Effect of some chemical and hormonal treatments on breaking of seed dormancy of some Almond species and peach (Prunus spp.)

In this investigation, the effect of different treatments on breaking of seed dormancy of almond species and peach seeds include Prunus scoparia Spach, P. haussknechtii Bornm, P. communis L. and P. persica L. was studied to determine their seed germination percentages. First, mature seeds, without endocarp were treated with two percent TMTD® (tetramethylthiuram disulphide) fungicide solution for 30 min, then were tested by hydrogen peroxide ( 0%, 0.5% and 1%), GA3 (250 and 500 mgl-1) for 24 hours and stored at 7oC for 1–10 weeks. Number of germinated seeds, germination percent (GP), mean germination time (MGT) and mean germination rate (MGR) were recorded for each species. Results showed significant difference between species according to their germination time. Prunus communis L. required the least time to break seed dormancy and germinated faster among tested species while P. persica L. required the highest period of time. Also, different concentrations of hydrogen peroxide and gibberellic acid had significant effect on breaking seed dormancy of studied species. After five weeks of stratification, seed germination percentages were 68% in Prunus scoparia (0.5% H2O2), 60% in P. communis (500 ppm GA3), 42% in P. haussknechtii (500 ppm GA3) and 34% in P. persica (250 ppm GA3) while control seeds failed to germinate.