Seed Germination and Seedling Growth of Robinia pseudoacacia Depending on the Origin of Different Geographic Provenances

Abstract

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.

From Seed to Seedling: Influence of Seed Geographic Provenance and Germination Treatments on Reproductive Material Represented by Seedlings of Robinia pseudoacacia

“…Morphological traits noted for black locust seeds indicated that the origin was relevant for the current investigation, with the data being quite variable [6]. The present study revealed seed traits such as thickness, length, width, and weight, which are represented as a boxplot diagram (Figure 2) consisting of the minimum and maximum range values, the upper and lower quartiles, as well as the median, to summarize the distribution of the dataset recorded.…”

“…The first treatment referred to the mechanical scarification method, using abrasive sandpaper until the tegument was visibly damaged [17]. The second type of treatment (thermal treatment) involved water-soaked seeds at different temperatures [3,6]; seeds were soaked for 10 min in water at a temperature of 100 • C, 70 • C, and 40 • C. For the third treatment, seeds were soaked in biostimulator solution (Foliplant, 0.9%) for 10 min [21]. The fourth treatment used acetone (90%) solution for 10 min of seed imbibition [22].…”

“…Black locust reproduces sexually and asexually; it can propagate by seeds, spring root cuttings, or dormant sucker divisions. For breeding studies, generative reproduction is 2 of 19 taken into consideration: It produces genetic variation in the offspring generations (exploitation of variability in such a way), the seedlings have a high survival rate, and the species can easily adapt to new environments [2,6]. In its native and introduced ranges, natural regeneration of black locust is primarily vegetative; however, the species also regulates its spread on sexual reproduction, with bee-pollinated hermaphrodite flowers and prolific seed production and dispersal [7,8].…”

“…Moreover, in Europe, information on seed regeneration is insufficient for accurate species management, and germination requirements are not completely clarified [11]. In this regard, the studies that try to assemble such distinct factors (i.e., the origin of seeds and seeds features, germination treatments, seedling growth) to gain a general overview of the process of producing valuable reproductive material for the species are welcome [6]. Forest reproductive material (FRM) as a notion is generally considered to be a generic name for seeds, cones, cuttings, and planting material (planting stock) used in forest establishment.…”

Environment Modification Mediates Seed-to-seed Interactions between Dominant Species in the Yangtze River Estuary

“…Difference in germination rate and germination timing under various conditions has a significant impact on recruitment and potential competitive ability of seedlings [16,17], which then determines population distribution and community structure [18]. A great number of studies have demonstrated the effects of environmental factors (e.g., temperature, light, soil moisture and salinity) on seed germination [19][20][21][22], but few considered the biotic interactions among seeds. In field sites, seeds of different species often appear in the same place due to the dispersal by wind, tide or animals [23,24], which makes the germination process affected by neighbouring conspecific or heterospecific seeds.…”