Some nonlinear phenomena of nonlinear resonance, chaos, stochastic resonance and stochastic chaos occur in the laser-DNA interactive system, which make DNA mutated and broken up. The laser-radiated exogenous DNA was introduced into the tomato. It is beneficial to the expression of some characters of dominant genes of the donor and the improvement of the descendents qualities of receptors. The peroxidase isoenzyme of the donor, the receptor, and their descendents were analyzed. Our result shows that the peroxidase isoenzyme zymograms of most descendents are very similar to the donor but rather different from the recepor. The similarity of isoenzyme zymograms between descendents and donor, and the expression of external characters of donor in descendents indicate that the exogenous DNA has been saccessfals introduced into the receptor with the expression of exogenous DNA in descendents.