Variability and trait association in culm and grain yield characteristics of recombinant inbred lines of Eragrostis tef Eragrostis pilosa

A study was conducted to assess variability and association in some culm and grain yield characteristics of recombinant inbred lines of a cross between Eragrostis tef and Eragrostis pilosa. A total of 81 lines were evaluated using randomized complete block design at Akaki and Debre Zeit, Ethiopia in 2007. Analysis of variance indicated that there exists difference among the recombinant inbred lines of similar and different parental genotypes. Grain yield revealed high (>30%) genetic coefficient of variation while lodging index revealed moderate (>15%). Moderate (>10%) genetic coefficient of variation was also recorded for plant height, panicle length and culm characters. Genetic advance was high for grain yield (>50%) and lodging index (>20%). Moderate (>10%) genetic advance was recorded for culm related characters. Most associations of the characters considered in the study were positive. Lodging index revealed consistently strong association with second culm strength that would be a point of further investigation. The variability among the recombinant inbred lines considered in this study has verified importance of E. pilosa in diversifying germplasm base for tef crop improvement. Existence of considerably high genotypic variability between recombinant inbred lines of different parental genotypes has also put a promise to further tef crop improvement, through crossing with many more genotypes of E. pilosa. Difference revealed between the sites implicating the need to work on more environments to represent major tef growing conditions.