Seed germination requirements and responses to salinity and water stress of Centaurea eriophora

Abstract

Centaurea eriophora L. (Asteraceae) is a rare annual plant, found in some Mediterranean regions and requiring conservational measures. The present study was carried out to highlight the species germination behavior under two controlled environmental constraints: salt and water stress. Achenes collected on Mount Tessala (North-West Algeria) were germinated under a water potential gradient (0 to –2.45 MPa) induced by different concentrations of polyethylene glycol and under different concentrations of NaCl (0 to 102 mM). The experiments were conducted at constant temperature. The obtained results showed a high significant effect of salinity and water stress, especially on final germination percentage, while the highest germination (85%) was obtained at control conditions in both of the tests. Under salinity and water stress conditions, there was a significant deterioration in most germination parameters, particularly a lower final germination percentage. The tolerance thresholds for salinity and water deficit were 68 mM and –1.2 MPa respectively. Beyond these values, seed germination of C. eriophora was completely inhibited. The sensitivity of C. eriophora achenes to environmental pressures should be considered in the long-term effective conservation plans.

Floral Richness And Seasonalityof Phytodiversity In The Tessala Mountains, Western Algeria

“…These results are confirmed by several authors, such as Daget and Poissonet (1997, 1991, 1980, and (Floret et al, 1990). Who reported the relationships between the distribution of biological and bio-morphological types on the one hand and environmental factors, in particular the climate (precipitationand temperature) as well as altitude, slope, and substrate type, and have a stable forest model (Xuan Minh, 2022;Bouker et al, 2022).…”

“…These variations in biological spectra are mainly related to local variations in bioclimatic parameters and multiple pressures exerted by humans and animals. They reflect the relationship between the dominant biological types of a spectrum, the degree of environmental degradation, and the constraints associated with each singular medium (Verlaque et al, 2001;Latreche and Mehdadi, 2006;Bouker et al, 2022).…”

“…Thus, climatic rigors favor the development of short-cycle annual and perennial herbaceous species at the expense of generally more demanding perennial woody species, as regards water and trophic requirements (Aboura, 2006). During the wet seasons, an explosion of germination of annuals is noticed in all the arid zones of north Africa (Djebbouri and Terras, 2019), while the woody well adapted to the aridity are slowly but quite irremediably influenced by the disturbance (Bouker et al, 2022 ;Bonet, 2004;Ni-J, 2003).…”

“…Its environmental and socio-economic role deserves to be noted and studied. This massif is home to plant diversity of particular interest, favorable to regeneration after fires, and overgrazing makes this area a natural forest (Saidi et al, 2016;Bouker et al, 2022). Much work has been done on the Tessala Mountains based on the knowledge and degradation of phytodiversity (Ferka-Zazou, 2006;Chérifi et al, 2011;Bachir-Bouiadjra, 2011;Saidi et al, 2017).…”

Germination Responses of Ruta montana (L.) L. Seeds From Tessala Mount (Northwest of Algeria) to Different Controlled Environmental Conditions

“…These factors can also impact their germination, and therefore their establishment in their natural habitat (Nedjimi, Zemmiri, 2019;Benadjaoud et al, 2022;Bouker et al, 2022;Hafidou et al, 2021).Within the framework of the creation of seed banks, this will make it possible to know the optimal conditions for the cultivation of plants intended for the reinforcement of natural populations in decline. Indeed, it is reported in some works that temperature, light, salinity, and soil water potential are the most important environmental factors that affect germination, growth, development, and distribution of plants (Kogeret al, 2004;El-Keblawy, Al-Rawai, 2006).…”