Seed and in vitro embryo germination in aged almond

Abstract

The present study was performed to determine the best combination of some growth regulators for the in vitro germination of isolated embryos in newly harvested and aged almond seeds (stored for 1, 2, and 3 years) without cold treatment. Almond seeds were placed into perforated plastic bags and stored in a room at 1°C for 1, 2 and 3 years between 2004 and 2006. 0, 1, 2 and 3 year-old almond seeds (with shell) were sown in perlite and stratified at 4°C for 60 days in a dark room. After stratification, almond seeds were germinated at 25°C with a 16-h photoperiod. The germination percentages of almond seeds stored up to 3 years were between 86.7% and 42.7%. To determine the best combination of some growth regulators for seeds and embryo germination, only newly harvested seeds were used. Seeds with/without testa did not germinate on MS medium containing different concentrations of BAP and GA3 without cold treatment. The maximum embryo germination percentage was obtained from the media supplemented with 2.22 μM BAP+8.7 μM GA3 (85%), 4.44 μM BAP+8.7 μM GA3 (75%) and 2.22 μM BAP+2.9 μM GA3 (70%). The embryos of stored almond seeds germinated on MS medium containing either 2.22 μM BAP+8.7 μM GA3 or 4.44 μM BAP+8.7 μM GA3 without cold treatment.