English

Beksisa Lemi,Ayano Ashenafi,Alamerew Sentayew,Daba Gerba

doi:10.5897/ajar2017.12788

Abstract

Lack of suitable varieties that exhibit stable yield performances across wide ranges of environments is the major factor among several production constraints contributing to low productivity of Arabica coffee in Ethiopia. Eleven advanced Limmu coffee genotypes were evaluated in eight environments (four locations over two years) to determine the existence of GEI and yield stability performances. The experiment was laid out in a randomized complete block design of two replications under all locations. Combined analysis of variance showed a highly significant effect of genotype by environment interaction indicating the differential yield response of genotypes across different environments. The major proportion of the variation explained by environments was 42.74% of the total variation. Nevertheless, the contribution of the genotypes to the total variance was much smaller than the environments, and the genotype by environment interaction. Different stability models such as additive main effect and multiplicative interaction (AMMI), AMMI stability value, cultivar superiority index and yield stability index were used for stability analysis. The first two Interaction Principal Component Axis (IPCAs) of AMMI exhibited a highly significant effect and cumulatively contributed about 63.21% of the total interaction sum of squares. Two high yielding genotypes, namely (L52/2001) and (L55/2001), on average, showed stable performance across environments. On the other hand, the study also illustrated the presence of location specific high yielding coffee genotype such as L56/2001. Regarding the test environments, Gera 2015/16 (E5) is considered as a more stable site over the rest environments, while Agaro 2015/16 (E7) was considered to be the most interactive environment. Based on the result of the study, coffee breeders or farmers would be recommended for wise selecting either for location specific or wider adaptable coffee genotypes leading to substantial yield increase under Limmu coffee growing areas.   Key words: Arabica coffee, environment, G x E interaction, stability.

Highlights

IntroductionArabica coffee is the most widely consumed and highly preferred international beverage mainly for its best quality and is one of the most important agricultural commodities in the world contributing to more than 60%
Such presence of a significant G x E interaction complicates breeding strategy because superiority of genotypes across environments cannot be identified by considering their mean performance and the need to develop genotypes that are adapted to specific environmental conditions or the need to identify genotypes that are exceptional in their stability performances across environments
In Ethiopia where coffee production plays a major role in the national economy, yield fluctuation and yielding pattern of coffee being varied with small geographic variation and attributed to low productivity

Summary

Introduction

Arabica coffee is the most widely consumed and highly preferred international beverage mainly for its best quality and is one of the most important agricultural commodities in the world contributing to more than 60%. In Ethiopia, coffee cultivation plays a fundamental role both in the cultural and socioeconomic life of Ethiopians. It represents the major agricultural export crop, providing 20 to 25% of the foreign exchange earnings (ECFF, 2015). Lack of high yielding improved varieties for each agro ecological zones and lack of suitable varieties that exhibit stable performance across wide ranges of environments are the major constraints in coffee production and productivity in Ethiopia (Bayetta, 2001; Yonas and Bayetta, 2008)

Methods

Results

Conclusion