Competing with the competitors in an endless competition: a systematic review of nonchemical weed management research in peanut (Arachis hypogea) in the United States

Abstract

Weed interference is a major factor that reduces peanut (Arachis hypogaea L.) yield in the United States (US). Peanut growers rely heavily on herbicides for weed control. Although effective, herbicides are not a complete solution to the complex challenge that weeds present. Therefore, the use of non-chemical weed management options is essential. The literature on weed research in peanut in the past 53 years in the US was reviewed to assess the achievements and identify current research gaps and prospects for non-chemical weed management for future research. More than half (79%) of the published studies were from the southeastern US. Most studies (88%) focused on weed management while fewer studies (12%) addressed weed distribution, ecology, and competitive mechanisms. Broadleaf weeds were the most frequently studied weed species (60%), whereas only 23% and 19% of the published studies were relevant to grasses and Cyperus spp., respectively. Seventy-two percent of the published studies focused on curative measures with the use of herbicides. Non-chemical methods using mechanical (5%) and preventive (13%) measures that influence crop competition and reduce the build-up of the weed seed bank, seedling recruitment, and weed seed production have received less attention. In most studies, the preventive weed management measures provided weed suppression and reduced weed competition but were not effective enough to reduce the need for herbicides to protect peanut yield. Therefore, future research should focus to develop integrated weed management strategies based on multiple preventive measures rather than one preventive with curative measures. We recommend research on mechanical weed management to focus on the role of cultivation when integrated with currently available herbicides. For successful weed management with lasting outcomes, the dominant weed communities of specific target locations should be addressed within the context of climate change and emerging constraints rather than focusing on single problematic species.