In 2012, China’s General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ) suspended importation of apples produced in Washington State due to repeated incursion of diseases. The red and golden delicious apples purchased were afflicted with Sphaeropsis rot, bull’s-eye rot and speck rot. It wasn’t until this year, just last month, after intensive work with the USDA Animal and Plant Health Inspection Services (APHIS), that China reinstated importation of these apples.
USDA APHIS and the Foreign Agricultural Service have been working closely with apple industry stakeholders over the past couple of years to develop safeguards to address China’s concerns regarding apple pests and diseases. Some additional safeguards now in place include cold storage of apples and visual inspection by trained and knowledgeable personnel prior to shipping to ensure the health and pest-free status of apples being exported. The Chinese market for Washington apples was valued at $6.5 million in 2011, the ban dealt a major blow to the industry, this is why efforts are ongoing to maintain safe market access for Washington grown and other U.S. apples into China.
Four species of fungus in the genus Neofabraea are known to cause Bull’s eye rot; three species, N. alba, N. perennans, and a Neofabraea sp., have been reported in the Pacific Northwest. Bull’s eye rot lesion is circular, flat to slightly sunken and appears light brown to dark brown with a lighter brown to tan center. Bull’s eye rot occurs on both apples and pears in the U.S. Pacific Northwest. In Washington State, Bull’s eye rot is more commonly seen on Golden Delicious, particularly on apples from orchards with perennial canker problems on trees.
Speck rot, a postharvest fruit rot disease of apples, is caused by the fungus Phacidiopycnis washingtonensis. Decayed areas appear light brown to dark brown or occasionally black. Brown to black specks with white to light tan centers may appear around the lenticels.
Sphaeropsis rot is a newly reported postharvest fruit rot disease of apple and pear. The primary symptoms of Sphaeropsis rot are stem-end rot and calyx-end rot originating from infections at the stem and calyx of fruit, respectively. The decayed tissue is firm or spongy, and the decayed areas appear brown. The internal decayed flesh appears brown. Sphaeropsis pyriputrescens Xiao & J. D. Rogers is the causal agent of Sphaeropsis rot.
The USDA continues to act as a strong and effective partner and advocate in the international agricultural marketplace. APHIS works to ensure that agricultural products coming into the U.S. meet entry requirements and stringent standards excluding pests and disease. While this is playing out on an international stage, we all have to be aware how we can prevent the spread of pests and disease at home, this includes not moving lumber or wood among states, using appropriate and responsible methods to control pests on our landscapes, buying and planting local, native, disease resistant plants, educating ourselves and advocating for integrated pest management, invasive species control and native vegetation. For more information on plan healthcare and disease management, contact your arborist and visit https://www.savatree.com/tree-disease-treatment.html.
