A male-fertile Lycopersicon esculentum × Solanum lycopersicoides hybrid enables direct backcrossing to tomato at the diploid level
Authors: Chetelat, Roger; Cisneros, Pedro; Stamova, Liliana; Rick, Charles
Source: Euphytica, Volume 95, Number 1, May 1997 , pp. 99-108(10)
Abstract:Solanum lycopersicoides Dun. is a wild nightshade native to Chile and Peru that possesses many traits of potential interest to tomato breeders, including environmental stress tolerance, resistances to disease and insect pests, and certain fruit quality characteristics. Sexual and somatic hybrids with the cultivated tomato (Lycopersicon esculentum Mill.) are readily obtained, yet have a strong tendency towards male-sterility combined with unilateral incompatibility, barriers that have deterred breeding efforts in the past. We report herein the synthesis of a partially male-fertile F1 hybrid by sexual crosses between tomato and a recently collected population of S. lycopersicoides. Over 280 BC1 plants were obtained by directed backcrossing to tomato at the diploid level, of which 58 were sufficiently fertile to permit selfing or additional backcrosses. The transmission of S. lycopersicoides genetic markers into a uniform L. esculentum background was confirmed with 24 isozyme or morphological loci on 11 of the 12 alien chromosomes. Potentially useful tolerance to gray mold (Botrytis cinerea) was demonstrated by inoculation of stem cuttings with mycelial plugs: at 6 days post-inoculation, the intergeneric hybrid showed little evidence of disease progression and the length of stem lesions averaged only one third that of susceptible controls.
Document Type: Research Article
Publication date: May 1, 1997