Hierarchical Cluster Analysis on Potential Resource of Nitrogen Fixing Bacteria at Wheat Monocrop Production Districts of Bale,Ethiopia

doi:10.7176/jbah/9-19-02

Abstract

Wheat monocrop production system at south eastern highlands of Ethiopia is a threat to productivity and adoption of high value highland pulses such as Faba bean which are the most important pulse crop in Ethiopia. Thirty faba bean nodulating isolates trapped from soil collected from twenty eight locations of Bale zone were characterized for possible diversity.For these purposes numerical taxonomy by multivariate cluster analysis based on physiological characteristics was used and according to which entire test isolates were grouped .Dendrogram constructed from cluster analysis of 56 phenotypic traits, grouped them into three clusters and one un-clustered positions at 53% relative similarity. Cluster III contained 58% of the test isolates that were grouped together with the reference strains Rhizobium leguminosarum (FBEAL-110), suggesting that besides to cmmonly nodulated on the study area were also phenotypically diverse. Furthermore, the result indicates the existence of strains in the collection, which can tolerate environmental stresses, thus can be developed into inoculant for highland pulses’ inoculation and production in Ethiopia and beyond. Keywords : Cluster analysis, Monocropping, Rhizobium leguminosarum DOI : 10.7176/JBAH/9-19-02 Publication date :October 31 st 2019

Highlights

Ethiopia is the second- largest producer of faba beans after China (ECX, 2009;IFPRI, 2010;Tamene Temesgen et al, 2015) there is still untouched potential in the country
Ethiopia’s average bean yield is very low when compared to other developed countries. This poor productivity coupled with small per capita land holding of the majority of farmers is a challenge to increasing production and the marketable surplus of bean(ECX, 2009)but potential producer districts are trapped with monocropping production system that affected pulse production and adoption rate
Numerical Data Analysis Phenotypic similarities among 30 isolates and one reference strain(FBEAL-110) were numerically analyzed based on their phenotypic characteristics, such as pH tolerance, salt tolerance, temperature tolerance, Intrinsic antibiotic resistance, Carbon source and Amino acid utilization, using a similarity coefficient and phenogram was constructed by the hierarchical cluster analysis (HCA) based on agglomerative clustering which is the most common type of hierarchical clustering used to group objects in clusters based on their similarity(Kassambara, 2017) and appropriates R packages(factoextra & dendextend) were used(R Core Team, 2019)

Summary

Introduction

Ethiopia is the second- largest producer of faba beans after China (ECX, 2009;IFPRI, 2010;Tamene Temesgen et al, 2015) there is still untouched potential in the country. Our strains fall into fast growing Rhizobia based on doubling time, yellow color indicating the acid producing ability of the isolates on BTBYEMA.This result is consistent to results of other researchers on fast growing Faba Bean nodulating isolates(Abere Mnalku et al, 2009;Zerihun Belay and Fassil Assefa, 2011;Getahun Negash 2015).

Results

Conclusion