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EFFECT OF SOME AMINO ACIDS ON THE PHYSIOLOGICAL CHARACTERISTICS OF
MAIZE PLANT UNDER SOIL SALT STRESS CONDITIONS IN EGYPT AND TUNISIA
ground, then sieved through (2 mm) sieve. Plant samples of maize
crop were collected at milk stage “120 DAS”.
2.2. Analytical methods.
2.2.1. Water analysis
Hydrogen ions activity (pH value), electrical conductivity (EC),
total dissolved salts (TDS) calculated from EC values and total al-
kalinity (mg.l-1) were determined according to APHA (2012); so-
dium adsorption ratio (SAR, meq.l-1) (Suarez (1981). Na+ and K+
ware determined by flame photometer. Ca++ and Mg++, by titrimet-
ric method using (EDTA). Soluble anions (Cl-, HCO3-, CO3= and
SO4=) were analyzed using ion chromatography (IC) model DX-
2500. Water samples analysis were carried out according to stan-
dard methods for examination of water (APHA, 2012). Guidelines
to emphasize the long-term influence of water irrigation quality were
adopted according to FAO (1985).
2.2.2. Soil analysis
Particle size distribution was determined using pipette method
as described by Richards (1954). Soil extract (1: 2.5) was prepared.
Organic matter (O.M.) %, using the method of by Jackson (1973).
Calcium carbonate (CaCo3) %, using the Collin’s Calcimeter meth-
od (Wright, 1939). Available macronutrients [phosphorus (P) and
potassium (K)] using the atomic absorption spectrophotometer (Ber-
kin- Elemer 2380) were determined as described by Soltanpour and
Schwab (1977) and Lindsay and Norvel (1978). Total nitrogen (N)
was determined by the modified macro- kjeldahl technique as out-
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