Bean/Cowpea CRSP

Biodiversity and

Conservation Activities

James R. Steadman- University of Nebraska

MalawiMozambiqueSouth Africa

Tanzania

Costa RicaDominican RepublicEcuadorEl Salvador

GuatemalaHaiti

HondurasJamaica

Nicaragua

Latin America

and Caribbean

Project

BeninBurkina FasoCameroonGhana

NigerNigeriaSenegal

Zimbabwe

West Africa Project

East and Southern

Africa Project

•Development of improved germplasm and cultivars for common bean and cowpea. Biotic stresses emphasized

Bean/Cowpea CRSP priority over past 25 years

Collection Area No. Accessions Location of Storage

Argentina/Bolivia 112 USDA-PI/ Salta, Argentina

Honduras 111 USDA-PI / Zamorano

Honduras landraces 452 Zamorano

Tanzania landraces 80 USDA-PI

Caribbean 65 Haiti/Puerto Rico/ DR

Domincan Republic 28 USDA-PI / IDIAF (DR)

Total 848

Accessions of Common Bean and Related Species

Accessions of Cowpea Germplasm

Cowpea collections from Africa increased USDA-PI holdings from 2,000 to 7,000 in 20 years

USA elite breeding lines crossed to landraces from Africa and the Americas

•In 1980’s USA beans had narrow germplasm base

•Crosses broaden genetic diversity and

•Increase resistance to biotic stresses.

Use of exotic bean germplasm by Bean/Cowpea CRSP researchers

• A unique source of resistance to Bean Golden Yellow Mosaic derived from P. coccineus (Univ. of Puerto Rico)

• Wild tepary bean germplasm is a source of resistance to bean weevil (Oregon State Univ.)

• High-yielding common bean breeding lines developed from a cross with a wild bean accession (Michigan State Univ.)

• Dominican PC-50 used for white mold and adult plant rust resistance (Univ. of Nebraska)

Biodiversity of Bean Lines in the Caribbean

• Dominican landraces were characterized and used to improve bean production

• Haitian bean germplasm may be a source of unique combinations of Andean and Mesoamerican genes for disease resistance.

Overlooked area of biodiversity-Plant associated microbes

Pathogen Location Number/races/isolates

Uromyces appendiculatus

UN-L, USDA 550

Rhizoctonia solani UN-L, Cornell >200

Colletotrichum lindemuthianum

Zamorano, CIAT, MSU

>100

Phaeoisariopsis griseola

Zamorano, UC-Davis, CIAT

>100

Domestic & international culture collection of bean pathogens- Fungal

Pathogen Location Number/races/strains

Xanthomonas campestris pv. phaseoli

UN-L, UC-Davis, CIAT

>300

Pseudomonas syringae

UN-L, U-Wisconsin 480

Pseudomonas syringae pv. phaseolicola

UN-L, CABI >200

Domestic & international culture collection of bean pathogens- Bacterial

Virus Location Number/strains

Bean Golden Mosaic U-WI,

U-AZ, CIAT, Brazil

>100

Bean Golden Yellow Mosaic

U-WI,

U-AZ, CIAT

>200

Bean Common Mosaic

USDA, CIAT 50

Domestic & international culture collection of bean pathogens- Viruses

Location Number/strains

Rhizobium spp.

Other species

U-MN, USDA, CIAT, Australia

>300

Domestic & international culture collection of bean pathogens- BNF Microbes

In addition to new sources of disease resistance and screening methods-

Bean & Cowpea germplasm and pathogen collections

•Unique coevolution of host/pathogen studies- bean rust, web blight

•Transgenic cowpea/insectstudies- pest population diversity

•Farmer association/NAR collaboration- (Dom. Republic)

•Local committees of agricultural research (Ecuador)

•Farmer-managed field trials (Malawi)

•Participatory breeding (Central America)

Deployment of improved bean lines

•Dambos (wetlands) used for seed production in Malawi with minimal impact on natural diversity

On-going need for clean seed of new lines

Present and Future conservation/diversity problems

•Inadequate microbiology conservation locations, e.g. ATCC

•Homeland security / APHIS requires permit for all pathogens/pests

•Underfunding for germplasm collection andconservation

•Developing country fears of losing natural resources- limited or no collections

•Loss of landraces/ wild germplasm

•Loss of funding for CRSPs and IARCs

Present and Future conservation/diversity problems