Partial map of Coffea arabica L. and recovery of the recurrent parent in backcross progenies

A.C.B Oliveira,L Zambolim,E.T Caixeta,E.M Zambolim,R.J.N Rufino,N.S Sakiyama

doi:10.12702/1984-7033.v07n02a12

Abstract

A partial map of Coffea arabica L. was constructed based on a backcross population and RAPD markers. From a total of 178 markers evaluated, only 134 that segregated 1:1 (P>0.05) were used to develop the map. Seventeen markers were not linked, while 117 formed 11 linkage groups, covering a genome distance of 803.2 cM. The maximum distance between adjacent markers was 26.9 cM, and only seven intervals exceeded 20 cM. The markers were further used for assisted selection of the plants closest to the recurrent parent, to accelerate the introgression of rust resistance genes in the coffee breeding program. Three BC1 plants resistant to coffee leaf rust and with high genetic similarity to 'Catuai' were selected and integrated in the following backcross cycles.

Highlights

The species Coffea arabica L. (2n=4X=44), the only tetraploid and self-fertile of the genus Coffea, is characterized by low genetic diversity that has been attributed to its allotetraploid origin, type of reproductive biology and evolutionary process
The Arabic coffee type, cultivated until presented no resistance at all to this disease (Etienne et al 2002). Researchers have concentrated their efforts on populations of natural interspecific hybrids, which seem most suitable to be integrated in backcross programs with Arabic coffee types, due to their similar genetic structure to C. arabica
Of the1200 RAPD primers tested for polymorphic marker identification among the parents and F1, 127 (10.6%) amplified consistent fragments in the Híbrido de Timor and F1, which were absent in Catuaí Amarelo

Summary

Introduction

The species Coffea arabica L. (2n=4X=44), the only tetraploid and self-fertile of the genus Coffea, is characterized by low genetic diversity that has been attributed to its allotetraploid origin, type of reproductive biology and evolutionary process. RAPD markers were used to construct a partial gene linkage map of C. arabica. In the segregating population under study, these markers were used to identify plants with the highest proportion of the recurrent parent.

Results

Conclusion