Submitted to: Peanut Science
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/22/2008
Publication Date: 1/31/2008
Citation: Isleib, T.G., Tillman, B.L., Pattee, H.E., Sanders, T.H., Hendrix, K., Dean, L.L. 2008. Genotype-by-environment interactions for seed composition traits of breeding lines in the uniform peanut performance tests. Peanut Science Vol. 35(2): 130-138. Interpretive Summary: The chemical make up of peanuts is caused by both genetic influences and growing conditions and how they interact. The paper examined these influences on peanuts using data gathered from a testing program known as the Uniform Peanut Performance Tests (UPPT). This bank of data allowed for evaluation of effects that can be associated with year of growth, place of growth, breeding line and peanut size and their interactions. A statistical method known as the restricted maximum likelihood estimation of variance components test was used. The main differences seen were oil makeup was affected by breeding line and tocopherol (Vitamin E) composition was affected by both breeding line and growth location. Sugars were affected much more by growing location than by breeding line. These changes are indications that breeding of specific crosses can affect these components for the better.
Technical Abstract: Peanut composition is influenced by several groups of factors: environmental, genetic, and interactions between them. This study evaluated the relative contributions of these factors using data from the USDA-ARS program of quality testing of samples from the multi-state Uniform Peanut Performance Tests (UPPT). Data were subjected to restricted maximum likelihood estimation of variance components reflecting the main effects of year, production region, location within regions, genotype, and kernel grade (“size”) within genotype, and the interactions among these main effects. Oil content exhibited little genetic variation (9% of total variation), however fatty acid composition of the oil was highly influenced by genotype (34-77%) with the exception of lignoceric acid (1%). Tocopherols generally showed less genetic influence than fatty acids. Environmental variation of tocopherols was greater than the variation attributable to GxE. The lowest genetic variation was observed in sugar content, however environmental variation was high (68%). The magnitude of genetic influence on oil content and fatty acid concentrations suggests that these traits are amenable to improvement through breeding.