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Penn State Extension has planned ten educational meetings for commercial tree fruit growers this spring.
For commercial tree fruit growers in Pennsylvania, who feel they have been experiencing Rapid Apple Decline in their orchard, we are requesting their assistance by completing a questionnaire to help us further study the problem.
Due to the presence of green tip on early varieties of apples combined with rain and mild temperatures occurring this week, we are in our first apple scab infection period for 2017.
Penn State Extension held nine regional educational meetings for commercial tree fruit growers this winter.
Consider applying dormant sprays soon to manage fungal and bacterial diseases this season.
The updated Penn State Extension Spray Record-Keeping Spreadsheet for apples, pears, peaches, and cherries is now available from Penn State Extension.
Depending on your location, the warm weather over the last few weeks may have pushed some fruit trees along. For disease management, consider applying dormant copper and urea sprays soon.
Moldy core is characterized by the growth of fungus mycelium within the apple fruit seed cavity, without penetration into the flesh of the fruit.
I spent most of the summer writing a review paper on apple rootstocks and came across quite a bit of information that might be of interest to commercial fruit growers.
There is a mystery surrounding rapid apple decline/sudden apple decline of young, dwarf apple trees. For the last several years, there have been many reports in Pennsylvania and, most recently, in the Northeast and states south about unusual sudden decline of young, dwarf apple trees.
Sanitation is the best offense for disease management, especially when it comes to canker removal.
Growers can get a jump on disease management for the 2017 season this fall. This month’s article will be a review of tips to manage apple scab, peach leaf curl, and cherry leaf spot.
There have been many reports of bitter rot on apple while fruit are being harvested. With Mother Nature recently dumping a ton of rain, which will have washed off any plant protection materials, growers are encouraged to apply protectants to apple varieties that have yet to be harvested. Tips for identification and late season management are discussed.
Management strategies are discussed for mitigating the postharvest disease Rhizopus rot on peaches and nectarines.
A review of managing pre- and postharvest apple fruit rots is discussed. Alternative rot management strategies are included.
With peach season in full swing, a review of management strategies for controlling brown rot is discussed.
The latest information that growers need to know for apple scab, fire blight, sooty blotch and flyspeck, rots, bacterial spot, and cherry leaf spot.
The Tree Fruit Pathology Lab at FREC is seeking fire blight samples again this season from around the state of Pennsylvania in commercial orchards and home landscapes for evaluation for antibiotic-resistant strains of the bacteria and other projects. If you have fire blight present in your orchard/yard, please contact Dr. Kari Peter for instructions for sampling.
We all get a little rusty as we get older, but one thing that we don’t want to see getting rusty is our brambles. There are several rust diseases that affect brambles. I’m just going to focus on orange rust, which is the most important rust disease in the northeast. We are definitely seeing a bit of orange rust this year, with the cool wet springs. You’ll see this disease on blackberries, black raspberries and purple raspberries. Orange rust does not affect red raspberries.
We continue to observe a strong presence of codling moth adults in pheromone traps placed in commercial apple orchards. Despite the codling moth developmental model suggesting the end of the codling moth egg hatch period (95% eggs hatched by June 25), the presence of moths in the traps in the next few weeks still warrants extended management activities.
A new smartphone application, called MyIPM-NED, was developed to promote integrated disease management for apples, pears, cherries, and cranberries and is available for free for Android and iOS devices. These apps are also able to be used on tablets, as well.
After a dry April, rain has crept into the forecast making conditions ideal for apple scab, fire blight, and cherry leaf spot. Other diseases to keep an eye for management are powdery mildew and bacterial spot. For those who had their stone fruit crop frozen out in April, disease management is still needed. Disease infection periods are being posted for regions in Pennsylvania and Maryland.
Strawberries are blooming, the rain is falling and it’s warming into the 60’s and 70’s—and as a plant pathologist, all I see is Botrytis spores dancing about the farm. We have already started to see Botrytis popping up on stem tissue and flower petals. Scouting for the pathogen in your fields will help inform you whether you need to spray.
Unusually warm weather in March, despite relatively colder conditions in early April, pushed the development of most insect pests well ahead of a routine timetable.
The recent winter-like conditions do not kill scab spores and the spores continue to further mature and release. If the weather forecast comes to fruition, an apple scab infection event is predicted for April 7. If your trees have green tissue, recommendations for dealing with scab while managing cold injury are discussed.
