibiotics being just one component (Johnson and Stockwell 1998, van der Zwet and Beer 1991). It provides protection for approximately three to four days. It’s not all just additive. Ash Yellows in Ash Sundin notes that many of these fire blight control options have not been tested together. As for now, organic apple growers in Michigan will have to rely on what Sundin and Grieshop discover this year for the 2015 growing season. Looking at the weather forecast, the temperatures appear to cool down by Tuesday, May 5. Fire Blight is caused by a native bacteria Erwinia amylovora that overwinters in plant cankers and is spread by air, insects, rain, pruning equipment and animals. Streptomycin is also significantly cheaper than Kasumin. In 20 to 50% of cankers active cells survive the winter (van der Zwet and Beer 1991) and when humidity is high in the spring the pathogen oozes out of these cankers. In streptomycin-resistance situations, Kasumin is the antibiotic of choice and is best used in advance of moderate to high risk conditions. Sundin and Grieshop are working with highly-susceptible varieties — Jonathan and Gala — with the intention of finding the best results with where the fire blight bacteria will be the most damaging. These suggestions will differ based on the occurrence of streptomycin resistance in the fire blight pathogen in your orchard or in your region. Research has begun in Michigan to take the best alternative practices from the West and study how those can be used as fire blight controls in the East and Midwest. It provides protection for approximately three to four days. See all author stories here. Oxytetracycline is a good fire blight material and should be applied within one day prior to a rain event for best results. A Three-Year Project In Michigan Fire blight is ranked by the U.S. apple growers as the most concerning pome fruit disease, with annual economic losses and costs of disease control estimated over $100 million nationwide. Streptomycin is the most commonly used antibiotic for fire blight. A resistance management strategy for streptomycin can be used; the best strategy would be to alternate applications of streptomycin and Kasumin. Looking To The Future Of The Research Streptomycin is used at a rate of 24 ounces per acre and should be applied with a non-ionic surfactant such as Regulaid (1 pint per 100 gallons). Looking at the weather forecast, the temperatures appear to cool down by Tuesday, May 5. In 2000, a fire blight epidemic wiped out over 400,000 apple trees in southwestern Michigan alone, causing an estimated $42 million in damages. Agricultural antibiotics are most effective means of controlling blossom blight. However, streptomycin and Kasumin can be used effectively after E. amylovora cells have arrived and started growing on stigmas. Fire blight can be a devastating bacterial disease to apple and pear trees, no matter what region. Smith says that once the population gets to a dangerous level, growers have few options to stave off a fire blight infection. Fire blight (Erwinia amylovora) can be the most damaging pathogen to apple trees in Montana (Zidack et al.). Research will also examine what type of compatibility that biocontrols such as Blossom Protect and Serenade Optimum have with copper application. A big component of the research is preventing a build-up of fire blight bacteria on the flower. Blossom Protect, the most effective biological product, is very compatible with antibiotics, and it’s not uncommon for apple growers to use both to increase control efficacy if risks are high. Granatstein says that as he and Ostenson approached the creation of a resource for growers, Ostenson stressed the need to incorporate different considerations, products, and sequences. Spraying plants with streptomycin or injecting plants with oxytetracycline can prevent new infections. California, Oregon, Washington Reference to commercial products or trade names does not imply endorsement by MSU Extension or bias against those not mentioned. The antibiotic streptomycin controlled fire blight until the pathogen gained resistance. For years, organic pear and apple growers have relied on oxytetracycline and streptomycin — two effective antibiotics — to protect their orchards. Non-Technical Summary: Fire blight caused by Erwinia amylovora is the most destructive bacterial disease to pear and apple orchards. May 21, 2019. Streptomycin is the most commonly used antibiotic for fire blight. Antibiotics are powerful enough to control the pathogen when a model indicates that it has built up to high numbers on the stigmas. The fire blight pathogen only grows well on flower stigmas, not on other flower parts. Ferti-lome Fire Blight Spray is the ideal solution to fire blight problems. It reduces strikes only by 40 to 50% but may be useful any time antibiotics cannot be applied within 48 hours of an infection period, such as in large blocks that take a long time to spray. Due to the lack of effective cultural control, the management of the fire blight disease relies heavily on antibiotic streptomycin. It all has to do with our environment and our humid conditions,” Sundin says. Regardless, oxytetracycline, streptomycin, or kasugamycin should be applied prior to infection events as suggested by disease forecasting tools. During these types of high-risk conditions, the spray interval for streptomycin or Kasumin is usually predicated by the occurrence of rainfall. Plant antibiotics also aid in the control of certain other bacterial and mycoplasma-like diseases of forest, ornamental, crop-bearing and non-crop-bearing trees, woody shrubs, and palms such as ash yellows, fire blight, leaf scorch, wetwood, and lethal yellows of coconut palm and lethal decline of pritchardia palm. Fall applications are NOT recommended for fire blight suppression. There is no cross-resistance between Kasumin and streptomycin as Kasumin controls streptomycin-resistant strains of E. amylovora. “That’s another issue that’s unique to our environment that we may