Abiotic Stress-Induced Biochemical Alterations in Mulberry (Morus spp.) and Their Implications for Silkworm Nutrition

Mulberry (Morus spp.) is the primary host plant and the sole food source for the silkworm (Bombyx mori) making its leaf quality a critical determinant of silkworm growth, cocoon yield and silk quality. However, mulberry cultivation frequently encounters abiotic stresses such as drought, salinity, high temperature and nutrient deficiencies which significantly affect plant physiological processes and metabolic functions. These stresses disrupt photosynthesis, nutrient assimilation, and metabolic balance leading to substantial alterations in leaf biochemical composition. Key biochemical constituents including proteins, soluble carbohydrates, amino acids, phenolic compounds, vitamins and antioxidant molecules undergo quantitative and qualitative changes under stress conditions. Such biochemical modifications influence the nutritional value of mulberry leaves and subsequently affect silkworm feeding efficiency, larval growth rate, digestive metabolism, cocoon weight, shell ratio and overall silk productivity. Additionally, stress-induced accumulation of osmolytes and activation of antioxidant defense systems in mulberry represent important adaptive responses but may also modify leaf palatability and nutrient availability for silkworms. Understanding the physiological and biochemical responses of mulberry to abiotic stresses is therefore essential for sustaining leaf quality and maintaining sericultural productivity under changing climatic conditions. This review summarizes current knowledge on mulberry stress-induced biochemical alterations and their implications for silkworm performance, while also highlighting future research directions for developing stress-resilient mulberry varieties and sustainable sericulture systems.