All current conditions point to an early spring and tree fruit bloom. At Rock Springs we had first bloom on Methley plums and pink on peaches on Friday March 25th. Last year we observed the same growth stage on April 29th!
This article will help you manually determine infection periods for certain diseases (scab, fire blight, cherry leaf spot). Also included is a table listing coppers available to manage bacterial spot during cover sprays.
Since 1980 weather patterns such as rainfall quantity and duration, temperature and extreme weather events have become increasingly erratic.
Aprovia is a new fungicide (SDHI, FRAC group 7) available for pome fruit disease management. Due to crop safety concerns, BASF will be cancelling the pome fruit registration for Vivando.
Due to the presence of green tip on early varieties of apples combined with rain the last several days plus forecasted for the next two, we are in our first apple scab infection period for 2016. Protection is needed for vulnerable green tissue; a copper spray will be useful for trees not at green tip.
The first scab spores of the season have been detected; however, there is no scab infection risk until green tissue is present and there is an infection period. Since trees are pushing due to the warm weather the last several days, now is a good time to apply dormant copper sprays to manage diseases.
The past two winters have ramped up concerns about crown gall in Pennsylvania and other parts of the Northeast. Wine grape growers are discovering, many for the first time, the horrors of this disease and the extent of the damage it can cause in their vineyards. While there is reason for great concern, I would like to start out by saying that research efforts are generating extensive information on management of this disease, and there are new solutions from research in the pipeline.
When it comes to managing fire blight, the first line of defense is good sanitation, which is removing the overwintering source for the bacteria: cankers. Understanding what a canker is, being able to identify them in orchard, the importance of removal, and pruning strategies are discussed.
Although the earth is warming as a whole as a result of climate change, the weather is also becoming more variable resulting in early-winter cold snaps, winter thaws followed by extreme cold events, and early spring bloom followed by frosts.
Growers can get a jump on fungal and bacterial disease management for the 2016 season this fall. A review of tips to manage apple scab, fire blight, peach leaf curl, cherry leaf spot, bacterial canker, and fungal fruit rots are discussed.
The Penn State Extension Horticulture, Start Farming, and Pesticide Education Teams have produced three new videos on integrated pest management practices for sustainable establishment and management of apple orchards.
The biggest disease concern this time of year is keeping fruit free of rots as they are nearing the home stretch of the season. The recent bouts of rain and prolonged warm weather are ideal conditions for fruit rot issues.
With peach season in full swing, a review of management strategies for controlling brown rot is discussed.
There has been much confusion this season being able to tell the difference between bacterial spot disease and copper injury. This article will describe symptoms in detail, as well as offer guidance to avoid the pitfalls of using copper for disease control.
Make sure you know where apple scab overwinters, how to monitor and when it is most likely to appear. Penn State Tree Fruit Plant Pathologist Kari Peter provides some key points..
The extremely wet weather over the last month has triggered rot issues in both sweet and tart cherries. As a result of the volume of fungal spores flying around and the persistent warm wet conditions, peach and nectarine growers need to be on high alert as we are nearing the home stretch for harvest. Vigilant rot management strategies are critical this year to prevent brown rot (and other rots) during preharvest and postharvest. Management options, including organic strategies, are discussed. Conditions continue to be favorable for bacterial spot, necessitating shorter spray intervals for disease management.
Anthracnose (also called ripe rot) in blueberry, has been quite severe this year, especially in highly susceptible varieties such as Bluecrop, Bluetta, and Blueray.
Thanks to one of our growers we have been advised of a formula error in our spreadsheet.
The Tree Fruit Pathology Lab at FREC is seeking fire blight samples from around the state of Pennsylvania found in commercial orchards and home landscapes for evaluation for antibiotic-resistant strains of the bacteria and other projects.
The beginning of July usually marks a switch in our approach to control common insect pests in orchards.
Primary apple scab is finally over as of mid-June. Conditions have been ideal for canker blight: leftover fire blight cankers continue to grow and bacteria move within the tree to growing areas causing shoot blight. Conditions have been favorable lately for bacterial spot on peaches.
