Impact of applying salinity levels and specific anion of irrigation water on some characteristics of a calcareous soil cultivated with barley plants

Abstract EN

A greenhouse pot experiment was conducted on a newly reclaimed clay loam calcareous soil at the eastern edge of Tamia district, El Fayoum Governorate.

It was cultivated with barley (Hordeum vulgare, Giza 123) and irrigated with water of different salinity levels, i.e., 750, 1500, 3000 and 4500 mg / L, prepared from NaCl, Na2CO3 and Na2SO4 salts.

The current study aimed at identifying the response of both soil and grown barley characteristics to the total salt concentration as well as specific anion effects.

The obtained results showed pronounced increases in the values of bulk density and soil strength vs.

decreases in soil total porosity, hydraulic conductivity and available water range with increasing irrigation water salinity levels.

Also, the negative effect depends upon salinity level and specific anion, however, both NaCl and Na2SO4 salts exhibited slightly hazardous effect vs.

an extremely one for Na2CO3, may be due the formation of false soil aggregates in the first case and the destroyer effect in the later one.

The hazardous effect of the accompanied anions was arranged as follows: CO32- > Cl- > SO42-.

In general, increasing applied water salinity levels resulted also in an increase for each of soil pH and ESP vs.

decreases in the released available nutrients for grown plants.

Results indicated that the hazardous effect of applied NaCO3 solution was extended to the grown barley characteristics.

Barley vegetative growth parameters (plant height, No.

of tillers / plant, No.

of leaves / plant, leaf area / plant and leaves dry weight / plant) showed gradual decreases with increasing water salinity levels.

Also, it is evident that the relatively high soil salinity leads to an uptake inhibition of plant roots for all nutrients, due to the inability of subcellular osmotic units to adjust the relatively high osmotic pressure and ionic strength.

Similar trends were noticed for barley yield (straw and grains) and its components (No.

of grains / spike, 1000 grain weight, protein content % and nutrients uptake by plant).

It is noteworthy to mention that reductions in yield resulted from the decreases in the number of grains per spike rather than the decrease in 1000 grain weight, which seems to be almost stable against the change of the unfavourable conditions of irrigation water salinity levels.

Also, the reductions in straw yield, which amounted about 24-39 % at the highest water salinity level, were a function of the decrease in plant height in a minor magnitude due to tailoring capacity of relatively major magnitude.