Peanut yield and grade response to multiple simulated rainfall events following inverting

Authors: Bucior, Erika; Sorensen, Ronald; Lamb, Marshall; BUTTS, CHRIS - Retired ARS Employee; Abbas, Hamed

Submitted to: Journal of Sustainable Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/7/2025
Publication Date: 1/16/2025
Citation: Bucior, E.R., Sorensen, R.B., Lamb, M.C., Butts, C.L., Abbas, H.K. 2025. Peanut yield and grade response to multiple simulated rainfall events following inverting. Journal of Sustainable Agriculture. 4:e70043. https://doi.org/10.1002/sae2.70043.
DOI: https://doi.org/10.1002/sae2.70043

Interpretive Summary: During peanut (Arachis hypogaea L.) harvest, weather conditions may suddenly change from a drought to a high rainfall scenario. During this time of intense rainfall situations, pods are left in windrows to dry down for days and possibly weeks before pod harvest. In recent years there has been increasing frequency and intensity of rainfall events that have occurred during the harvest of peanut, especially with fluctuating hurricane seasons. Peanut pods are exposed to these variable weather elements longer than normal. Growers and storage managers commonly agree that exposure to inclement weather patterns in the windrow reduces peanut yield and quality. In this three-year study, peanuts were dug at optimum maturity, left in the windrow, and exposed to variable depths of simulated rainfall (over 150 mm simulated and natural rainfall). Peanut yield, quality characteristics, and aflatoxin contamination were measured. Across all three years, as cumulative simulated rainfall increased, pod yield decreased, while loose shelled kernels and splits increased. In 2022 and 2023, the length of time peanuts were left in the field increased, total simulated rainfall also increased, resulted in greater strength of significance difference increased within the measured variables. There was no increase of aflatoxin with time or rainfall compared with optimum maturity, probably due to cooler temperatures and high soil moisture. This suggests that short precipitation events may only slightly impact yield and quality metrics, whereas increased time and precipitation, may impact grower yield and peanut quality more significantly.

Technical Abstract: During peanut harvest, the weather can quickly shift from drought to heavy rain. When it rains a lot, peanut pods are left in rows to dry for several days or even weeks before they are collected. Recently, intense and frequent rainstorms, often linked to hurricane seasons, have become more common during peanut harvest. This means the peanuts are exposed to bad weather for longer than usual. Farmers and storage managers agree that this negatively affects both the quantity and quality of the peanut harvest. In this three-year study, peanuts were harvested at the right maturity, left in the field in rows, and subjected to different amounts of simulated rain (over 150 mm). The researchers measured peanut yield, quality, and aflatoxin contamination. Over the three years, as rainfall increased, the peanut yield decreased, and the number of damaged peanuts (like split or loose shelled kernels) increased. In 2022 and 2023, longer exposure to rain resulted in stronger differences in these variables. However, there was no increase in aflatoxin levels, likely because cooler temperatures and wet soil prevented its growth. The study suggests that short rain events have a small effect on yield and quality, but longer rain exposure significantly reduces both.