Effect of the seeds provenance and treatment on the germination rate and plants growth of four forest trees species of Cote d’Ivoire

The rapid rate of deforestation in Cote d’Ivoire has led to loss of plant species diversity and also threatens some commercial tree species with extinction.Some reforestation and aff orestation has been completed.However,for some species,the numbers of surviving transplants has declined.Hence,it is necessary to develop properly adapted and resilient genotypes that can eff ectively support the programs of forest restoration.In this context we evaluated the eff ects of the provenances of seeds and of various treatments on the germination rates and on plant growth of four commercial trees species(Pycnanthus angolensis,Terminalia superba,Mansonia altissima and Pterygota macrocarpa).We analyzed these parameters for seeds of three provenances(Daloa,Akoupéand Daoukro)of four species and for thirty plants aged 6 months per provenance.Time to begin germination and time to reach maximum germination were similar among species,and were not infl uenced by either treatment or provenance.Untreated seeds and those soaked for 24 and 48 h in water at room temperature yielded the highest germination rates,irrespective of species or provenance.The one exception was P.angolensis,for which no germination was recorded.Within species,some provenances produced higher germination percentages than did others.No clear relationship was computed between the germination rate and the morphometric characteristics of the seeds which varied signifi cantly between provenances.Plant growth and morphological variability also depended greatly on provenance.Genetic factors might be implicated,therefore provenance trials should be undertaken and evaluated.Furthermore,molecular analysis should be undertaken to confi rm the implications of genetic factors and allow for genetic selection.

Maternal environment and seed size are important for successful germination and seedling establishment of Pterocarpus erinaceus (Fabaceae)

Seed size and the growth environment are important variables that influence seed germination, growth and biomass of seedlings and future tree harvest and should thus be taken into account in agroforestry and reforestation programmes for endangered species like Pterocarpus erinaceus. In the present study, to assess seedling germination and vigour in P. erinaceus as a function of seed size in two environments, 1080 seeds and 360 seedlings were evaluated at two separate sites in Côte d'Ivoire. The results show that large seeds had very high germination rates (up to 100%) and produced more vigorous plants better able to adapt to climate change. The maternal environment and seed size had a significant influence on seed germination (P < 0.05) and seedling development (P < 0.05) and biomass (P < 0.05). Seedlings were most successful at the site with a humid tropical climate (Daloa). Seedling leaves had the same resistance regardless of seed size and study site, but leaf moisture content was more stable in seedlings grown from medium and small seeds. These results will help guide conservation strategies for the species and are key factors for rural populations, loggers, and forest management structures for the silviculture of this species.

Correction to:Maternal environment and seed size are important for successful germination and seedling establishment of Pterocarpus erinaceus(Fabaceae)

In the original publication,the year mentioned in the references 1 and 4 of the document have two date errors.The first reference is 2021 and not 2020:Adji BI,Akaffou SD,Kouassi KH,Houphouet YP,Duminil J,Sabatier S(2021)Bioclimate infl uence on seed germination and seedling morphology parameters in Pterocarpus erinaceus Poir.,1804(Fabaceae).International Journal of Environment,Agriculture and Biotechnology 6(3):2456–1878.

Influence of Different Environments on Germination Parameters and Seedling Morphology in <i>Khaya senegalensis</i>(Desr.) A. Juss (Meliaceae)

Khaya senegalensis is one of the largest and most majestic trees in Africa. Overexploited for its precious wood and medicinal values, the natural stands of this species are in danger of extinction in Cote d’Ivoire. Its sustainable management through regeneration techniques and assessment of its degree of adaptation to the changing climate is necessary. The aim of this study is to evaluate the effect of different environments on seedling germination and development in Khaya senegalensis. A total of 2160 seeds from different mother plants and 540 individuals from seed germination were selected and evaluated. The trials were conducted on three sites that were distinct by their microclimate (two nurseries in Cote d’Ivoire and one greenhouse in France). Analysis of variance showed that germination and morphology parameters were not influenced by the characteristics of the mother plants used (p > 0.05), but rather by the study sites (P < 0.05). The stable and controlled greenhouse climate was more advantageous for latency time (12.66 ± 0.80 days), germination delay (16.96 96 ± 0.54 days), germination speed (19.66 ± 2.95 days), germination duration (10.83 ± 2.27 days) and germination rate (88.88 ± 7.97) with more vigorous sowing than the other two sites. The results showed in general that the higher the height of the seedlings, the thicker the diameter of the seedlings (r = 0.796) and the higher the number of leaves (r = 0.946). This savannah species is native to the arid zones of Africa, but this study highlighted its adaptive potential to changing and different climates. These results are decision support tools for the regeneration of native pioneer forest species with high agroforestry potential and socio-economic importance such as Khaya senegalensis. This study could be extended to other species in order to restore disturbed ecosystems.