ARS 

Collections

United States 

Department of 

Agriculture

Agricultural 

Research 

Service

Program Aid 2024

September 2009

ARS maintains hundreds of scientific collections that serve as 

definitive resources for agricultural research, germplasm for crop 

improvement, the identification of invasive species, and the documentation of global biodiversity. They include culture (living organisms), specimen-based (preserved), and non-organism (chemical or 

molecular reagent) collections. 

ARS collections support individual research projects, but they also 

serve as core references that are critical to the continuity of specific 

scientific disciplines. Collections are housed throughout the Nation 

and around the globe.

1
In general, the size, scope, and fiscal support for collections are 

strongly associated with their roles and objectives. 

Research Collection

•	 Assembled by individual research units to assist in-house

ARS research. 

•	 Often small and are not intended for widespread distribution.

Scientists usually provide access to these collections upon request 

from other researchers. 

Core Systematic or Reference Collection

•	 Maintained over decades for systematic and taxonomic research,

and critical to the continuity of specific scientific disciplines. 

•	 Samples distributed worldwide to support systematic and

	 taxonomic research.

National Genetic Resource Collection

•	 Maintained over decades to preserve essential genetic materials

(species, varieties, lines) for research and genetic improvement. 

•	 Samples distributed worldwide.

2
Smaller, research-based collections are generally managed by the 

individual scientist or team working on the research project associated 

with the collection. However, larger collections such as the genebanks 

of the National Plant Germplasm System have full-time curatorial 

staff working to acquire, preserve, analyze, document, distribute, and 

dispose of accessions. The majority of these collections have firmly 

established management practices through official policy and procedural guidelines governing access to and use of the collections.

3
ARS collections generally can be divided into the following 

15 categories: 

•	 Bacteria

•	 Fungi

•	 Nematodes

•	 Parasites and vertebrate protozoa

•	 Invertebrate protists

•	 Invertebrate viruses and cell cultures

•	 Plant viruses and viroids

•	 Vertebrate viruses

•	 Invertebrate germplasm

•	 Invertebrate systematics

•	 Vertebrate germplasm

•	 Plant genetic resources, including genetic stocks

•	 Natural resources

•	 Chemicals

•	 Molecular reagents

Within these categories, ARS collections vary in size, scope, and 

purpose. Highlights include the ARS Culture Collection in Peoria, 

Illinois; the USDA Nematode Collection and the U.S. National 

Parasite Collection in Beltsville, Maryland; and the genebanks of

the National Plant Germplasm System. 

Penicillia Nematodes Parasites Seeds

4
The ARS Culture Collection is the largest publicly accessible 

collection of microorganisms in the world. This broad collection of 

bacteria and fungi, maintained in Peoria, Illinois, is officially registered with the World Data Center for Microorganisms and serves as

an international reference of microbial germplasm for agriculture, 

biotechnology, and medicine. Holdings are accessible to researchers 

worldwide through an online database and also support key ARS research projects in microbial genomics and bioprocessing at Peoria’s 

National Center for Agricultural Utilization Research. 

Accessions in the ARS Culture Collection

•	 19,000 strains of bacteria

•	 60,000 strains of fungi

•	 6,000 patent cultures

Andrew J. Moyer increased previous

yields of penicillin tenfold.

Microbiologist Cletus Kurtzman retrieves

yeasts for molecular probe development.

5
The USDA Nematology Laboratory in Beltsville, Maryland, maintains the USDA Nematode Collection, the Nation’s premier repository of fixed specimens of plant and insect nematodes. Established in

1960, the collection is recognized as one of the world’s largest and

most valuable resources for nematode research. The materials in the 

collection are used by researchers in Beltsville and around the world

for systematics research and identification of parasitic nematodes. 

Accessions in the USDA Nematode Collection

•	 40,000 nematode species

6
The National Rhizobium Germplasm Resource Collection, also 

in Beltsville, Maryland, is maintained by the Soybean Genomics and

Improvement Laboratory. Founded in 1913, the collection is used

for research, legume inoculation, bioremediation, and land reclamation. Accessions are listed in an online database and are distributed to 

researchers around the world. 

After Iraq’s Rhizobium collection was 

destroyed during recent armed conflict, the 

Beltsville collection provided the nitrogenfixing bacteria to help Iraqi scientists

reestablish this important agricultural 

resource. 

Accessions in the National Rhizobium

Germplasm Resource Collection

•	 5,000 specimens of rhizobia

•	 2,000 uncurated specimens

7
The National Plant Germplasm System (NPGS) is one of the largest and most important distributors of germplasm in the world. The 

system comprises more than 20 genebanks throughout the United

States, which conserve germplasm of grain, vegetables, sugar crops, 

oilseeds, fruits, nuts, beans, ornamentals, and various other crops. 