Conditions have been optimal for canker blight: leftover fire blight cankers continue to grow and bacteria move within the tree to growing areas causing shoot blight. Shoot blight is also occurring to those who experienced blossom blight, as well. Leafhoppers are active and will cause wounds in growing shoot tips, creating entry points for bacteria to enter. Pruning blighted areas and managing insects are the best methods for control.
Primary scab infection is still occurring and this week will prove to be another critical period for disease management. Fire blight infections are popping up in the region and more could be expected as a result of the weather conditions. Scouting is a must this week; however, do not prune during wet weather. Conditions are also favorable for cedar apple rust, cherry leaf spot, and bacterial spot infections.
The primary infection period for apple scab continues, although available spore numbers are decreasing. Growers should be scouting for fire blight infection thanks to the ideal conditions we have been experiencing throughout the month. In light of the hail some growers experienced this week, a reminder that diseases still need to be managed despite a damaged or minimal crop during the season. Going into June, growers need to be mindful about controlling for sooty blotch and flyspeck soon.
Based on weather station data, we had only low risk fruit rot events in both Pennsylvania and Maryland up until mid-May, when several warm rains soaked the region, leading to two to three dispersal events. There are likely more to come, which means that throughout the region, there is an increased risk leading up to harvest of strawberries, and bloom time for many fruit crops. Protection of these highly susceptible flowers and fruits is critical.
A band of strong storms blew through Pennsylvania and Maryland this afternoon. If you experienced hail, apply streptomycin to apple and pear trees within 24 hrs of the hail event to prevent trauma blight. More heavy thunderstorms are in the forecast until early Thursday. Please be on alert.
The rain occurring today could have the potential to produce an apple scab infection event if adequate leaf wetness hours are achieved. Growers are encouraged to monitor conditions in their orchards and spray accordingly to protect for apple scab. In addition, be mindful of rust: the cedar galls have made their appearance, making spores available to cause infection in apple trees.
If the rain in the forecast comes to fruition this weekend, be prepared for a major apple scab infection period for the region. Growers in northern PA still in bloom need to be vigilant for fire blight conditions this weekend and next week. Although many are past bloom in the region, we experienced fire blight conditions from May 5 – May 12 and growers should begin to scout for infections during the coming week. Be on alert for powdery mildew infections, thanks to the dry weather lately. Control measures are needed to manage bacterial spot on stone fruit.
A weather system moving East will be bringing rain Tuesday into Wednesday. At the same time we are experiencing the peak period for dispersal of mature scab spores. The predictive models indicate May 5 - 6, 2015 will be a scab infection period. Growers need to protect trees to prevent scab infection during this critical period.
All predictive models indicate a high risk for fire blight infection this week due to the high temperature, humidity, and chance of rain showers in the forecast. Growers should begin protecting blossoms with streptomycin on Monday. More strep applications will be needed as infection conditions persist.
Rain is in the forecast for Thursday and Friday. As a result, the prediction models indicate this will be a scab infection period -- and a big one since we’re reaching peak maturity with spore release. This weather will also be ideal for cedar apple rust infection. Growers are encouraged to have trees protected before the rain occurs. In addition, growers need to be on alert for next week since fire blight models indicate the week of May 4 may be an infection period.
May is the battleground month for disease management: growers need to be on alert for apple scab, fire blight, powdery mildew, rust, cherry leaf spot, brown rot, and bacterial spot infection conditions. Disease infection periods are now being posted for regions in Pennsylvania and Maryland.
Dr. Cassandra Swett started at University of Maryland, College Park as the new grape and small fruit pathologist in May 2014, with a split research and extension appointment. Her primary functions are to develop basic and applied information that improves management of grape and small fruit diseases, provide a resource to extension specialists and educators, and communicate information on disease management to producers.
Real time disease updates are now available for berry growers. "Follow" on line or via your smart phone!
The strawberry bloom has begun and it’s time for fruit rot protection. Our two main targets for bloom time protection of strawberries are gray mold/ Botrytis fruit rot (Botrytis cinerea), and, if you are growing susceptible varieties like Chandler, anthracnose fruit rot (Colletotrichum acutatum).
Scab infection period today, April 20, 2015, and predicted through Thursday. Rain most likely washed off all protection that was applied prior to the rain overnight and early this morning. Growers are encouraged to spray their trees to prevent scab infection. For growers in Maryland experiencing bloom, a streptomycin spray to protect open blossoms from fire blight is warranted.
