Utilizing growth retardants and osmotic agents to promote a slow growth process for in vitro conservation of bananas

Banana cultivar Nanjanagud Rasabale (AAB, Silk subgroup), native to Karnataka, India, has failed to revive its Geographical Indication (GI) tag, largely due to its high susceptibility to Fusarium wilt caused by Fusarium oxysporum f. sp. cubense (Foc). This susceptibility threatens the survival of this elite variety, highlighting the need for its conservation. One valuable biotechnological method for conserving plant germplasm is in vitro conservation. Laboratory studies were conducted to develop an effective protocol for conserving Nanjanagud Rasabale plantlets by inducing slow growth through media manipulation. This involved adding various growth retardants—such as ancymidol, paclobutrazol, abscisic acid, DMSO and osmotic agents like mannitol, sorbitol, sucrose and maltose, each at three different concentrations, to Murashige and Skoog (MS) medium. As a result, the subculture period was extended and the storage life of the cultures was prolonged through a slow growth process, without inducing any genetic variation.