Resistance to bacterial wilt in somatic hybrids between Solanum tuberosum and Solanum phureja

• Published in: Plant science (Limerick) Vol. 160; no. 1; pp. 165 - 176
• Main Authors: FOCK, I, COLLONNIER, C, SIHACHAKR, D, PURWITO, A, LUISETTI, J, SOUVANNAVONG, V, VEDEL, F, SERVAES, A, AMBROISE, A, KODJA, H, DUCREUX, G
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Science 07.12.2000; Elsevier
• Subjects: Agronomy. Soil science and plant productions; Biochemistry, Molecular Biology; Biological and medical sciences; Biotechnology; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; Haploidy, in vitro culture applications, somatic hybrids; Life Sciences; Plant breeding: fundamental aspects and methodology; Ralstonia solanacearum; Solanum solanacearum; Solanum tuberosum; Vegetal Biology; Ploidy; Plant pathogen; Ralstonia solanacearum; Isozyme; Solanum tuberosum; Cell fusion; Random amplified polymorphic DNA marker; Disease resistance; Sensitivity resistance; Dicotyledones; Morphology; Protoplast; Angiospermae; Interspecific hybridization; Bacteria; Wild plant; Somatic hybrid; Spermatophyta; Tuber plant; Solanaceae
• ISSN: 0168-9452; 1873-2259
• DOI: 10.1016/s0168-9452(00)00375-7

Somatic hybrid plants were produced after protoplast electrofusion between a dihaploid potato, cv. BF15, and a wild tuber-bearing relative, Solanum phureja, with a view to transferring bacterial wilt resistance into potato lines. A total of ten putative hybrids were selected. DNA analysis using flow cytometry revealed that six were tetraploids, two mixoploids, one amphiploid and one octoploid. In the greenhouse, the putative hybrids exhibited strong vigor and were morphologically intermediate, including leaf form, flowers and tuber characteristics. The hybrid nature of the ten selected plants was confirmed by examining isoenzyme patterns for esterases and peroxidases, and analysis of RAPD and SSR markers. Analysis of chloroplast genome revealed that eight hybrids possessed chloroplast (ct) DNA of the wild species, S. phureja, and only two contained Solanum tuberosum ct type. Six hybrid clones, including five tetraploids and one amphiploid, were evaluated for resistance to bacterial wilt by using race 1 and race 3 strains of Ralstonia solanacearum, originating from Reunion Island. Inoculations were performed by an in vitro root dipping method. The cultivated potato was susceptible to both bacterial strains tested. All somatic hybrids except two were tolerant to race 1 strain, and susceptible to race 3 strain. Interestingly, the amphiploid hybrid clone showed a good tolerance to both strains.