IMPACT OF IRRIGATION WATER SALINITY LEVELS ON SOME SOIL CHEMICAL PROPERTIES AND SOME FLAX VARIETIES

Pot experiments were conducted in a wire proof greenhouse at Sakha Agricultural Research Station during seasons 2010/2011 to estimate the influence of water salinity on some soil chemical properties, yield and yield components of four flax varieties.  Three water salinity levels 0.5 dS/m (W1)1.94 dS/m (W2) and 3.75 dS/m (W3), four flax varieties of Sakha1, Sakha2, Escelna and Elona and three levels of phosphorus fertilizers; without fertilizers (P₀) 0, 15.5%p₂O₅ (p₁) and 22.5%p₂O₅ (p₂) were applied in pots which filled with 9 kg of non saline clay soil
The obtained results could be summarized as follows:
Dramatic increase of soil salinity was shown after harvesting due to increasing irrigation water salinity i.e., from 2.7dS/m before planting to 2.82, 5.68, and 10.67, dS/m with W1, W2, and W3, respectively. As well as SAR values were increased from 4.39, before planting to4.71,6.90 and (13.35) with W1, W2 and W3 respectively.  Also, HCO^-₃, CL and Na⁺ were increased with increasing irrigation water salinity.
Irrigation water salinity significantly affected flax yield and yield components.  Flax seed yield g /pot had generally, the following sequence with different irrigation waters and phosphorus fertilizer levels
Sakha 2 >Sakha1 >Esclena > Elona .Phosphorus treatments ,geneally increased flax seeds and straw yields of the studied varieties.
Straw yield (g/pot), technical length, and 1000-seed weight were significantly decreased with increasing irrigation water salinity levels. 
Sakha 2 and Sakha1 were the highest tolerant varieties of flax to irrigation water salinity. While the varieties Esclena and Elona were the moderate ones according to FAO (1985), under the experimental conditions.