Intraspecific somatic and sexual hybridisation between dihaploid lines of Solanum tuberosum L.: evaluation of morphological traits and resistance to late blight Phytophthora infestans (Mont.) de Bary in the foliage

• Published in: Euphytica 1996, Vol.90 (2), p.209-216
• Main Authors: Cooper-Bland, S. (Scottish Crop Research Inst., Invergowrie, Dundee (United Kingdom)), Maine, M.J. De, Stewart, H.E, Fleming, M.L.M.H, Phillips, M.S, Kumar, A
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Biotechnology; Breeding schemes. Varia; DIHAPLOIDIA; DIHAPLOIDIE; DIHAPLOIDY; DISEASE RESISTANCE; Fundamental and applied biological sciences. Psychology; FUSION DE PROTOPLASTES; FUSION DEL PROTOPLASTO; Genetics and breeding of economic plants; Haploidy, in vitro culture applications, somatic hybrids; HIBRIDACION; HIBRIDACION SOMATICA; HYBRIDATION; HYBRIDATION SOMATIQUE; HYBRIDIZATION; PHYTOPHTHORA INFESTANS; Plant breeding: fundamental aspects and methodology; PROTOPLAST FUSION; RESISTANCE AUX MALADIES; RESISTENCIA A LA ENFERMEDAD; SOLANUM TUBEROSUM; SOMATIC HYBRIDIZATION
• ISSN: 0014-2336; 1573-5060
• DOI: 10.1007/BF00023860

Intraspecific tetraploid somatic and sexual hybrid plants have been resynthesised following protoplast fusion and by sexual crosses between two dihaploid potato (Solanum tuberosum) lines each possessing complementary agronomic traits. The dihaploid PDH 40 possesses good tuber shape and yield but has foliage susceptibility to late blight (Phytophthora infestans). On the other hand, the dihaploid PDH 727 possesses resistance to blight in the foliage but has a low yield of small and irregular shaped tubers. Since it was only possible to use a partial selection strategy based on culture media to facilitate recovery of somatic hybrid plants - further morphological and esterase isozyme based characterisations were performed to identify somatic hybrid plants from amongst the non-hybrid plant material. When the blight resistance of both the intraspecific somatic and sexual hybrid plants was assessed there was no significant difference in the mean resistance value and it was intermediate between those of their parents. However, the range of resistance was much wider among the sexual hybrids than among the plants derived from somatic fusion. An assessment of tuber yield between tetraploid sexual and somatic hybrids showed no significant difference and it was higher than that of either parent value. The implication of these results in the context of potato genetics and breeding is discussed.