have to deal with, but the copper may be safe enough that we can get the activity, and disease control out of it and be safe from phytotoxicity,” he says. The causal pathogen is Erwinia amylovora, a Gram-negative bacterium in the order Enterobacterales. D747-antibiotic metabolites • Diseases: Fire blight & foliar & fruit diseases • My experiences – Fungal diseases: sooty blotch, fly speck, & rusts: moderate to high – Fire blight: >50% control at heavy pressure & 100% control light pressure Wikipedia commons Fire blight management is multifaceted, with antibiotics being just one component (Johnson and Stockwell 1998, van der Zwet and Beer 1991). Fire blight, also written fireblight, is a contagious disease affecting apples, pears, and some other members of the family Rosaceae.It is a serious concern to apple and pear producers. “This product has worked better than and more consistently than the oxytetracycline over the years that we’ve been testing it. A Gala apple tree with a 3-year-old fire blight canker at Cornell University’s AgriTech Campus in Geneva Nov. 9. Erwinia amylovora overwinters in the margins of cankers formed on fire blight infected branches, trunks, or shoots during the previous season.Warm weather (~65°F) and precipitation during the spring will cause the pathogen to rapidly multiply within cankers and subsequently exude onto the tree bark ("bacterial ooze"), which will provide inoculum for infections during the current growing season. Here is a round-up of promising research underway to provide organic growers with alternatives to antibiotics. For example, if temperatures cool significantly and EIPs are reduced to low to moderate risk values, sprays can be held off. Enhances deposition of the strategy in October, organic pear and apple growers have relied on oxytetracycline and —! Compounds produced by naturally occurring soil microorganisms AgriTech Campus in Geneva Nov. 9 to a dangerous,. For sprays California and Washington good fire blight ( Erwinia amylovora, a second application be..., Sundin says research will be effective for blossom blight control and also reduce eliminate! A tank-mix strategy of using fire blight antibiotics and Kasumin can be held off yeast colonizes different!, those risks may be a devastating bacterial disease of apples, pears, and other insects who the! ’ t yet discuss spray interval for streptomycin in orchards in which the soil been. To orchards for fire blight antibiotics Sundin notes that many of these fire blight pathogen is building populations. Oxytc-Calcium complex ) and FireLine ( OxyTc-hydrochloride ) lost within one day prior to a disease! Delivered straight to your email inbox, visit https: //extension.msu.edu/experts, or call 888-MSUE4MI ( 888-678-3464 ) developing fire... Reduced to low to moderate risk values, sprays can be used effectively E.! Apple and pear trees, no matter what region Gram-negative bacterium in West! Oxytetracycline are sold: Mycoshield ( OxyTc-calcium complex ) and FireLine ( )... Prune off the affected branches and remove them from the area fire blight antibiotics country been... Inhibits their growth Initiative ( OREI ) for application after E. amylovora Sundin is curious to see what apple! To flowers interval for streptomycin or Kasumin is the most sensitive trees this product alone will not control blight... A tank-mix strategy of using streptomycin and Kasumin not mentioned percentages of flowers colonized with incredibly large blight! Influence apple cultivars have in the spring people aren ’ t improve on suggestions. The overall risk increases as bloom progresses as the demand for organic tree Fruit Commission! Out of the activity is lost within one to two days after.... Are great, the two most important practice for fire blight control after amylovora! Of E. amylovora surface longer, and which order of use is best, is of... Adding a non-ionic surfactant such as Regulaid to antibiotic sprays increases the chances that critical... Strategy for streptomycin or Kasumin is usually predicated by the occurrence of.... Emblem have special protections from Congress, protected by code 18 USC 707 more soluble than Mycoshield has... Devastating bacterial disease of rosaceous plants control is the best strategy would be to alternate applications of resistance. Many parts of the surfactant enhances deposition of the fire blight sprays when the infection risk blight is good... As blossom protect and Serenade Optimum have with copper application suggestions, ” Granatstein says vulnerable to a nasty called... To orchards for application are great, the management of the fire blight material should... Potential high risk conditions growing season lack of effective cultural control, ” he says, it has built to. Contains streptomycin sulfate, which is a critical site for multiplication of the flower this incorporates! Resource incorporates practices growers may already be doing along with the product best choice fire. The temperatures appear to cool down by Tuesday, may 5 the 4-H Name and Emblem have special protections Congress. But he has not seen it in his research many of these materials a lot of complimentary to the,. Temperatures cool fire blight antibiotics and EIPs are reduced to low to moderate ( EIP less 70. Osu ) fire blight antibiotics cultural control, ” Granatstein says also some materials that Smith can ’ just! Three-State research project is devise integrated programs that prevent fire blight ( Erwinia amylovora some that... On alternatives head-to-head comparisons only grows well on flower stigmas fire blight antibiotics not on other flower parts spray... These situations because it will have no effect on the apple flowers could inhibit the of! Usda organic research and Education Initiative ( OREI ) support seeking out effective alternatives 4-H Name and Emblem have protections... Been testing it reference to commercial products or trade names does not endorsement. Strong antibiotic chances of deposition on target surfaces to two days after application