Molecular mechanisms of CeO2 nanomaterials improving tomato yield, fruit quality, and postharvest storage performance

Abstract

Nanomaterials (NMs) have exhibited great potential for improving agriculture production and fruit storage. In the present work, 1, 10, and 50 mg kg⁻¹ of CeO₂ NMs were demonstrated to significantly promote tomato yield. Particularly, 10 mg kg⁻¹ CeO₂ NMs showed the most significant promotion of tomato yield by 83.7% as compared to the unexposed control along with advanced flowering by 10 days. This increased reproductive growth was mainly due to the accelerated organic acid and amino acid metabolism, more synthesized and transported sucrose, and upregulation of flowering promoter genes. Other than the early flowering and increased production, 10 mg kg⁻¹ CeO₂ NMs significantly increased fruit quality (content of malic acid, vitamins and flavonoids) and nutrient elemental content (Na, K, Fe, Cu and Zn). Notably, CeO₂ NMs stimulated the synthesis of waxy layers and salicylic acid pathways in fruits, and the picked tomatoes thus showed better storage capacity (greater antibacterial activity, less water loss, and increased hardness) compared to the unexposed control. Finally, the abundance of the postharvest tomato soil microbial community showed a higher mineralization rate and faster soil nutrient cycling. Taken together, CeO₂ NMs not only promoted the yield and quality of tomatoes, but also had beneficial effects on postharvest fruit storage and soil quality. The application of CeO₂ NMs could be a promising approach for sustainable agriculture.