@article {7322,
	title = {Germination Kinetics in Two Acacia karroo Hayne Ecotypes under Salinity Conditions},
	journal = {Open Access Library Journal},
	volume = {4},
	year = {2017},
	pages = {1-11},
	abstract = {
	Acacia karroo Hayne is the most important woody invader of grassland in South Africa, and is one of the fastest-growing acacias, and produces high density wood. This study aims to compare the germinative behaviour of A. karroo seeds collected from two ecotypes geographically and climatically different (Coastal and Steppic area) in salt stress. The seeds were exposed to saline stress conditions by increasing concentrations of sodium chloride (NaCl) varying from 0 to 50, 100, 150, 200, 250, 300, 400 and 600 mM. Germination was estimated by the daily rates and the final germinated seed rate during a period of 21 days in Petri dishes at 25oC (5 replicates of 20 seeds). The emergence of seedlings was appreciated by their overall length. The results revealed the existence of a significant variation (p \&lt; 0.001) between the two seed



	sources. Indeed, those collected from an arid ecotype were most tolerant at higher sodium chloride concentrations. The response to salinity stress varied in time with NaCl concentration and seeds origin which could be attributed to intraspecific variations resulting from the natural selection of the same species.



	Under 400 mM of NaCl, 20\% of germination was obtained from the coastal seeds against 66\% from the steppic seeds. The repeated measures analysis of variance also revealed a significant effect of factors {\textquotedblleft}Concentrations of NaCl, ecotypes, time of germination and their correlation{\textquotedblright} on the kinetics of germination.

},
	url = {https://doi.org/10.4236/oalib.1103319 },
	author = {Abdenour Kheloufi and Abdelmalek Chorfi and Lahouaria Mounia Mansouri}
}
