Self-incompatibility in passionfruit: evidence of gametophytic-sporophytic control

• Published in: Theoretical and applied genetics 2003, Vol.106 (2), p.298-302
• Main Authors: DE M. F. SUASSUNA, T, BRUCKNER, C. H, DE CARVALHO, C. R, BOREM, A
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Classical genetics, quantitative genetics, hybrids; Crosses, Genetic; Fundamental and applied biological sciences. Psychology; Genetics of eukaryotes. Biological and molecular evolution; Genotype; Genotype & phenotype; Passiflora - genetics; Phenotype; Plant reproduction; Pollen - genetics; Pteridophyta, spermatophyta; Reproduction - genetics; Reproduction - physiology; Vegetals
• ISSN: 0040-5752; 1432-2242
• DOI: 10.1007/s00122-002-1103-1

Self-incompatibility in passionfruit was studied in families originated from crosses among plants that presented differences in reciprocal crosses. The three families, obtained by crossing S(3) plants, exhibited one incompatible group; no reciprocal differences were observed. The phenotype of the families was the same as the parent plants, S(3). These results suggest the presence of a gene ( G), gametophytic in its action, associated to the sporophytic gene S, modifying the incompatibility reaction in passionfruit. The reciprocal difference exhibited in the crosses among the parents could be explained as a matching between plants homozygous for S, but homozygous and heterozygous for G. Actually this would be a partially compatible cross, not detectable when the evaluation is done based on fruit set data. As the family originated from this kind of cross is homozygous for S and heterozygous for G, no reciprocal differences are expected, and the phenotype should be the same as the parental plants, as observed in the present work.