Impacts of Anthropogenic, Environmental, and Genetic Factors on Peanut Seed Protein Content and Composition

Abstract

Peanut contributes approximately $4 billion annually to the U.S. economy, with 13 peanut producing states generating over 3 mmt, 75 to 80% of which is consumed domestically. Peanut seeds contain 22 to 36% protein and 40 to 56% oil, enriched in unsaturated fatty acids, making them a highly nutritious food source. However, specific seed storage proteins can trigger allergic reactions ranging from mild symptoms to severe anaphylaxis, underscoring the need to better understand factors influencing seed protein composition. Anthropogenic processes such as domestication and modern breeding, environmental stresses including excessive heat during flowering and pod development, and genetic mechanisms such as homoeologous exchanges (HEs) collectively shape seed protein content and composition. Domestication improved harvestability, while breeding enhanced yield and nutritional quality. Current improvement programs increasingly emphasize heat resilience in response to a ~1.5 C rise in global temperatures, with further warming anticipated. Yet limited attention has been given to how these factors affect protein composition, allergenic potential, trait stability under future climates, and genotypic uniformity linked to HEs. Here, we review the impacts of domestication, breeding, environmental stress, and genomic restructuring on peanut seed protein content and composition, highlighting key research gaps to ensure nutritional quality, safety, and stability in a changing climate.