تأثير ملوحة التربة و مبيد الكلايفوسيت في إعداد بكتريا النترجة لترب مختلفة النسجة

Abstract EN

Three different soils texture ( sandy loam , loamy and clay) fertilized with Urea and treated with four concentrations of Glyphosate herbicides (0 ,50 ,75 and 100 %) of recommended dose.

Salinized level was modified using drainage water with three salinity levels4 , 8 , and16 dS m-1.

The soils were incubated for different periods to study the effect of soil salinity and Glyphosate herbicides on the number ofNitrifiers.

Three replicates with completelyrandomized design were used.

The soil samples were incubated for 3 , 6 , 9 , 12 and 15 days at 30°C to estimate the number of Nitrifiers (Nitrosomonas and Nitrobacter) .Nitrifiersnumber increased with increasing incubation period from 3 to 15 days in the clay soil as campared to loamy and sandy loamy soilwhile the number of nitrifiers decreased with increasing soil salinity.Nitrifiers number was(17.05 ×103 , 13.33 × 103 and 12.44× 103)cell.gm-1 soil at levels of 4 , 8 and 16 dSm-1 respectively.