Investigation of genetic variability in the direct regeneration population of sugarcane

Abstract

This study aimed to examine the genetic variation in sugarcane plantlets which were derived from direct regeneration. The objective of this study was to optimize the effect of different phytohormones on direct regeneration in sugarcane, and to extract and optimize DNA isolation from sugarcane plantlets for molecular diagnostics. Direct regeneration potential on different concentrations of plant growth regulators IBA, NAA, Kinetin and BAP were studied for four sugarcane clonal lines i.e. BL4, NIA-2010, NIA-2004 and Thatta-10, using five different media’s. 4 mg L^-1 IAA + 0.5 mg L^-1 2, 4-D + 1.0 mg L^-1 Kin medium resulted with best regeneration. Maximum plantlet regeneration rate was observed for Clone NIA-2010, while minimum was for Thatta-10. The best primary and secondary roots were observed when treated with 1 mg L^-1 IBA + 4% sugar, followed by 2 mg L^-1 IBA + 4% sugar. A decrease in primary and secondary number rootlets of NIA-2004, Thatta-10, BL4 and NIA-2010 soma clone was observed with increasing IBA concentration (4 mg L^-1 IBA + 4% sugar). Development of chlorophyll mutants affirmed that direct regeneration of genetic fidelity cannot be maintained, but is a good source of exploring existing aneuploidy. It was concluded that MS medium containing 4 mg L^-1 IAA + 0.5 mg L^-1 2,4-D + 1.0 mg L^-1 Kin proved to be the rapid method for obtaining plantlets through direct regeneration. The RAPD study confirmed the genomic difference in plantlets population which were obtained through direct regeneration. The results of this research will help in the identification of superior parental lines for hybridization, which can be used to produce better sugarcane varieties.

Keywords: BAP; direct regeneration; IBA; RAPD; Sugarcane

http://dx.doi.org/10.19045/bspab.2023.120096