Ratio of Somaclonal Variation and the Phytohormonal Content of Citrus× latifolia in Three In Vitro Culture Systems

Citrus fruits are the most consumed fruit in the world and Mexico is the first producer of Persian lime. Prized for their larger size, less intense acidity, and absence of seeds, the fruits are used both for fresh consumption and industrial use. However, they present a number of phytosanitary problems and there is a great demand for disease-free plants. The present work aims to identify an in vitro culture system for the propagation of Persian lime, which allows obtaining of healthy and vigorous clones and ensures their genetic stability in subcultures. The effect of three in vitro culture systems and subcultures on the somaclonal variation of Persian lime (Citrus?×?latifolia)was analyzed using ISSR (inter simple sequence repeat)markers. Shoots of 0.5 cm in length were formed and multiplied in three in vitro culture systems in Murashige and Skoog medium supplemented with 1.0 mg L?1 6-benzylaminopurine and 0.5 mg L?1 kinetin. After 30 days, the number and length of each axillary shoot, as well as the concentration of phytohormones, were quantified. The RITA® system had the highest number of 3.8 shoots in the third subculture and the lowest somaclonal variation of less than 10.24 percent, with an increase in the concentration of phytohormones 6-benzylaminopurine and kinetin. The semisolid culture system had the highest percentage of variation of 26.5 percent in the eighth subculture.