The genetics of qualitative traits in tef

Genetic study on the inheritance of lemma color, seed color and panicle form was conducted to determine: (1) the gene actions and interactions, (2) the number of genes involved, (3) the presence of absence of maternal effects and linkage and (4) the kind of tetraploidy in tef. four cultivars (Fesho, bursa, Kay Murri and Trotteriana), which have differing and contrasting phenotypic characteristics where selected for the study. Six crosses and their reciprocals were effected among the four cultivars, and data were collected on individually transplanted plants and their reciprocals were effected among the four cultivars, and data were collected on individually transplanted plants and their progenies in the F1, F2 and F3, plus in backcross generations. These data were used to determine the inheritance patterns. Four genes controlled lemma color inheritance. This was demonstrated by F2 segregation ratios of 3:1, 12:3:1, 15:1,45:3:16, and 180:12:48:16. Dominance, complementary and epistatic gene actions and interactions were found. Duplicate, pairs of genes were identified for seed color inheritnce. Gene action between the genes and their alleles was simple dominance with additive effects. Fesho (dark-brown seed) produced an F2 ratio of 15 brown: 1 white when crossed with Kay Murri (yellowish-white seed), whereas the result was 3 brown: 1 white for crosses with Trotteriana (medium-brown seed). Panicle form is controlled by duplicate pairs of genes for the degree of losseness and another pair of gnes for branching pattern. Segregation ratios of 15 loose: 1 compact in the loose x compact crosses showed duplicate dominance for gene action. Loose x loose crosses were all loose and compact x compact crosses were also all compact. On the other hand, an F2 segregation ratio of 13 multilateral: 3 unilateral for branching pattern suggested a recessive suppressor type of gene action. No maternal effects of linkages were detected. All the results showed a disomic inheritance pattern for all the three traits studied, which indicates that tef is an allotetraploid. This in turn indicates that quantitative genetic theories developed for diploids can be applied to tef breeding and improvement.