Association of Agro-Morphological and Oil Traits in Groundnut (Arachis hypogaea L.) Cultivars

Abstract

The associations between the traits of interest in plant breeding are commonly evaluated by means of phenotypic, genotypic and environmental correlations, and through path coefficient analysis that shows direct and indirect cause and effect relationship. Sixteen groundnut genotypes (including local check) were evaluated for quantitative parameters. The crop was sown during 2015 wet season across four locations in Ethiopia. The experiment was laid out in Randomized Complete Block Design (RCBD) with two replications. The results indicated that genotypic correlations were higher than the phenotypic and environmental ones. The grain yield (kg/ha) has presented positive and significant genetic correlation with PWP, SWP and 100SW. Genetic correlations of oil content with agro-morphological traits and oil quality parameters were shown that oil content was significant and positively correlated with pod weight per plant (PWP) and seed weight per plant (SWP) showing that possibility of indirect selection for oil content through these traits. The path analysis based on genotypic correlation in the present study was shown that selection for oil content trait is effective through OY, GY, NMP and NSPOD; breeding for TPUS/TS trait is effective through selection for high oil content, NMP, PWP, AGBP, O/L ratio, and NSP traits. Furthermore, the path analysis has shown that breeding for high O/L ratio can be conducted through selection for AGBP, NSPOD, NSP, oil content, TPUS/TS or oleic acid traits; likewise breeding for oil yield (OY) can be conducted via selection for oil content, NSP, AGBP, NBP or TPUS/TS.