Stability of resistance to Phytophthora infestans in potato: an international evaluation

Authors: Forbes, G. A.¹; Chacón, M. G.²; Kirk, H. G.³; Huarte, M. A.⁴; Van Damme, M.⁴; Distel, S.⁴; Mackay, G. R.⁵; Stewart, H. E.⁵; Lowe, R.⁵; Duncan, J. M.⁵; Mayton, H. S.⁶; Fry, W. E.⁶; Andrivon, D.⁷; Ellissèche, D.⁸; Pellé, R.⁸; Platt, H. W.⁹; MacKenzie, G.⁹; Tarn, T. R.¹⁰; Colon, L. T.¹¹; Budding, D. J.¹¹; Lozoya-Saldaña, H.¹²; Hernandez-Vilchis, A.¹²; Capezio, S.¹³

Source: Plant Pathology, Volume 54, Number 3, June 2005 , pp. 364-372(9)

Publisher: Blackwell Publishing

Key:

- Free Content

- New Content

- Subscribed Content

- Free Trial Content

Abstract:

Ten institutions in nine countries joined together to test the stability of resistance of 14 potato genotypes to the oomycete pathogen Phytophthora infestans in three separate trials. Seven of the genotypes were tested in one trial involving seven locations, and all 14 were tested in two subsequent trials, each involving eight locations. Stability of resistance was tested with nonparametric tests and with an additive main effects and multiplicative interaction (AMMI) model. Overall, resistance to P. infestans was robust; resistant genotypes were consistently resistant in all locations and trials. The nonparametric analysis indicated that specific genotypes were basically stable across sites for resistance. In trial 3, the Z statistic for overall stability was significant at 0·05%, indicating a significant level of interaction across the trial, but there were no significant interactions for specific genotypes in this trial. The genotype by environment (G × E) effect of the AMMI model was highly significant in both trials, but the mean square of G × E was less than 10% of the genotype effect in each trial. The first two principal components (PCA1 and PCA2) of the AMMI analyses together explained 75 and 80% of the interaction effects in trials 2 and 3, respectively. Based on both nonparametric and AMMI analyses, Ecuador and Argentina were locations of relatively high interaction effects for both trials 2 and 3, although in Ecuador this interaction was not associated with any particular potato genotype. Other locations also had high interaction effects, but these occurred in only one trial. The genotypes Chata Blanca and, to a lesser extent, Torridon were relatively unstable in trials 2 and 3, but in the case of Torridon, resistant, this did not represent a significant loss of resistance.

Keywords: area under disease progress curve; field disease assessment; genotype × environment; principal component analysis; potato late blight; quantitative resistance; race-nonspecific resistance

Document Type: Research article

DOI: 10.1111/j.1365-3059.2005.01187.x

Affiliations: 1: International Potato Center (CIP), Apartado 1558, Lima 12, Peru; 2: CIP, PO 17-21-1977, Quito, Ecuador; 3: LKF, Grindstedvej 55, Vandel, Denmark; 4: INTA, Est. Exp. Balcarce C. C. 276, Argentina; 5: SCRI, Dundee DD2 5DA, UK; 6: Cornell University, Ithaca, NY, USA; 7: UMR INRA-Rennes Agrocampus BiO3P, BP 35327, F-35653 Le Rheu Cedex, France; 8: UMR INRA-Agrocampus Rennes APBV, Keraiber, F-29260 Ploudaniel, France; 9: AAFC, PO Box 1210, PEI, Canada; 10: AAFC, PO Box 20280, Fredericton, NB E3B 4Z7 Canada; 11: PRI, Wageningen, the Netherlands; 12: PICTIPAPA, Toluca, México; and 13: Facultad de Ciencias Agrarias Balcarce, UNMdP, cc 276 (7620) Balcarce, Argentina

You have access to the full text article on a website external to Ingentaconnect.

Please click here to view this article on Synergy.

You may be required to register and activate access on Synergy before you can obtain the full text. If you have any queries please contact onlinehelp@oxon.blackwellpublishing.com

Key:

- Free Content

- New Content

- Subscribed Content

- Free Trial Content