ECOPAPA is the Enrichment of Potato Breeding Programs in Latin America and Europe with Resistance to Late Blight, Phytophthora infestans (ERBIC18 CT98 0318) Project, whose partners are located in Argentina (INTA, Instituto Nacional de Technología Agropecuaria); Bolivia (Fundación PROINPA, Foundation for the Promotion and Research of Andean Products); France (INRA, Institut National de la Recherche Agronomique); United Kingdom (SCRI, Scottish Crop Research Institute); Uruguay (INIA, Instituto Nacional de Investigación Agropecuaria); and the Netherlands (PRI, Plant Research International), which also has a coordinating role. ECOPAPA is financed by the European Union.

The goal of this project is to provide new germplasm to broaden the genetic base of late blight resistance in the breeding programs in the participating countries and to stimulate the development of new resistant cultivars. The transfer of knowledge and technology for marker-assisted breeding for the resistance in this germplasm to scientists in Latin America and Europe is a second goal. ECOPAPA held its first meeting at the GILB’99 Conference, 16–19 March 1999 in Ecuador [See GILB Newsletter No. 7, April 1999]. A short report on the ECOPAPA project appeared in the GILB Newsletter No. 11, August 2000. A second ECOPAPA meeting was held 10–11-September 2001 in Uruguay and a third 20 July 2002 in Germany, following the GILB’02 and the EAPR 2002 conferences. This is a short update of the progress of the project.

The 36 parental genotypes (six from each institution, including both 2x and 4x) were multiplied and distributed by SCRI and the first cycle of the multi-site testing of foliage resistance to late blight took place. The second cycle is in progress. Preliminary analysis by PRI of the results of the foliage testing by four of the partners indicates a good correlation between AUDPC and the apparent infection rate, in most cases. The analysis for the three European partners correlate rather closely with one other and less with the Argentinean results. The Bolivian results present a completely different pattern. INIA is testing the 36 genotypes for tuber resistance to late blight in Uruguay.

Analysis of the P. infestans populations infecting these genotypes in the multi-site foliage testing has been accomplished for four of the partners. The major conclusions of a similarity analysis by SCRI, based on AFLP data, are that the Bolivian isolates form a homogeneous group, all being of the A2 mating type and metalaxyl resistant, and they have little similarity to the isolates from other sites. The French and UK isolates are of the A1 mating type and metalaxyl resistant with certain clustering between them, depending on the primer combinations. The Dutch isolates are quite distinct from the other European (French and UK) isolates and show the greatest genotypic and phenotypic variation including both the A1 and A2 mating types and metalaxyl-resistance or metalaxyl-susceptibility. Virulence studies carried out by INRA indicate that virulence factors 1, 3, 4, 7 are common and factors 2, 6 and 8 are rare. Factor 5 was not detected. Testing for factor 9 will take place presently. PRI will carry out aggressiveness testing on a group of isolates chosen to represent a large genetic variation.

INRA has determined oospore production. Oospores were easily obtained on media in all combinations tested. In leaflets there were clear differences between combinations in the amount of oospores produced. The aim of the analysis is to have an impression on the potential oospore production in South America. Currently the A1 and A2 mating types are spatially separated, but this situation may change. On the other hand, in 1992 both mating types were present in Argentina, while in 1997 only the A2 type remained.

The INTA Solanum chacoense diploid mapping population has been tested for foliar resistance four times and work on a linkage map is underway. QTLs (quantitative trait loci) were identified for three field tests. The SCRI S. phureja backcross diploid mapping population has been tested for foliar resistance and a test for tuber resistance is in progress. DNA has been isolated from this population and genotyping using both SSR and AFLP markers will soon be completed. PRI scientists are working on a different marker approach using Resistance Gene. Analogues (RGA’s). Scientists from INTA, INIA and PROINPA have received training in molecular marker techniques.

It is expected that the project will finish this year and the final results will be presented in scientific journal articles. Submitted by Roeland Voorrips, Coordinator ECOPAPA, email:  R.E.Voorrips(at)plant.wag-ur.nl