We’re experiencing a scab infection period April 17. Warm, wet weather also is a threat for stone fruit blossoms that are open. Fungicides needed today to protect against scab and blossom blight caused by brown rot.
If not already completed, copper sprays are encouraged for fungal and bacterial disease control. Apple scab primary infection has kicked off this week.
The who, what, why, when, where, how and how much of everything you need to know about fire blight and its management in preparation for the 2015 season.
Dormant season urea and copper sprays are recommended for decreasing available populations of apple scab spores and fire blight bacteria in the orchard for the 2015 season.
Organic fruit growing in the Mid-Atlantic Region can be successful and profitable with careful study and planning. There are natural features in the Mid-Atlantic region that offer nearly ideal conditions for growing high quality organic fruit. Also, the market in this area for locally grown organic fruit far exceeds the current production capacity of existing organic fruit farms.
The Penn State Tree Fruit Pathology Program has established a Twitter account to be another tool for folks to receive updates, information, and interesting pictures. Please start following!
As folks are pruning their apple trees, the presence of the Nectria fungus is being reported. A weak fungus that attacks already compromised trees, growers are encouraged to prune out symptomatic tissue from trees to limit spread of the disease.
To reduce apple scab risk for next season, growers are encouraged to spray a fall application of urea as close to leaf drop as possible. Prune out fire blight strikes now while they are still visible on the tree to prevent cankers from overwintering. For those battling bacterial canker, copper applications are recommended since autumn is an optimal time for high bacterial populations. Additional disease management strategies are also discussed.
The fungi causing fruit rots can be quite stealth since spores will land on the fruit and cause symptoms after the fruit have been in storage. We have had excellent conditions for fruit rots this month with frequent rain and stretches of warm weather.
Management is discussed for controlling the physiological disorder necrotic leaf blotch, which is being reported throughout the area. Managing late season bacterial spot and rot diseases on stone fruit is also discussed. Disease infection periods to date for apple scab, fire blight, cedar apple rust and cherry leaf spot are included to help growers determine where control failures may have occurred this season.
Conditions so far this season have been excellent for many stone and pome fruit diseases. Sooty blotch/flyspeck treatment threshold has been reached and disease control is encouraged. In addition to SBFS, management strategies are covered for fire blight, apple scab, fruit rots, bacterial spot, cherry leaf spot, and powdery mildew.
I suppose I do not have to tell you that bacterial spot is a difficult disease to manage.
A toll-free hotline is available for growers in the region to receive seasonal updates about pest and pest management information. Laminated copies of the fungicide resistance management guidelines for scab, powdery mildew, brown rot, and peach scab are available for anyone who didn’t receive a copy during the spring twilight meetings this year.
The primary infection period for apple scab is over. If growers are experiencing apple scab at this time, control measures will be needed throughout the remainder of the growing season to keep the disease in check. An option for fire blight management is also discussed.
Fire blight is being reported throughout Pennsylvania and Maryland. Management strategies are discussed for dealing with active fire blight infections.
Storms occurring on May 22, 2014 in the eastern part of Pennsylvania produced hail, which was capable of causing damage to fruit trees. Growers in affected areas will want to consider applying a streptomycin spray within 24 hrs of the hail event to protect trees from fire blight.
The weather during May 2014 has provided excellent conditions favorable for disease. Disease control recommendations are covered for fire blight, apple scab, powdery mildew, rust, and bacterial spot on stone fruit. This is an updated version of the Disease Update posted on May 14, 2014.
Fire blight risk remains high through the week. When applying streptomycin, it is effective for 24 hrs before and 24 hrs after a rain event. Apple scab spore dispersal is peaking, and with the predicted rain events this week, we are in for a very rough, serious infection period. There is potential for secondary spread if fungicide protection earlier this year was less than adequate. The humid conditions are also optimal for mildew and rust infections.
The apple blossoms are open and conditions are soon to be optimal for fire blight infection. Keep an eye on the weather for favorable temperatures and moisture since forecasts indicate May 9th to 12th (and possibly beyond) to be an infection period. Blossoms need to be protected.
Apple scab spores continue to rapidly mature and be released. With the expected rainfall accumulations predicted for tonight to Wednesday night to be at least three inches, the stage could be set for a severe apple scab infection period. Growers are encouraged to apply a spray prior to rainfall, particularly to susceptible cultivars and areas known for high scab inoculum.
