Impact of pesticides on crop injury, yield, market quality, and chemical composition of peanut (Arachis hypogaea L.)

Authors: KAUFMAN, AMANDA - North Carolina State University; JORDAN, DAVID - North Carolina State University; Dean, Lisa; ALLEN, JONATHAN - North Carolina State University; GOODELL, LAURA - North Carolina State University; HARE, ANDREW - North Carolina State University

Submitted to: Peanut Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/9/2026
Publication Date: 4/9/2026
Citation: Kaufman, A.A., Jordan, D.L., Dean, L.L., Allen, J.C., Goodell, L.S., Hare, A.T. 2026. Impact of pesticides on crop injury, yield, market quality, and chemical composition of peanut (Arachis hypogaea L.). Peanut Science. 53(1), p.12-25. https://doi.org/10.3146/0095-3679-53-PS1660.
DOI: https://doi.org/10.3146/0095-3679-53-PS1660

Interpretive Summary: Farming under organic conditions presents a number of challenges. For peanuts, the restrictions against the use of synthetic pesticides makes it difficult to produce economically beneficial crop yields and required quality as defined by flavor, nutrition and sizes or "grades". This study compared the the outcomes of treatments over the course of 2 crop years on these factors for Virginia market type peanuts in North Carolina. Experimental plots were either left untreated, treated with applications acceptable for organic production, or treated with conventional pesticide and herbicide products. Applications of fungicide did not appreciably affect production, but lack of pesticides to treat insect injury resulted in infections of several plant diseases reducing plot yields and pod growth. The peanuts harvested from the untreated fields had lower nutritional content as well as marketable peanut yields. The main effects were found to be from the loss of plants and lower seed production to diseases caused by insect infestation rather than physical effects of the pesticides themselves.

Technical Abstract: Maintaining pod yield, market grade factors, acceptable flavor, and nutritional composition of peanut (Arachis hypogaea L.) can be a challenge in systems where synthetic pest control is limited, such as in organic farming. Higher incidences and severity of diseases, and greater infestations of arthropods and the consequent decreases in yield are reported with limited or no inputs of synthetic pesticides. However, the impact on flavor profiles and nutritional composition for peanut grown in production systems with limited pesticide inputs which allow for significant injury from pests has not been investigated. Field experiments were conducted in 2017 and 2018 in North Carolina to determine the impact of varying levels of pesticide inputs on pest reaction, pod yield, market grade characteristics, flavor, and nutritional composition of the high-oleic cultivar ‘Sullivan.’ Treatments included no input, a simulated organic system, and a conventional production system. Lower yield was observed in systems whenever seed was not treated with commercially-available fungicides and when insecticides were not applied to control tobacco thrips (Frankliniella fusca Hinds) or southern corn rootworm (Diabrotica undecimpuntata Howardi Barber). Early and late leaf sport disease [caused by Passalora arachidicola (syn. Cercospora arachidicola [Hori]) and Nothopassalora personata (Berk. & M.A. Curtis) U. Braun, C. Nakash., Videira & Crous] were suppressed by a copper-containing fungicide regime compared with commercially available fungicides. Although the response was variable, aromatic and sweet flavor were lower with more intensive pest management where injury from pests was often lower. Differences in oleic acid content were not observed based on pesticide inputs and subsequent injury caused by pests. However, total oil content was higher when the commercially available fungicide regime was used compared with copper-containing fungicide. Alpha tocopherol content was highest in samples without disease and fungicide treatments. Total tocopherol content was highest in systems receiving insecticide treatments. Samples harvested in 2017 were evaluated for flavor using a descriptive sensory panel. Perceived sweet flavor, sweet aromatic and total sugar composition was higher in samples receiving no disease treatment. Roast peanutty flavor was not impacted due to the differences in production systems. This research provides insight into the limitations that may result from production systems where fewer inputs are used including reductions in peanut quality, flavor, and nutritional compositions. Difference in chemical composition and flavor of peanut most likely was associated with impacts of pests on peanut growth and development and possibly pod maturation and not a physiological effect from the actual pesticides that were applied. However, additional research is needed to confirm or refute this assumption.