Determination of the optimal conditions for mutagenesis induction in a commercial Arabica coffee variety.

Abstract

Abstract Low genetic diversity and autogamous reproduction limit genetic improvement of Coffea arabica L. As a consequence, susceptibility to biotic and abiotic stresses increases. Induced mutagenesis is an alternative strategy for increasing genetic variability and for the development of varieties tolerant or resistant to biotic and abiotic factors. In the present study, the effect of three mutagenic agents (NaN3, EMS and 60Co gamma-rays) on survival of Arabica coffee zygotic embryos was evaluated. The zygotic embryos were immersed for 10 min in a solution of NaN3 (0, 2.5, 5.0, 7.5, 10.0, 12.5, 15.0 and 20.0 mM) or for 2 h in a solution of EMS (0, 0.5, 1, 1.5, 2, 4 and 6% v/v) or irradiated with 0, 20, 40, 60, 80 or 100 Gy. As the concentration or dose of the applied mutagen increased, survival decreased. The LD50 values for sodium azide, EMS and 60Co were 12.5 mM (51.6%), 1% v/v (48.3%) and 40 Gy (50.0%), respectively. Our results indicated that coffee zygotic embryos are suitable for chemical and physical mutagenesis and this offers an alternative for the genetic improvement of agriculturally important traits in coffee.