Symbiotic Effectiveness of Elite Rhizobia Strains Nodulating Desi Type Chickpea (Cicer arietinum L.) Varieties

Chickpea (Cicer arietinum L.), is a multi-functional crop with important role in the diet as affordable protein source and in sustaining soil fertility through nitrogen fixation. However, its productivity in Ethiopia of 1.9 t ha-1 is lower than its potential of 5 t ha-1 under well managed conditions, partly due to soil fertility limitations. Field experiments were conducted to evaluate effectiveness of elite rhizobia strains on productivity of chickpea. Four rhizobial inoculant treatments and one control with three chickpea varieties were used. Inoculated plants had significantly (p<0.05) better performance with most of the symbiotic traits, grain yield and yield related traits than non-inoculated treatments. Shoot nitrogen yield was increased in the range of 13.0 – 31.34% by inoculation with strain ICRE-025 over the two test sites. The highest level of N fixation was achieved in genotype ICC-4918 by inoculation with EAL-029 and ICRE-025. Investigations at both test sites demonstrated that inoculation of chickpea varieties with native rhizobial strains were effective and useful for optimized chickpea production

Genotype by environment interaction on yield stability of desi type chickpea (Cicer arietinum L.) at major chickpea producing areas of Ethiopia

This study was conducted to determine the interaction between chickpea genotypes with the environment (GxE) on the yield stability and adaptability of desi type chickpea genotypes (Cicer arietinum L.). Seventeen chickpea genotypes were evaluated for two cropping years (2012/2013 – 2013/2014) at four locations i.e., eight environments (locations x years combination). Chickpea grain yield was significantly (p<0.01) affected by genotypes, the environments and GxE interaction, indicating that the varieties and the test environments were diverse. GxE was further partitioned by principal component axes. The first two principal components cumulatively explained 53.1% of the total variation, of which 32.7% and 20.4% were contributed by IPCA1 and IPCA2, respectively. This implies that the interaction of 17 chickpea genotypes with eight environments was predicted by the first two principal components. AMMI1 biplot analysis showed five adaptive categories of genotypes based on similarities in their performance across environments. The AMMI2 biplot generated using genotypes and environmental scores for the first two IPCAs revealed positioning of the five genotype groups (GC) into four sectors of the biplot. Among them, two genotypes in GC 5 (G5 and G11) exhibited high yields across environments, low IPCA1 scores, low AMMI stability value (ASV) and yield stability index (YSI). G5 was released as a new variety, ‘Dimtu’ and registered in the Official Varieties Catalogue of Ethiopia, 2016