DOI: 10.36347/sajb.2015.v03i09.004

Pages: 746-751

Commercial coffee production relies on two species, Coffea arabica and Coffeea canephora. Popularly known as arabica and robusta coffees respectively, the two species differ in their ploidy level (tetraploid and diploid), breeding behaviour (self and cross compatible), adaptability (high and low elevations) and agronomic performance. Transfer of desirable genes, in particular for disease resistance from diploid robusta into tetraploid arabica cultivars without affecting quality has been the main objective of arabica breeding. Occurrence of spontaneous tetraploid interspecific hybrids between robusta and arabica facilitated for arabica coffee improvement through introgressive breeding in India and elsewhere in the world. Catimor and Sarchimor were two popular semi-dwarf varieties of arabica developed by introgressive breeding. A new semi-dwarf line, S.4634 was developed from reciprocal crosses of Catimor and Sarchimor with an objective of developing a vigorous semi-dwarf coupled with durable resistance. The hybrid populations were subjected to selection and progenies were established for on-farm evaluation of agronomic performance. The present study involved molecular profiling of selected plants from these hybrid progenies along with the parental lines using SRAP marker approach. The SRAP assays proved efficient as 18 variety/genotype specific fragments were identified, 15 fragments in Sarchimor and three fragments in Catimor. Analysis of introgression revealed that the extent of Sarchimor introgression varied from 13.33% to 86.67% in hybrid plants analysed, which was also reflected in variable agronomic performance of these progenies especially with respect to field tolerance to leaf rust and bean size. The results clearly established the genomic status of the S.4634 derivatives in comparison with Sarchimor and Catimor lines.