Author/Authors :
mohamed, m. m. al - azhar university - fac. of agric. - soils and water dept., Egypt , m.o. el - mohtasem, bella al - azhar university - fac. of agric. - soils and water dept., Egypt , abou el-khair, r. a. al - azhar university - fac. of agric. - soils and water dept., Egypt , sheta, m. h. al - azhar university - fac. of agric. - soils and water dept., Egypt