Influence of temperature and salinity on the germination of Lotus creticus (L.) from the arid land of Tunisia

Abstract

Effects of salinity, temperature and their interactions on the rate and final percentage of germination were evaluated for two populations (Msarref, Oued dkouk) of the invasive glycophyte Lotus creticus Linné, grown under arid environmental conditions of the Tunisia. Seeds that were not treated with NaCl germinated well in a wide range of temperatures. For both populations, maximum germination occurred in distilled water at 25°C and lowest germination for all salinities was at 35°C. Germination was substantially delayed and significantly reduced with an increase in NaCl to levels above 300 mm. Compared to the Oued dkouk population, final germination and germination rate of the Msarref population was completely inhibited at 300 mm NaCl. The interactive effect of temperature and NaCl concentration on final germination and germination rate was significant (P < 0.01), indicating that the germination response to salinity depended on temperature. The inhibition of Oued dkouk population seed germination at high salt concentration was mostly due to osmotic effects while ionic effects were noted at Msarref population. The germination behaviour of the Oued dkouk population would therefore imply adaptive mechanisms to saline environments, while in the Msarref population such mechanisms seem to be absent. Since seed germination is more sensitive to salinity stress than the growth of established plants, the greater tolerance to salinity of Oued dkouk population would be an adaptive feature of this population to saline environment.

Responses of Maize Varieties to Salt Stress in Relation to Germination and Seedling Growth

“…The result of confirms the results of [30], [31], in maize. The osmotic effect of salts present in the growth medium gradually decreased the germination percentage as reported by [32].…”

Influence of temperature and salinity on the germination of Limonium tabernense Erben from Tabernas Desert (Almería, SE Spain)

“…However, the recovery percentage decreased as the test temperature increased. This indicates that seed dormancy is mainly due to a reversible osmotic effect rather than an irreversible damage caused by Na + toxicity (Guma et al, 2010;Rejili et al, 2009).…”

“…Seed germination and early growth of seedlings are the most critical stages in plant population establishment under saline conditions and arid climates (Khan and Gulzar, 2003;Rejili et al, 2009). Several factors influence germination: temperature, salinity, light, soil moisture, etc.…”

Germination ecology of Rhynchosia capitata: an emerging summer weed in Asia

“…Seeds of M. invisa have the ability to germinate when exposed to a wide range of saline conditions (Chauhan & Johnson, 2008). However, germination of Lotus creticus was significantly delayed and reduced with increased NaCl to levels above 300 mM (Rejili et al, 2009). Another factor that may negatively affect seed germination is moisture stress (Wilson et al, 1985).…”