  We have predicted the difference in inclusive cross sections on
pseudorapidity in ${\rm d}\sigma^{p\bar{p}}/{\rm d}\eta$ and ${\rm
d}\sigma^{pp}/{\rm d}\eta$ interactions at $\sqrt{s}=900$~GeV. Their ratio
$R=\left({\rm d}\sigma^{p\bar{p}}/{\rm d}\eta\right)\left/\left({\rm
d}\sigma^{pp}/{\rm d}\eta\right)\right.>1$ in the whole pseudorapidity range.
On the basis of AGK theorem we show that the ratio of inclusive cross sections
of $pp$ and $p\bar{p}$ at $\sqrt{s}=900$~GeV in the region of low transverse
momenta $p_\perp$ up to 2~GeV $\left(\frac{1}{2\pi p_\perp}\frac{{\rm
d}^2\sigma^{p\bar{p}}}{{\rm d}\eta {\rm
d}p_\perp}\right)\left/\left(\frac{1}{2\pi p_\perp}\frac{{\rm
d}^2\sigma^{pp}}{{\rm d}\eta {\rm d}p_\perp}\right)\right.=R$. Experimental
measurements by the ATLAS Coll. give value $R\simeq1.2$ for interval
$|\eta|<2.5$.
  The difference in inclusive cross sections results from presence of
additional subprocess in $p\bar{p}$ -- hadrons production from decay of three
quark strings, which is absent in $pp$ scattering.
