  We consider the effective model of $H=-J_{1}\sum_{<i,j>}\mathbf{S}_{i}\cdot
\mathbf{S}_{j}-J_{2}\sum_{<i,j>}(\mathbf{S}_{i}\cdot \mathbf{S}_{j}) ^{2}$,
describing the Mott insulating phase with odd number of spin-1 bosons in
optical lattices ($J_{2}>J_{1}>0$). In terms of an SU(3) boson representation,
a valence bond mean field theory is developed. In 1D, a \textit{first-order}
quantum phase transition from a spin singlet to a spin nematic phase with
\textit{gapful} excitations is identified at $ J_{1}/J_{2}=0.19833$, while on a
2D square lattice a spin nematic ordered phase with gapless excitations
prevails. In both 1D and 2D cases, we predict that the spin structure factor
displays dominant antiferromagnetic fluctuations, while the quadrupole
structure factor exhibits strong ferroquadrupolar correlations.
