Black locust (Robinia pseudoacacia) is recognised as a forest species of interest due to its multiple uses. The management of forest genetic resources and their efficient conservation suffer from variations in traits and start with seed germination. The aim of the current study was to investigate the germination of seeds obtained from plus trees selected in eight Romanian provenances, as well as to investigate the influence of the origin upon plants’ growth and development. Two experiments were undertaken to test seed germination: one treatment involved water-soaked seeds and heat/cold treatment, while the other treatment was based on sulphuric acid, at different concentrations (50, 70, 90%). The results were correlated with the morphological analysis of the seeds. Satu-Mare had the lowest germination rate within both treatments. Sulphuric acid did not improve seed germination as much as the heat treatment. The highest germination rate occurred for the water and temperature treatment on seeds from Bihor provenance (68.2%). The most distant provenance was Bihor, in inverse correlation with Bistrița Năsăud and grouped separately within the hierarchical dendrogram of cluster analysis based on the analysed parameters of the provenances investigated. The results demonstrated that the genotypes and environmental heterogeneity of the seed origin within the provenances may finally result in different performances.

The influence of the geographical origin of eight Romanian provenances of Robinia pseudoacacia on the characteristics of seeds, germination, and growth of seedlings in young stages of life was analyzed. Four experiments were undertaken to test seed germination (thermal treatment at distinct temperatures, mechanical scarification, acetone 90%, and biostimulator). The germination percentage showed that scarification treatment provided the best results among all treatments (41.7%). Seeds soaked in water at 100 °C provided the second-highest germination rate. Furthermore, the same two treatments also assured the highest values for the seedlings’ length. There were registered significant differences among the provenances for the analyzed characteristics, the seed germination capacity, and the growth rate of the seedlings in the first years of life. The study highlighted the resources that could ensure good quality of the reproductive forest material, which can be used in new afforestation and breeding programs. Pearson correlations and multivariate analysis provided interesting and useful information about R. pseudoacacia provenances and 13 characteristics of the seeds and seedlings, highlighting the relationship among them. The results could be of interest for the efficient use of forest genetic resources and the obtention of quality reproductive material in black locust.

The aim of this research was to investigate the influence of an electric field and gamma radiation upon the germination of spruce seeds. In order to carry out the research, spruce seeds from different provenances have been subjected to different treatments: electric field (EF) with 10 V, 30 V, and 50 V voltages and intensity of E = 266V/m, exposure time of 15 and 35 min, and gamma (G) radiation with several treatments (1 Gy-31 min, 1.5 Gy-46 min, 2 Gy-62 min, and 6 Gy-186 min). Under the influence of EF, the best results upon seed germination (80.83%) were recorded when seeds were treated with 30 V for 15 min, for all provenances investigated. Regarding gamma radiation, the highest germination percentage (87.50%) was achieved in T5_G when seeds were subjected to 6 Gy for 186 min. It was also considered the interaction between seeds origin and the different EF and G treatments applied to the seeds to induce germination and further seedlings’ development. The results obtained after seeds were exposed to gamma radiation came out on top compared to electric field treatments, both for the germination and seedlings’ height.