Comparative in vitro Regeneration Potential of Indian Bean Genotypes from Embryonic Axis Explant
Hensi Kundariya
Department of Genetics and Plant Breeding, N. M. College of Agriculture, Navsari Agricultural University, Navsari 396 450, Gujarat, India.
Isha Mendapara
Department of Genetics and Plant Breeding, N. M. College of Agriculture, Navsari Agricultural University, Navsari 396 450, Gujarat, India.
Himani Vadodariya
Department of Genetics and Plant Breeding, N. M. College of Agriculture, Navsari Agricultural University, Navsari 396 450, Gujarat, India.
Kaushal Modha *
Department of Genetics and Plant Breeding, N. M. College of Agriculture, Navsari Agricultural University, Navsari 396 450, Gujarat, India.
Vipulkumar Patel
Department of Basic Science and Humanities, College of Forestry, Navsari Agricultural University, Navsari 396 450, Gujarat, India.
Ritesh Patel
Department of Genetics and Plant Breeding, N. M. College of Agriculture, Navsari Agricultural University, Navsari 396 450, Gujarat, India.
Shailesh Mali
Main Sugarcane Research Station, Navsari Agricultural University, Navsari 396 450, Gujarat, India.
Alok Shrivastva
Department of Agricultural Statistics, N. M. College of Agriculture, Navsari Agricultural University, Navsari 396 450, Gujarat, India.
*Author to whom correspondence should be addressed.
Abstract
Aim: To develop and evaluate an in vitro regeneration protocol from embryonic axis (EA) explants of Indian bean using four different genotypes (GP-1, GP-189, GNIB-21 and GNIB22).
Study Design: The experiment was conducted using a completely randomised design (CRD) with five replications.
Place and Study Duration: This study was conducted at the Plant Tissue Culture Laboratory, Main Sugarcane Research Station, Navsari Agricultural University, Navsari, during 2021–2023.
Methodology: Excised embryonic axes from imbibed seeds of four Indian bean genotypes were cultured on Shoot Induction Medium (SIM) containing BAP (0.5 mg/L), kinetin (0.5 mg/L), and polyvinylpyrrolidone (1 mg/L) for five days. The shoot apical meristem and plumule were then decapitated to induce multiple shoots from the cot-node region. Decapitated EAs differentiated into multiple shoots from the cot-node region on SIM. Elongated shoots were transferred to Shoot Elongation Medium (SEM) containing GA₃, kinetin, and asparagine, followed by Root Induction Medium (RIM) containing IBA (0.7 mg/L) and polyvinylpyrrolidone (1 mg/L). Rooted plants were subsequently hardened and evaluated for survival and regeneration.
Results: Significant differences among genotypes were observed for shoots per explant and shoot length. Two genotypes (GP-1 and GP-189) showed root induction from elongated shoots, with significant variation in roots per shoot and root length. Both genotypes exhibited 100% survival during hardening. The regeneration percentage ranged from 44.08% (GP 1) to 50.07% (GP 189).
Conclusion: The study successfully demonstrated in vitro regeneration of fertile Indian bean plants from decapitated embryonic axis explants. The developed regeneration protocol can serve as a prerequisite for genetic transformation and genome-editing studies in Indian bean.
Keywords: Indian bean, Embryonic axis, direct regeneration, multiple shoots