Basic principles of modeling the system of “genotype-environment” interaction and possible ways of using the proposed models in solving basic problems of modern genetics and breeding were discussed in detail previously (1). The most important tasks solved my means of these models are (Figure 1): evaluation of the mechanisms of transgressions and selection of parental pairs for obtaining a desired result of crossing; estimation of the contributions (eg., to productivity) of genetic-physiological systems of the parents; prediction of transgressions of breeding traits in offspring; crossing and obtaining F2 population; identification of genotypes on the base of phenotypes. These tasks are closely associated as aspects of one generalized task – effective management of successive stages of a genetic-breeding process. Development of the theory for solving this problem may open a prospect for significant advances of modern genetics .