Hormonal Regulation of Root Induction in Mulberry (Morus spp.): Advances and Challenges
S. A. Brindha Bharathi *
Department of Sericulture, Forest College and Research Institute, TNAU, Mettupalayam, Tamil Nadu, India.
S. Menaka
Department of Sericulture, Forest College and Research Institute, TNAU, Mettupalayam, Tamil Nadu, India.
R. Kalpana
Department of Sericulture, Forest College and Research Institute, TNAU, Mettupalayam, Tamil Nadu, India.
M. Sabarish
Department of Sericulture, Tamil Nadu, India.
G. Anusuya
Department of Sericulture, Forest College and Research Institute, TNAU, Mettupalayam, Tamil Nadu, India.
R. Durgadevi
Department of Sericulture, Forest College and Research Institute, TNAU, Mettupalayam, Tamil Nadu, India.
T. Bhuvaneshwari
Department of Sericulture, Forest College and Research Institute, TNAU, Mettupalayam, Tamil Nadu, India.
R. Nandha Kumar
Department of Sericulture, Forest College and Research Institute, TNAU, Mettupalayam, Tamil Nadu, India.
R. Moulidharshan
Department of Sericulture, Forest College and Research Institute, TNAU, Mettupalayam, Tamil Nadu, India.
*Author to whom correspondence should be addressed.
Abstract
Mulberry (Morus spp.) plays a pivotal role in sericulture as the primary food source for silkworms, and its successful propagation is essential for sustainable silkworm farming. This review comprehensively examines the physiological, molecular, and biotechnological aspects of root induction in mulberry, with a focus on hormonal interventions. Auxins such as IBA, NAA, and synthetic analogs like ABT-1 have shown significant efficacy in enhancing adventitious root formation, especially in difficult-to-root cultivars. The synergistic roles of cytokinins, gibberellins, abscisic acid, ethylene, and jasmonic acid are also explored. In addition, transcriptomic studies reveal the involvement of key regulatory genes, while enzymatic and biochemical profiles offer further insight into rooting dynamics. The paper also evaluates propagation techniques, the role of biostimulants and microbial inoculants, environmental and genetic factors affecting rooting, and the future potential of CRISPR and omics-based technologies. This review provides a consolidated platform for developing optimized, eco-friendly, and genotype-responsive propagation protocols in mulberry.
Keywords: Mulberry propagation, root induction, auxins, plant hormones, tissue culture