[Effect of population density on ecological characteristics of the grass moth Loxostege sticticalis L. (Lepidoptera: Pyralidae) in the gradation cycle]
We continued to study the diversity of responses of the grass moth Loxostege sticticalis L. to variations of density. We estimated the dynamics of the internal state of individuals and considered the influence of the population prehistory on ecological characteristics of the phytophage. In experiments on studying the structure of flower forms of the larval stage, we showed the dependence of the parameters of the internal state of individuals on prehistory, specifically on the conditions of life and type of individuals of the preceding generation. At the same time, comparison of the experimental results of 1991 and 1994 revealed a drift of the parameters of the reaction to variations in the grass moth population density by the structure of the larval flower forms and actual fertility of the imago. On the whole, the data obtained suggests that the studied species is characterized by a complex system of endogenous mechanisms underlying the regulation of numbers. The dynamics of environmental parameters is mediated by a cascade of endogenous rearrangements, as a result of which transition from depression to mass reproduction is realized through succession of the types of individuals in the population, when instead of a single phase, the flock phase starts to dominate.