Sustainable development based differentiation

For sustainable development of mountain phytocenoses biodiversity it s necessary to set up systems of enviromnentally differentiated varieties of fodder crops with tolerance to extreme and destabiUzing enviroiunental conditions. Environment-evolutionary principles are becoming dominant in selection strategy of fodder crops in recent years. They are based on the theory of adaptive system of plant growing and provide for creation of geographically and environmentally differentiated varieties [1]. 

In the model proposed by Hyver Le Guyader (1990), two systems of equations are considered. In the first version, inactive p34 (i.e. cdc2 kinase) transforms into active p34, either spontaneously or in an auto-catalytic manner active p34 then combines with cyclin to yield active MPF. This situation is described by four differential equations, of a polynomial nature, in which the highest nonlinearities are of the quadratic type. In a second version of this model, governed by three kinetic equations of a similar form, the authors consider the effect of an activation of MPF by MPF itself as well as cyclin, and show that oscillations develop when the degradation of cyclin is brought about by the formation of a complex between cyclin and MPF. That study was the first to show the occurrence of sustained oscillations in a model based on the interactions between cyclin and cdc2 kinase. The type of kinetics considered for these interactions remained, however, remote from the actual kinetics of phosphorylation-dephosphorylation cycles. 

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