Mulberry Leaf Metabolomics: Linking Plant Biochemistry with Silkworm Physiology and Sustainable Sericulture

Abstract

Mulberry (Morus spp.) leaves constitute the exclusive food source for the domesticated silkworm (Bombyx mori), making their biochemical composition a critical determinant of silkworm growth, cocoon characteristics and silk productivity. Recent advances in plant metabolomics have enabled comprehensive profiling of metabolites present in mulberry leaves, providing deeper insights into the biochemical factors influencing leaf quality and insect nutrition. Mulberry leaves are rich in diverse primary metabolites, including amino acids, soluble sugars, organic acids and proteins, which are essential for silkworm metabolism and silk protein synthesis. In addition, secondary metabolites such as phenolics, flavonoids and alkaloids contribute to plant defence mechanisms and influence silkworm feeding behavior and physiological performance. Environmental conditions, including drought, salinity, temperature fluctuations and nutrient availability, significantly alter the mulberry leaf metabolome, thereby affecting larval development, cocoon weight, shell ratio and filament length. Modern analytical platforms such as gas chromatography-mass spectrometry (GC–MS), liquid chromatography–mass spectrometry (LC–MS) and nuclear magnetic resonance (NMR) have facilitated the identification and quantification of key metabolites associated with improved silkworm performance. Integrating metabolomics with other multi-omics approaches, including transcriptomics and proteomics, offers new opportunities to understand gene–metabolite interactions governing mulberry leaf quality. This review highlights recent advances in mulberry leaf metabolomics, its relationship with silkworm physiology and the potential of metabolomics-guided strategies for enhancing mulberry cultivation and promoting sustainable sericulture.