Annette Kenney

Participant: PROMISE AGEP Research Symposium

Annette Kenney

Department: Agriculture, Food, and Resource Sciences

Institution: University of Maryland, Eastern Shore (UMES)

 

2019 ABSTRACT

Survival of E. coli in Manure-amended Certified Organic Soils and Transfer to Tomatoes, Radish, and Spinach in Maryland Eastern Shore

Annette Kenney¹, Pat Millner², Alda Pires³, Michele Jay-Russell⁴ and Fawzy Hashem¹

¹Department of Agriculture, Food, and Resource Sciences, University of Maryland Eastern Shore, Princess Anne, MD, ²USDA-ARS, Beltsville Agriculture Research Center, Beltsville, MD, ³School of Veterinary Medicine, University of California Davis, Davis, CA, and ⁴Western Center for Food Safety, University of California Davis, Davis, CA

 

Organic fresh produce growers often use raw animal manure to improve and maintain soil quality and productivity. However, untreated, raw,   animal manure used as soil amendment can result in contamination of fresh produce by pathogenic microorganisms that can cause foodborne illnesses. Concerns about potential produce contamination by foodborne illness pathogens, led the National Organic Program to require a 90-day wait time between soil amendment application and harvest for produce not in direct contact with soil. For produce in direct contact with raw manure-amended soils, a 120-day wait time is stipulated. In this study, the survival of E. coli in organic soils amended with raw animal manure were inoculated with a three-strain cocktail of non-pathogenic, rifampicin-resistant E. coli (rif-EC) at 6 log CFU/ml (1-L per 2m² plot). A randomized complete block design with 4 replications and 4 treatments: horse manure (HM), dairy manure (DM), poultry litter (PL) and unamended (UnA), were established at the University of Maryland Eastern Shore Research Farm. Throughout two growing seasons (May-December 2017 and May-December 2018) soils were analyzed on days 0, 30, 60, 90, and 120 pre- and post-inoculation. The EC survival was higher and more persistent in the PL-amended soils, than other manures. The results distinctive to certified-NOP soils and FSMA regulations will support risk based assessments for development of application-to-harvest wait-time intervals for fresh produce safety.

 

SELECTED LIST OF PRESENTATIONS AND PUBLICATIONS

1. American Society of Horticulture Science Undergraduate Poster Presentation 1^st Award
2. 1890 ARD and USDA-ARS Food Safety Symposium Graduate Poster Presentation 2^nd Award
3. Farm Credit Business Pitch 3^rd Award