Bio-Efficacy of Chrysoeriol7, a Natural Chemical and Repellent, against Brown Planthopper in Rice

Abstract

Brown planthopper (BPH, Nilaparvata lugens Stal.) is the most damaging rice pest affecting stable rice yields worldwide. Currently, methods for controlling BPH include breeding a BPH-resistant cultivar and using synthetic pesticides. Nevertheless, the continuous cultivation of resistant cultivars allows for the emergence of various resistant races, and the use of synthetic pesticides can induce environmental pollution as well as the emergence of unpredictable new pest species. As plants cannot migrate to other locations on their own to combat various stresses, the production of secondary metabolites allows plants to protect themselves from stress and tolerate their reproduction. Pesticides using natural products are currently being developed to prevent environmental pollution and ecosystem disturbance caused by synthetic pesticides. In this study, after BPH infection in rice, chrysoeriol7 (C7), a secondary metabolite that induces resistance against BPH, was assessed. After C7 treatment and BPH infection, relative expression levels of the flavonoid-related genes were elevated, suggesting that in plants subjected to BPH, compounds related to flavonoids, among the secondary metabolites, play an important role in inducing resistance. The plant-derived natural compound chrysoeriol7 can potentially thus be used to develop environmentally friendly pesticides. The suggested control of BPH can be effectively used to alleviate concerns regarding environmental pollution and to construct a relatively safe rice breeding environment.

A novel transcriptional repressor complex MYB22–TOPLESS–HDAC1 promotes rice resistance to brown planthopper by repressing F3′H expression

“…Moreover, flavonoids and their biosynthetic pathway‐related genes are involved in multiple complex functions related to rice–BPH interaction. For example, chrysoeriol 7 and eriodictyol can increase rice resistance to BPH, while schaftoside can inhibit BPH growth by interacting with the native NICDK1 protein (Hao et al ., 2018; Chen et al ., 2022; Kim et al ., 2022). F3H positively regulates BPH resistance, but F3′H negatively regulates BPH resistance; additionally, these two genes are involved in multiple reactions in the flavonoid biosynthetic pathway (Dai et al ., 2019; Liu et al ., 2021; Chen et al ., 2022).…”

“…Moreover, flavonoids and their biosynthetic pathway-related genes are involved in multiple complex functions related to rice-BPH interaction. For example, chrysoeriol 7 and eriodictyol can increase rice resistance to BPH, while schaftoside can inhibit BPH growth by interacting with the native NICDK1 protein (Hao et al, 2018;Chen et al, 2022;Kim et al, 2022).…”

Holistic Pest Management Strategies in Tropical Plant Species

“…Neem seed kernel extract (NSKE) 5% and neem oil 3% were effective against brown plant hopper, as were botanical powder formulations using NSKE, Vitex negundo, Prosopis juliflora, and Ipomoea carnea leaf extract 5% for earhead insect and black bug [13]. The plant-derived natural compound chrys-oeriol7 can potentially thus be used to develop environmentally-friendly pesticides [14]. Chemical insecticides, such as carbofuran 3% CG or carbosulfan 6% G or carbosulfan 25% EC for gall midge, are applied based on need.…”

Flavonoids: Recent Advances and Applications in Crop Breeding

“…Brown Planthopper (BPH), a rice pest, causes severe damage such as viral infections, leaf blights, nutrition loss, and tissue death, all of which have a direct impact on rice productivity. Chrysoeriol7, a secondary metabolite, has been reported to be effective against BPH by establishing resistance due to the presence of an aromatic group from the flavonoid family that emanates a distinct scent that repels BPH [126].…”