Effect of Spirulina platensis extract on growth potential of in vitro culture pear M.H. Abd El zaher, Sahar M. Abd El Wahab, Shreif, S. Saleh and Shaimaa M. Ramadan BIO Web Conf., 82 (2024) 01001 Published online: 03 January 2024 DOI: 10.1051/bioconf/20248201001