Review on Heterosis and Combining Ability Study for Yield and Morphological Characters of Coffee (Coffea arabica L) in Ethiopia

Dula Geneti

doi:10.7176/jees/9-12-03

Abstract

Ethiopia is both the center of origin and diversification of Coffee arabica. Despite the existence of high genetic diversity in coffee population that provides immense opportunities for improvement program, shortage of improved varieties (pure line and hybrid varieties) is the major one. It is obvious that research work carried out so far on coffee genetics and breeding was not adequate to address these diverse agro-ecologies of the country. Heterosis and combining ability studies are some of the basic breeding tools to address such problems. Some studies had been focused on assessment of heterosis and combining ability analysis for yield and morphological characters of coffee in Ethiopia and the presence of heterosis was reported in crosses of selected indigenous C. arabica L. varieties in Ethiopia under different set of studies mainly due to presence of diverse parental lines. These results clearly suggested that the possibility to bring significant coffee improvement through heterosis and combining ability analysis. Therefore, continuous crossing program should be required to acquire many more cross combinations for intensive and extensive evaluation to develop better performing and high yielding hybrids for Ethiopian origin coffee. Keywords: Coffee Arabica, morphological traits, yield, Heterosis and combining ability DOI : 10.7176/JEES/9-12-03 Publication date: December 31 st 2019

Highlights

Coffee (Coffea arabica L.) belongs to the family Rubiaceae and the genus Coffea (Coste, 1992)
In any crop breeding program intended to address such problems like the ones mentioned above, heterosis and combining ability studies are some of the basic breeding tools
The observed level of positive heterosis over the mid and better parent for characters of plant height, canopy diameter, average length of primary branch and number of primary branches may suggest that dominant and partially dominant genes were important in controlling the expression of those characters and that hybridization could be the best approach to improve the performance of these characters

Summary

Introduction

Coffee (Coffea arabica L.) belongs to the family Rubiaceae and the genus Coffea (Coste, 1992). The crop spreads widely in the country stretching from the river bank of Gambella plain (550m.a.s.l) to the central and Eastern highlands of the country with an altitude as high as 2600m (Bayetta, 1986) Within this range of altitudes and ecological diversity, there exists considerable genetic diversity within the cultivated and traditionally recognized land races of arabica coffee in Ethiopia (Dessalegn, 2002). In any crop breeding program intended to address such problems like the ones mentioned above, heterosis and combining ability studies are some of the basic breeding tools. The analysis of combining ability is the other important tool which has presently become an integral part of a breeding program It helps to identify the best combining parent, to know the type of. The present review on coffee heterosis and combining ability study was initiated to conduct systematic investigations by concentrating on crosses between variable parental lines originated from specific country, in this case region of Ethiopia, and contribute to identify the current problem of coffee heterosis and combining ability that leads to solve coffee heterosis and combining ability problems towards improving productivity and quality in the long term

Findings

Discussion

Conclusion