تأثير الري بمياه مالحة في بعض الخصائص الجذرية للريزوسفير و أثرها في إنتاجية محصولين علفيين في ظروف حوض الفرات الأسفل

الملخص EN

The research was carried out at two successive growing seasons (2006-2007) in the 3rd Mry’iya experimental site which belongs to the General Commission for Scientific Agricultural Research.

The research purposes were to determine the response of some root traits (e.g.

weight, spread, and length) in rhizosphere zone to some productivity criteria of barely (var.

ACSAD 176) and sorghum (var.

Izraa7) forage crop upon irrigation with 3 water salinity levels («F» ECiw= 0.7 dS/m, «S1» ECiw= 6.0 dS/m, and «S2» ECiw= 12.0 dS/m).

The statistical analysis of barley root weight did not show significant difference between F (2.8 ton/ha) and S1 (2.1 ton/ha) treatments.

However, the difference was significant between F and S2 (0.6 ton/ha) treatment at 5% confidence limit.

Concerning barley root length, no significant difference was recorded between F (2247 m/ha) and S1 (1827 m/ha).

However, F treatment significantly surpassed S2 (714 m/ha) at 5% confidence limit.

Grain weight decreased with increasing salinity.

Where, F treatment (2.2 ton/ha) significantly surpassed S2 (1.17 ton/ha) at 5% confidence limit and no significant difference was recorded between F and S1 (1 .57 ton/ha).

In sorghum, a significant decrease in root weight was observed with increasing salinity and F treatment (3.5 ton/ha) significantly surpassed S1 (2.3 ton/ha) and S2 (1.6 ton/ha) at 5% confidence limit, and root length of F treatment (1767 m/ha) significantly surpassed S1 (1 246 m/ha) and S2 (796 m/ha) at 5% confidence limit.

Moreover, sorghum fresh weight decreased by increasing water salinity to 69% using S1 water salinity, and to 40% using S2 water salinity.

Using fresh water «F» leached the salts from the profile, where the ECe decreased by the end of the tow seasons, while salts accumulated in the deep soil upon irrigation with S1 water, and salts accumulated in all depths upon irrigation with S2 water, where ECe increased to classify the soil with saline class.