Genetic Variation, Genotype by Environment Interactions and Grain Yield Stability Analysis in Finger Millet Accessions Resulted in the Release of an Improved Variety

Abstract

The use of multiple data sets, such as morphological, biochemical and molecular in combination with appropriate statistical analysis tools are essential in  identifying inter and intra-species variation to develop improved cultivars. To this end, a total of 150 finger millet accessions, of which 105 were collected  from Ethiopia, 39 introduced from eastern and south eastern Africa and six commercially released Ethiopian varieties were evaluated at Arsi Negele and  Gute research sites in 2011. Among those, 138 accessions were genotyped using 20 Simple Sequence Repeat (SSR) markers at International Crop  Research Institute for Semi-Arid Tropics (ICRISAT), Nairobi, in 2012. Highly significant (P ≤ 0.01) variations were observed among the 150 accessions for  grain yield and other agronomic traits. A total of 199 alleles were recorded with an average of 9.95 alleles per microsatellite locus and polymorphism  information content (PIC) of 0.57 was observed. Hierarchical clustering based on major phenotypic traits revealed that the majority of accessions from  the same region and adjoining geographical region shared strong phenotypic similarity and thus grouped together. Weighted Neighbor Joining based on  SSR data grouped the test accessions into three major clusters that were not entirely based on geographical origin. Based on the magnitude of  phenotypic and genotypic diversity and blast disease tolerance, 30 finger millet genotypes were selected for further evaluation at multi-location (Arsi  Negele, Assosa, Bako and Gute) in the 2012 and 2013. Additive Main effect and Multiplicative Interaction (AMMI), and Genotype and Genotype by  Environment Interaction (GGI) biplot analysis revealed that Acc. 203544 was found to be the most stable and highest yielding (3.16 ton ha^-1), with yield  advantage of 13.7% over the best standard check, Gute (2.78 ton ha^-1). Thus, this accession was officially released with the name “Addis-01” and  recommended for production in the test environments and similar agro-ecologies in the country.