Penn State Extension
Penn State Extension
Articles Spraying by the Numbers: Fungicide Resistance Management
Kari A. Peter, Ph.D., Alan R. Biggs
Growers can prevent resistance to fungicides by alternating chemicals by FRAC group also known as "spraying by the numbers." More
News There were many diseases affecting tree fruit growers in 2018. Sanitation will be very important while preparing for the 2019 season. More
Articles Apple Disease - Marssonina Blotch
Kari A. Peter, Ph.D.
Marssonina blotch, caused by Marssonina caronaria, is a foliar disease first identified in Pennsylvania in September 2017. More
Articles MIP – Exploración y Manejo de la Roña de la Manzana
Kari A. Peter, Ph.D., Montserrat Fonseca Estrada, Tianna Dupont
Asegúrese de saber dónde pasa el invierno la roña de manzana, cómo supervisarla y cuándo es más probable que aparezca. More
News The Tree Fruit Pathology Lab at the Fruit Research and Extension Center is seeking apples infected with the fungus causing bitter rot from around the state of Pennsylvania in commercial orchards. More
News Managing Fruit Rots This Season
07/26/2018
Fungicide re-applications are necessary since several inches of rain have fallen the last few days. Management considerations are discussed for mitigating pome and stone fruit rots. More
News Mid-Season Tree Fruit Disease Update
06/26/2018
The latest 2018 disease updates growers need to know for apple scab, fire blight, sooty blotch and flyspeck, bacterial spot, and cherry leaf spot. More
Articles Tree Fruit Disease Toolbox - Fungicide Resistance Management
Kari A. Peter, Ph.D.
Resistance has sometimes resulted in pest-management-program failures. Below are presented tactics to help delay resistance to fungicides. More
Articles Stone Fruit Disease - Rhizopus Rot
Kari A. Peter, Ph.D.
Rhizopus rot, caused by Rhizopus nigricans, can be very destructive to harvested fruit. More
Articles Apple Disease - Blossom End Rot
Kari A. Peter, Ph.D.
Blossom end rot of apple, is caused by various fungi (Sclerotinia sclerotiorum, Botrytis cinerea, Botrysphaeria obtusa) just before or during petal fall. More
News Fire blight symptoms are widespread throughout Pennsylvania and Maryland. Growers are encouraged to use Apogee or Kudos to shut down tree growth to limit the spread of the disease in orchards. More
News Conditions were incredibly optimal for many tree fruit diseases during the month of May. Management strategies for pome and stone fruit diseases are discussed. More
News Reports of fire blight infections have started to occur. The dos and don’ts of managing fire blight infections are discussed. More
News Trees need to be protected during wet conditions. The following are strategies for keeping diseases in check on apple and stone fruit during persistent rainy weather. More
News The forecast for May 15–18 indicates conditions will be favorable for apple scab and bacterial spot on peach infections. If infections occurred during bloom, fire blight symptoms could begin to appear this week. More
News Bloom is occurring in Pennsylvania apple growing regions—fire blight conditions continue, available mature apple scab spores are very high, and an apple scab infection event is predicted for May 10, 2018. More
News Severe fire blight and apple scab disease conditions are predicted for May 3–5, 2018! Protection is absolutely necessary! More
News May 3–5 could be potential infection periods for apple scab and fire blight. Brown rot infection conditions favorable for open peach blossoms this week. More
News Torino (FRAC Group U6) has a supplemental label to control powdery mildew on apples and cherries. More
News Preparing for the Fire Blight Season
04/24/2018
Management strategies are discussed for fire blight, as well as for other important tree fruit diseases occurring during the month of May. More
News Tight cluster is the time powdery mildew spores become active. April 24 – 25, 2018 is a predicted scab infection period; be sure trees are covered with protection. More
News April 15–16 is predicted to be a scab infection period due to green tip present and mature scab spores available. Copper applications recently applied will offer protection. More
News Guidelines are described for properly maintaining one’s weather station post season in preparation for the 2018 season. More
Articles Tree Fruit Diseases - Spring Control Strategies
Kari A. Peter, Ph.D.
May is the battleground month for disease management: be on alert for apple scab, fire blight, powdery mildew, rust, cherry leaf spot, brown rot, and bacterial spot infection conditions. More
Articles Orchard IPM - Apple Scab Scouting and Management
Kari A. Peter, Ph.D., Tianna DuPont
Make sure you know where apple scab overwinters, how to monitor, and when it is most likely to appear. More