Redox imbalance mediates entomotoxic effects of the conifer Araucaria angustifolia in Anticarsia gemmatalis velvetbean caterpillar

Abstract

The velvetbean caterpillar, Anticarsia gemmatalis is one of the most important pests of soybean crops in tropical America. By feeding on leaves, significant defoliation occurs resulting in reduced photosynthetic capacity required for plants' maintenance and growth, which subsequently can lead to crop losses and reduced agricultural productivity. Many studies have sought to look for compounds that have insecticidal effects. One class of compounds is phenolics, which are produced by plants and have been found to influence the behavior and development of defoliators, representing an important alternative approach to many synthetic insecticides. Particularly, Araucaria angustifolia is a plant rich in polyphenols, which are compounds able to alter cellular dynamics through modulating redox status. In this study, A. angustifolia extract (AAE) was added to the artificial diet of A. gemmatalis. The results demonstrated that AAE was able to reduce larval viability by inducing morphological changes and a delay in the insect's development. In addition, AAE was found to induce oxidative damage to lipids and proteins, as well as increased nitric oxide levels in A. gemmatalis larvae. AAE treatments also decreased the antioxidant defense systems, leading to a redox imbalance. The reduction in viability in A. gemmatalis was positively correlated with oxidative markers, suggesting that redox imbalance can lead to larvae's death. These results suggest that AAE possess

Comparative effectiveness of Metarhizium rileyi, novaluron, and glyphosate on immune system, development, and redox metabolism of Anticarsia gemmatalis

“…We demonstrated that the increased levels of •NO in the treatment of M. rileyi could have caused the death of the insects, through the oxidative stress mechanism, corroborating with described by Branco et al (2014Branco et al ( , 2016. •NO is potentially toxic, particularly involved with oxidative stress (Moncada & Higgs, 2006).…”

“…The latter includes a group of detoxifying enzymes such as superoxide dismutase and catalase. Previous studies have demonstrated that agrochemicals such as glyphosate (Monserrat et al, 2007;Sies, 1993) and even some natural extracts (Branco et al, 2016(Branco et al, , 2014 are able to cause an imbalance between the production of ROS and the antioxidant system, inducing entomotoxic effects by increasing oxidative stress. Oxidative damage to biomolecules, such as lipid peroxidation and protein modifications, can lead to cell death (Cobb & Cole, 2015).…”

Integrated Pest Management Strategies for Invasive Fall Armyworm

“…As the larvae mature, their population typically decreases due to cannibalistic behavior, and generally only one or two larvae can be observed per plant. Nonetheless, mature larvae can cause significant defoliation (Pogue 2002;Branco et al 2016;Horikoshi et al 2021). In uncontrolled situations, larvae can strip all green leaves within a brief period, leaving only leaf ribs and stalks that seem torn.…”