title: Genetic diversity among late blight resistant and susceptible potato genotypes.
abstract: RAPD polymerase chain reaction analysis was used to study the genetic diversity among a wild potato variety Solanum demissum (very resistant to late blight) and six potato cultivars (Hanna, Lady-Olympia, Lady-Rosetta, Spunta, Diamant and Cara) varied in their resistance to Phytophthora infestans. Cluster analysis of six potato genotypes showed that, all tested genotypes were separated into two clusters (1 and 2). Cluster 1, included only the wild potato variety (S. demissum), whereas cluster 2 divided into two groups (G1 and G2). Late blight high resistant cultivars Hanna and Cara were grouped in G1. Group 2 included the moderate resistant cultivar Spunta and the susceptible cultivars Diamant, Lady-Rosetta and Lady-Olympia. The potato cultivars that showed highest genetic similarity to the wild potato variety were the resistant cultivars Hanna and Cara. Lowest genetic similarity was obtained with the susceptible cultivars Lady-Rosetta, Diamant and Lady-Olympia. RAPD primer K17 yielded a band with molecular weight of 936 bp found in all susceptible potato cultivars (Lady-Rosetta, Lady-Olympia and Diamant). On the other hand, band with molecular weight of 765 bp were detected in the wild potato and the resistant cultivars Hanna and Cara. Results of this study suggested that, the RAPD marker technique could be beneficial for revealing the genetic variability of different genotypes of potato varied in their resistibility to late blight.
authors: Plant Pathology Dept., Faculty of Agriculture, Alexandria University, Egypt.
authors: Eid M
authors: EM
authors: Abou-Taleb
authors: Sayed M
authors: SM
authors: Aboshosha
authors: Ebtsam M
authors: EM
authors: El-Sherif
authors: Mahmoud H
authors: MH
authors: El-Komy
keywords: Genetic diversity; Late blight; Potato; RAPD PCR; Resistant marker
references: Annu Rev Phytopathol. 1996;34:479-501
references: 15012553
references: Nucleic Acids Res. 1990 Nov 25;18(22):6531-5
references: 1979162
references: Plant Cell Rep. 1996 May;15(9):662-7
references: 24178606
references: Appl Environ Microbiol. 1998 Oct;64(10):4007-14
references: 9758833