Boosting\nRice Resilience: Role of Biogenic Nanosilica\nin Reducing Arsenic Toxicity and Defending against Herbivore

The\nuse of nanoparticles is a promising ecofriendly strategy for\nmitigating both abiotic and biotic stresses. However, the physiological\nand defense response mechanisms of plants exposed to multiple stresses\nremain largely unexplored. Herein, we examined how foliar application\nof biogenic nanosilica (BNS) impacts rice plant growth, molecular\ndefenses, and metabolic responses when subjected to arsenic (As) toxicity\nand infested by the insect Chilo suppressalis. We show that BNS significantly increased shoot and root silicon\naccumulation but reduced the shoot As content by 34.7% under herbivory.\nAdditionally, BNS reduced C. suppressalis larval weight gain by 34.5 and 12.3% without and with As stress,\nrespectively. Importantly, BNS enhanced antioxidant enzyme activity\nunder As stress, herbivore attack, and combined pressures, surpassing\nthe effects of traditional silicate fertilizers. BNS ultimately increased\nrice shoot biomass by 8.2–23.4% under the respective stress\nconditions compared to the control treatment. Moreover, while As stress\nalone diminished the plant’s resistance to herbivores, BNS\napplication countered this effect by increasing detoxifying compound\n(e.g., glutathione) production and antioxidant enzyme activity. This\nstudy highlights the impact of biotic and abiotic stress interactions\non BNS-enhanced plant resilience mechanisms in rice plants, reallocating\nresources to counter heavy metal toxicity and herbivore damage in\nagroecosystems.