Genetic Variability and Association Among Agronomic Characters in Selected Field Pea ( Pisumsativum L. ) Genotypes at Bale Zone, Sinana Research Center, Oromia Region, Ethiopia

Abstract

Field pea ( Pisumsativum L. ) is an annual herbaceous legume belonging to the family Fabaceae that adapted to cool moist climate with moderate temperature. The species P. sativumis dominant in Ethiopia even though wild and primitive forms are also known to exist in the high elevation of the country. No sufficient work has been done for understanding and describing the nature and extent of genetic variability on Field Pea. Thus use of genetic variability is suggested to alleviate the shortage of released varieties in Field pea. The studies of association characters solve the low yield of field pea in Ethiopia. Therefore, the present study was conducted to study genetic variability and association among agronomic characters of field pea ( Pisumsativum L. ) genotypes. The field experiment was conducted using 29 varieties and 7 accessions at Sinana Agricultural Research Centre during 2013/14 main growing season. Treatments were arranged in Simple Lattice design with two replications. The results obtained revealed that the mean squares of the genotypes were highly significant for most of the characters (p < 0.05) except for days to emergence, days to flowering, pods per plant, above ground biomass and harvest index implying that wide range of variability has been obtained for the traits studied. The genotypic coefficient of variation ranged from 2.91% for plant height to 37.9% for above ground biomass, while phenotypic coefficient of variation ranged from 6.28% for days to maturity to 62.6% for above ground biomass. The estimated broad sense heritability ranged from 6.9% for yield per plant to 93.0.0% for pod length. Correlation between different traits and seed yield indicated that there was marked positive and highly significant association of seed yield with days to emergence (rg=0.296**), days to maturity (rg=0.184**), seeds per pod (rg=0.325**) and harvest index (rg=0.341**) indicating the yield improvement perhaps be contributed to changes in these traits. The path analysis at phenotypic level revealed that maximum positive direct effect was exerted by 100 seed weight (1.754) followed by pod length (2.211) and days to emergence (2.056). These traits best contributing to yield variation that emphasis by breeders for future yield improvement of the crop. It can be conclude that Field pea yield can be successfully improved by studying genetic variability and its agronomic characters.