Salinity Effects
on Survival, Growth and Morphometry of Four Egyptian Artemia
Populations (International Study on Artemia. LXVII)
N. El-Bermawi, A.D. Baxevanis, T.J. Abatzopoulos, G. Van
Stappen, P. Sorgeloos-2004
Hydrobiologia,
523 (1-3): 175-188
Abstract:
Four Artemia populations from northern Egypt,
a bisexual one from Wadi El-Natrun Lake, two coastal parthenogenetic ones
from Borg El-Arab and El-Max saltworks and an inland parthenogenetic form
from Qarun Lake, were assayed for their survival, growth and morphometric
responses measured in laboratory experiments at salinities of 35, 80, 120,
150 and 200 g l-1. The survival rate was determined using
regression analysis and analysis of covariance. The bisexual population
(Wadi El-Natrun: WN) exhibited its best survival at 80 g l-1. All
parthenogenetic strains studied performed similarly (in terms of survival)
at all salinities investigated. The population growth rates were based on
Von Bertalannfy's equation. In all salinities, WN population had the lowest
growth rate (based on K values) among all Artemia
populations tested. It is obvious that parthenogenetic populations tolerate
a broader range of salinities compared to the bisexual one. The two coastal
asexual strains had similar survival, growth and morphometric characters at
all salinities. Discriminant function analysis based on specific
morphometric parameters permitted the assignment of adult Artemia
individuals to their population of origin with a score as high as 84.6%.
Furthermore, specific morphometric parameters (such as the furcal length and
the number of setae in each furcal branch) are suitable discriminating
characters among the populations studied.
(Department of
Genetics, Development and Molecular Biology, School of Biology, Faculty of
Sciences, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece;
Tel.: +30-2-31-099-8301, Fax: +30-2-31-099-8256, e-mail of A.D. Baxevanis: tbaxevan@bio.auth.gr)