SELECTION OF MUTANTS IN CENTIPEDEGRASS WITH DWARFISM AND INCREASED STRESS RESISTANCE INDUCED BY GAMMA-RAY RADIATION

摘要

In order to generate new breed lines of centipedegrass [Eremochloa ophiuroides (Munr) Hack.] for reduced management costs of turfgrass,gamma-ray irradiation was used for induction of mutants from common centipedegrass.Seeds were irradiated by gamma rays,and three mutant lines (22-1,22-2,and 22-3) were isolated through evaluations in the greenhouse and field.Mutant 22-2 showed dwarfism with decreased canopy height,internode length,and leaf length.Mutants 22-1 and 22-3 showed no evident alteration in morphological characteristics,but elevated resistance to chilling and drought,with lower ion leakage under chilling stress,or lower ion leakage and higher relative water content (RWC) under drought stress.Mutant 22-3 had higher fall quality and earlier spring green-up in spring compared to other tested mutants and wild type controls.It is suggested that the useful traits of the mutants need to be further tested in practical use for decreased mowing or irrigation frequency,or increased turf quality during overwintering.