An efficient callus suspension culture system for triploid bermudagrass (Cynodon transvaalensis × C. dactylon) and somaclonal variations

Abstract

An efficient callus suspension culture and regeneration system in a triploid bermudagrass (Cynodon dactylon × C. transvaalensis cv. Tifeagle) was studied in this report. Proline improved callus proliferation, but had no effect on regeneration. 0.6–1.2 mg l−1 BA improved regeneration, but higher concentrations of BA (≤1.2 mg l−1) resulted in the production of rootless plantlets. The embryogenic calli were able to proliferate continuously for at least 2 years with regeneration ability through the established suspension culture system. Observations with scanning electron microscope and light microscope showed somatic embryogenesis during the regeneration. Somaclonal variations were observed in regenerated plants. More than 2000 regenerants were screened for drought tolerance in the greenhouse, from which seven lines appeared to have increased drought tolerance relative to their parental variety. It is suggested that somaclonal variation in triploid bermudagrass offers an effective tool for its breeding.