The features of the reproduction of insect phytophagous and their intra- and interspecific relationships which in major cases manage through biological rhythms and biological cycles. A deeper study of these phenomena gives a clearer description of the ecological and biological mechanisms of the dynamics of insect behavior and contributes to the creation of new methods for pests management in agrocenosis. The high correlation between the number of phytophagous and beneficial species with the influence of abiotic and other conditions the naturally rhythms of insects allows to create more effective methods of insect pest management. This article discuss the theoretical and practical aspects of bio- rhythms and photoperiodic reactions based on analyzes of the latest scientific researches of insect management mechanisms in sunflower fields and other crops. All results of analyzed literature and monitoring, give us make conclusion that the dynamics of long-term average indicators of temperature, humidity, level of hydrothermal coefficient correlates with the biology and ecology of the studied phytophagous: Agrotis segetum Schiff., Brachycaudus helichrysi Kalt. and Agriotes spp. Based on the results of observations, reproduction matrices, biological rhythms and diapause of the studied harmful species of insects were compiled in modern field crop rotation and tillages (an average for 2017-2019)
biological rhythms; reproduction; phytophagous; economic thresholds, pest management