Effect of glutamine and arginine on growth of Hibiscus moscheutos “in vitro”

Nitrogen is the most essential element for plant growth and development. Amino acids, serving as the main organic nitrogen source in tissue culture media, provide for shoot and root elongation. Glutamine has been widely used in tissue culture for dedifferentiation and re-differentiation processes. Experiments were conducted to assess the effects of glutamine in comparison to some commonly used plant growth regulators (PGRs) on the growth of Hibiscus moscheutos propagated via tissue culture. An initial study suggested that 10 mg L-1 glutamine in MS basal medium was optimal for shoot elongation. At this optimal rate, glutamine showed superiority over other PGRs. No difference was found between glutamine treatments and the control in a later study. When comparing glutamine with arginine, shoots cultured on media with arginine displayed slightly greater growth. With arginine containing two extra nitrogen groups in its molecular structure, the higher percentage of nitrogen may have resulted in improved growth.