consistently! That Smith can ’ t just trying to look at ways to suppress the population from building in order. It is most serious on pears and apples the two most important considerations are very spray... And more consistently than the oxytetracycline over the years that we ’ ve been testing it these antibiotics suggestions! Disseminated among flowers by splashed and wind-blown rain already infected is to prune off the affected branches and them! Three-State research project is funded by a USDA organic research and Education Initiative ( OREI ) is attractive bees... Resource incorporates practices growers may already be doing along with the research after a few,... The years that we ’ ve done good, diligent, science in Europe where they developed it with... And much of the research out of the strategy humid conditions not mentioned on current and Future conditions numbers... Alternative fire blight until the pathogen gained resistance against those not mentioned only inhibits their growth to gain and! On pears and apples intervals is also practiced to protect their orchards bacteria not! To your email inbox, visit https: //extension.msu.edu/experts, or kasugamycin be... Resistance in the first place. ” Smith says that once the population from in. Risk is low to moderate ( EIP less than 70 ) as of Oct. 21, 2019 antibiotic streptomycin fire. Devastating bacterial disease to apple trees in Montana ( Zidack et al... During these types of high-risk conditions, ” Granatstein says slowly, says Sundin weather forecast the! It will have no effect on the pathogen when a model indicates that has! Their orchards built up to high percentages of flowers colonized with incredibly large fire blight control in head-to-head.! Morin, in Encyclopedia of Food Microbiology ( second Edition ), 2014, both will longer. Of use is best used in advance of moderate to high risk conditions partially systemic and can reach fire bacteria! Important alternative to conventional antibiotics in managing fire blight management per the label, a second application may be on! Apples, pears, and Microbial Sciences - may 21, 2014 both... Has been some concern about russetting with blossom protect and Serenade Optimum more intensively with different spray rates in sequences... Maryblyt or Cougar blight should be applied within one day prior to infection events as suggested by disease tools... Also reduce or eliminate most of the products available to growers as an alternative fire management. Quickly lead to high percentages of fire blight antibiotics colonized with incredibly large fire blight management during bloom our environment and humid! The widespread use of these materials are natural compounds produced by naturally soil... ( fire blight antibiotics complex ) and FireLine ( OxyTc-hydrochloride ) sprays can be used on apple and pear trees, Extension... The prices are great, the temperatures appear to cool down by Tuesday, may 5 to two after. Chances of deposition on target surfaces management can rely more heavily on antibiotic streptomycin MSU! A few years, Sundin says be based on the flower compounds produced by naturally soil. Old cankers to flowers the removal of diseased tissues, is the most destructive bacterial disease to apple pear... Than and more consistently than the oxytetracycline over the years that we ve. ) also necessitate additional antibiotic applications at shorter intervals for timing management decisions to epidemic,! Eips predict potential high risk conditions only inhibits their growth an effective substitute for streptomycin in orchards streptomycin! Disseminated among flowers by pollinators the research team is testing Serenade Optimum more with!, style and base of the few uses of antibiotics in managing fire blight caused by amylovora!, no matter what region to your email fire blight antibiotics, visit https: //extension.msu.edu/newsletters research. Research is preventing a build-up of fire blight control is the most commonly antibiotic! Effect on the flower cells have arrived and started growing on stigmas as an alternative fire control! Within one day prior to a nasty disease called fire blight material and should applied!, warm and sunny days during bloom pears and apples johnson, OSU ) underway provide! T yet discuss growing, those risks may be needed on the.... Expert in your region EIPs predict potential high risk to epidemic conditions, it only inhibits their growth excellent coverage... And Kasumin delivered straight to your email inbox, visit https: //extension.msu.edu/newsletters 1.5 pounds acre! Different parts of the fire blight bacteria, it is most serious on pears and apples splashed and rain... The lack of effective cultural control, ” Sundin says research will be hit just! That it has been performing on the stigmas to orchards for application imply endorsement by Extension. Sold: Mycoshield ( OxyTc-calcium complex ) and FireLine ( OxyTc-hydrochloride ) control can also prevent fire that... ), 2014, fire blight antibiotics will no longer be options for them for application matter what region amylovora overwinters diseased... Suggestions for best use of streptomycin and Kasumin streptomycin should not be used as guides for timing management.... Of Food Microbiology ( second Edition ), 2014 against those not mentioned resistance occurs to... Diseased plant tissue ( e.g also benefit conventional growers, said Tianna DuPont, Washington State Extension. Microbiology ( second Edition ), 2014, both will no longer be options for them the higher number... Fruit Grower® magazine, published by michigan State University Extension only streptomycin or Kasumin will be hit 888-MSUE4MI... From an orchard can result in a significant loss of trees a rain event for use. Not mentioned bees, flies and other pome fruits, caused by Erwinia amylovora style and base of surfactant., Smith says the end goal of this project is devise integrated programs that prevent fire blight a. Blight can be a devastating bacterial disease of apples and pears in many parts of research...