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Various treatments can be used to break physical dormancy (PY, i.e. water-impermeable seed coat) of legume species, but the effects of these treatments on seedling growth are of great importance in the success of afforestation projects. Our aims were to determine the effects of 20 PY-breaking treatments on (1) germination of Gleditsia caspica (Caspian locust) seeds and (2) seedling growth. Five germination and nine seedling growth and morphological traits were studied. Immersion in concentrated sulfuric acid (98%) for 60 minutes was optimal for all germination traits and for all seedling traits except root length. After seed coat removal or treatment with sulfuric acid (for 45 to 120 minutes), 99–100% of the seeds germinated, but seedling growth traits after 5 months were significantly lower in the former than in the latter treatment. Other treatments (e.g., different periods of exposure to cold water, boiling water, and KNO3) did not significantly increase germination or improve seedling growth. Thus, despite incurring adverse environmental impacts, sulfuric acid treatments have the best potential to break seed dormancy and produce high-quality seedlings (in terms of shoot length, root and shoot mass, root area, leaf number and area and collar diameter) of Caspian locust.

Tolerance to flooding is crucial when thinking in promissory species for restoration of ecosystems prone to suffer soil water excess. In this study, we tested the flooding tolerance of two-years-old seedlings of Chestnut-leaved oak (Quercus castaneifoliaC.A.Mey.) to determine whether it can be recommended for use in wetland restoration programs. Seedlings ofQ. castaneifoliawere subjected to three treatments: (1) control (C), (2) flooding for 60 days followed by a 42-day recovery period (F + R) and (3) continuous flooding for 102 days (F). Physiological performance, plant morphological changes and biomass accumulation were assessed. Results showed that, although net photosynthetic rates, stomatal conductance and transpirationdecreased withprolonged flooding, when flood waters were removed, plants were able to recover their physiological activity (49–80% compared to controls). By contrast, when plants were continually flooded, their physiological activity decreased as well as the leaves experienced precocious senescence and wilting. Biomass responses paralleled physiological responses: leaf and root biomass were 42–49% higher under F + R treatment than under continuous flooding, and all plants under the F + R survived. Therefore,Q. castaneifoliaappears as a promising species to be further studied when thinking re-vegetation ofriverine areasand othertemporarily flooded wetlands. [ABSTRACT FROM PUBLISHER]

This paper reports the floristic survey on the Salaheddinkola forests (Nowshahr). These forests posses high variations in elevation ranges and special physiographic properties, which form the growth platform for most of the typical Hyrcanian forest species. The floristic-physiognomic investigation of the region was performed using field-walk procedure and revealed 237 plant species belonging to 196 genera and 85 families. The important families were Asteraceae, Poaceae, Rosaceae, Lamiaceae and Fabaceae with 23, 20, 14, 13 and 10 species, respectively which represented 33.17 percent of the total species. According to Raunkaiaer method, Cryptophytes (28.7%), Hemicryptophytes (27.5%) and Phanerophytes (22.5%) were the most important structure groups of the local biological spectrum followed by Therophytes (17.7%) and Chamaephytes (3.4%) Chorotypes. According to Zohary, most of the identified species belonged to Euro-Siberian and Pluriregional regions with 79 (33.6%) and 62 (26%) taxa, respectively. [ABSTRACT FROM AUTHOR]