Some 13,134 species are represented by 513,166 accessions. These

resources provide the essential genetic materials to support research 

and genetic improvement of crops worldwide. The system is widely 

recognized as pivotal to global food security. 

Genebank resources are accessible online through the Germplasm 

Resources Information Network (GRIN) system, a database documenting accession numbers, locality data, associated vegetation, data 

on key agricultural traits, and other relevant information for each 

accession. GRIN makes germplasm materials available free of charge 

to researchers and breeders in search of genes for product quality and 

for resistance or tolerance to various pathogens and environmental 

stresses.

A few prominent collections within NPGS

•	 National Small Grains Collection

•	 USDA Soybean Germplasm Collection

•	 National Cotton Germplasm Collection

•	 U.S. Potato Genebank

•	 National Clonal Repository for Temperate

	 Fruit, Nut, and Specialty Crops

•	 Five Regional Plant Introduction Stations

8
Throughout ARS’s 53-year history, scientific collections have been

significant to the agricultural community, and it is difficult to overestimate their importance. Their value to agriculture and the economy 

becomes all the more apparent after a disease outbreak or other major incident affecting agriculture. Many times ARS collections have

identified invasive species or settled international trade disputes and 

quarantine issues. 

9
The USDA Nematode Collection has played a significant role in enhancing economic opportunities for agricultural producers. In 1970,

ARS scientists used samples from the collection to determine the 

source of a nematode pest problem threatening the potato economy 

of the Pacific Northwest, ultimately saving the industry. Similarly, in 

2000 the collection was used to prove that U.S. wheat exports were

free of a quarantined nematode and thus were safe for foreign nations 

to import. Millions of dollars were saved for the wheat industry.

10
A recent example highlighting the importance of smaller, researchoriented holdings involves ARS’s honey bee collection in Beltsville, 

Maryland. When colony collapse disorder (CCD), the phenomenon 

of unexplained bee losses, became widespread throughout the United

States in late 2006, preliminary research suggested that a new pathogen, the Israeli acute paralysis virus, was to blame. Some experts

hypothesized that the virus entered the country in 2005 when a ban

on Australian bee imports was lifted, coinciding with the onset of 

CCD. Therefore, they recommended that the ban be reinstated. 

Beltsville researchers studied samples from the bee collection dating

back to when the ban was still in effect. They found that the virus 

species had already been present in the United States for at least 2

years before the ban was lifted. Because of this finding, the ban was

not reinstated.

11
In an ongoing effort to combat an emerging, particularly virulent 

strain of wheat stem rust (Ug99), ARS scientists have been taking

advantage of the National Small Grains Collection, an assemblage 

of wheat and other germplasm with a variety of traits and genes. 

Dating back to 1897 and officially organized in 1948, the collection

is maintained in Aberdeen, Idaho. The collection has provided an 

abundance of diverse resources for scientists as they aim to safeguard 

the wheat supply from Ug99.

Ug99 was recently recognized as the most serious strain of rust to

emerge in more than 50 years; it threatens more than 70 percent of

worldwide wheat production. To date, the researchers associated with 

the collection have assisted screening and monitoring to determine 

the spread of the disease in eastern Africa and have supported the 

evaluation of existing wheat varieties for susceptibility to Ug99. The

collection also provides resources for the identification of resistance 

genes and their integration into new, more robust wheat cultivars. 

12
ARS takes primary responsibility for maintaining the Nation’s collections of plant, animal, arthropod, systematics, and parasite and 

microbial resources of importance to agriculture. Moreover, the

agency’s role as principal curator for scientific collections of interest 

to agriculture and the environment is expected to increase significantly in the future as support for curatorial activities at universities 

and private institutions continues to decline. 

For many reasons, the stewardship of Federal scientific collections

has been identified as a top priority for ARS. In the coming years, 

ARS will actively pursue the preservation and enhancement of its 

collections to promote their utility as definitive resources for agricultural research and protection of the Nation’s food supply. 

13
ARS Mission

The Agricultural Research Service conducts research to develop and 

transfer solutions to agricultural problems of high national priority 

and provides information access and dissemination to:

•	 ensure high quality, safe food and other agricultural products;

•	 assess the nutritional needs of Americans;

•	 sustain a competitive agricultural economy; and

•	 enhance the natural resource base and the environment, and

provide economic opportunities for rural citizens, communities, 

and society as a whole.

The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, 

national origin, age, disability, and where applicable, sex, marital

status, familial status, parental status, religion, sexual orientation,

genetic information, political beliefs, reprisal, or because all or part 

of an individual’s income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with 

disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact

USDA’s TARGET Center at (202) 720-2600 (voice and TDD). To

file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue SW, Washington,

DC, 20250-9410, or call (800) 795-3272 (voice) or (202) 720-6382

(TDD). USDA is an equal opportunity provider and employer.