Early season apple disease management is primarily directed at controlling scab.
Apple scab spores continue to rapidly mature and discharge. Rain and thunderstorms are forecasted for Tuesday, April 22, 2014, and combined with temperatures in the upper 60s to low 70s, these are once again great conditions for scab infection. Apple cultivars with green tissue need to be protected.
Apple scab spores are rapidly maturing and beginning to discharge. Combined with the rain and temperatures in the 60s, these are great conditions for scab infection. Early season apple cultivars with green tissue need to be protected.
If not already completed, copper sprays are encouraged for fungal and bacterial disease control. Scab spores have not yet been released. Excellent resources are available for growers for resistance management this season.
There is a need to figure out novel disease management strategies necessary for staying one step ahead of postharvest decay pathogens. Evaluating wild apples for resistance to postharvest diseases, understanding fungi causing decay in storage, and finding alternatives for controlling rots are briefly discussed.
As you begin thinking about your IPM scouting program for the new season, consider the value of field guide for proper identification of orchard pests and beneficials. The Tree Fruit Field Guide to Insect, Mite, and Disease Pests and Natural Enemies of Eastern North America includes 500 color photos, actual size drawings of pests, over 20 pages of diagnostic keys.
The Orchard Spray Record-Keeping Spreadsheet has been updated and is available at the Penn State Tree Fruit Production website (http://extension.psu.edu/plants/tree-fruit). New features include the addition of FRAC codes and pages for supplying additional information required by processors.
A must-have investment for folks in the tree fruit business is the recently released Compendium of Apple and Pear Diseases and Pests, Second Edition. The first edition was published in 1990 and the second edition has evolved to be nearly double in size. My one word review of the second edition: awesome.
To reduce apple scab risk for next season, growers are encouraged to spray a fall application of urea as close to leaf drop as possible. Additional disease management strategies are also discussed.
General management techniques for reducing postharvest fruit rots are important considerations as we approach harvest season. Growers are encouraged to use the infection periods posted as a tool to understand disease issues encountered in the orchard during this season.
The weather conditions during the last several weeks have provided excellent conditions for bitter rot. Growers are encouraged to monitor their orchards and apply fungicides on a 10- to 14-day interval until harvest for effective disease control. The latest infection periods have been posted.
Sooty blotch/flyspeck infection period is underway and growers are encouraged to apply a cover spray. The latest infection periods have been posted, which include sooty blotch/flyspeck.
Bacterial spot of stone fruit (caused by Xanthomonas arboricola pv. pruni [Xap]) remains the most important bacterial disease of peach and nectarine in the eastern United States. We conducted a study in 2012 to monitor and identify populations of bacteria in stone fruit orchards, including bacteria resistant to the antibiotic oxytetracycline and to determine the current levels of oxytetracycline sensitivity in Xap populations. Of the 237 isolates tested, 99% and 81% grew in media amended with 5 and 10 mg/L oxytetracycline, respectively, while 25% and 22% of isolates grew in media amended with 15 and 20 mg/L and greater of oxytetracycline, respectively. Prudent use of this antibiotic is advised to prevent the loss of sensitivity.
The primary infection period for apple scab is nearing an end. Scab sources are still being sought in the region for fungicide resistance studies. Included is a thank you note to the attendees of the Spring Meetings.
Peach leaf curl is occurring throughout the region; effective control measures occur after leaf drop in the fall. Weather conditions are still excellent for fire blight; growers are encouraged to keep young, newly planted blooming trees protected. Apple scab sources are being sought in the region for fungicide resistance studies.
Weather conditions are optimal for bacterial spot on stone fruit. Fire blight infection conditions forecasted through May 26. Bacterial spot and cherry leaf spot infection periods are also now posted.
Fire blight infection conditions forecasted for May 17 - 22 are high. Infection periods for apple scab, fire blight, cedar apple rust, and powdery mildew are being posted.
Fire blight infection conditions forecasted for May 10 to 12 are to be moderate to high. Possible apple scab infection conditions continue through the weekend.
Bloom is well underway for apples and pears. Be alert since this is a susceptible time for fire blight when conditions are favorable. Primary scab infection is still an issue. Dry weather diseases can still be problematic.