Relevance. Trophic relationships along with competition and mutualism are the most basic and significant interactions in ecosystems. To develop, survive, and multiply, insects need to consume a certain amount of nutrients at a certain ratio. Food products are complex mixes of nutrients and non-nutritive substances (sometimes toxic ones): macronutrients (proteins, carbohydrates, and lipids), micronutrients (vitamins and minerals), and water. Some nutrients are essential; insects lack the ability to synthesize them in their bodies and must obtain them from their diet or through symbiosis with beneficial organisms. Identification mechanisms being well developed in the system “phytophagous insect – plant” allow insects to successfully spread, multiply, and feed on certain plant species. The complex of hydrolytic enzymes in the insect intestine is one of the main targets for plant defense responses because these enzymes determine the availability of structural compounds for phytophagous insects. For this reason, enzymes in the insect intestine play a key role in the adaptation of insects to the pest resistance of fodder plants. For instance, when proteinase inhibitors are synthesized in a fodder plant as the result of induced insect resistance the complex of enzymes in an insect intestine might change negating the effect of these inhibitors. The development of co-adaptations due to interactions among species in food chains depends on a complicated constellation of conflicting relationships between consumers and food objects. The mechanisms of this influence may be rooted in the allelochemical interactions in the system “phytophagous insect – plant recipient”. Allelopathic interactions are among the most complex interactions because they are constituted by direct and indirect effects. Plants when damaged by phytophagous insects activate defense responses, which incorporate several mechanisms, including an increase in the concentration of secondary metabolites, many of which are phenolic compounds.The aim of the work is to describe the mechanisms of relationships in the system “phytophage-plant”. Conclusion. Management of processes of intra-water divergence of insect-phytophages in agrobiocoenoses in order to prevent the emergence of races and populations of pests adapted to live on initially resistant to them plant forms is possible in compliance with the transition to a targeted selection of agricultural crops for resistance to a complex of pests.

Problems of proper nutrition and health of citizens are becoming increasingly important every year. A significant number of chronic non-communicable diseases have been observed in Russia and its regions for several years. Thus, according to the Territorial body of the Federal state statistics service for the Irkutsk region in 2017, the mortality rate from diseases of the circulatory system was 615 people per 100 thousand people, 218 people per 100 thousand people died from neoplasms. The reason for the increase in the incidence of population researchers believe the change in socio-economic structure, lifestyle and diet. At the same time, the President of the Russian Federation defined the task of achieving the average life expectancy of Russians at the level of 78 years in the may Decree of 2018. Currently, for the Irkutsk region, this figure is at the level of only 69 years and at the current rate of growth by 2024 will reach only 75 years. In this regard, we need a set of measures aimed at improving the health, living and working conditions of citizens of the country, which can be implemented, including through ensuring a normal diet of life and consumption of basic products, including vegetables, at a level not lower than the rational norms of their consumption. The article presents an assessment of the capacity and potential of the market of vegetable products on the materials of the Irkutsk region, the main producers, exporters, importers of vegetables, the forecast of shortage of vegetables. Social efficiency in achieving the proposed performance indicators will be determined by increasing the life expectancy of the population, reducing morbidity, improving the quality of life of those suffering from diseases associated with malnutrition, and the ratio of the obtained favorable social results to the costs to achieve them. Economic efficiency will be expressed by assessing the impact of the results achieved in the framework of program activities on the formation of the gross product, ensuring the dynamics of economic growth and increasing productivity, as stated in the presidential decree and Federal national projects until 2024. The practical application of vegetable demand calculations in accordance with rational consumption norms can be used in the process of marketing research to identify the potential market entry of new players or increase the production of fresh vegetables by their existing producers.

Against the backdrop of the slow recovery of the world economy from the consequences of the global financial and economic crisis, the world community is to find a new model of interaction and create new mechanisms for economic development. In the course of integrating the Chinese economy into the world economy, China is ready to assume more international responsibilities and obligations in accordance with its capabilities, including in the field of providing the population with food. The history of reforming the food market in general and the vegetable market in particular began in the PRC in 1978 from the countryside and in 2017 reached the world scale in the framework of creating international economic relations under the project "One belt – one way". The article deals with the development of the vegetable market in China, ensuring safety and high quality standards of vegetables in the country, as well as the direction of international development of China's economic relations in the course of solving the problem of providing the population with food. As a result of the research, the development of the vegetable market in China was revealed.

The population of our planet is growing every year and its growth by 2050 will exceed the potential of agriculture and will not be able to provide food security in General. This problem is the subject of the study. The article considers the existing programs of the Russian Federation aimed at supporting domestic producers of agricultural raw materials and food, ensuring the availability and quality of food in the food market. Foreign experience in the creation and implementation of programs in these areas has been studied. The article presents an assessment of the consequences of sanctions on the total cost of trade flows between the European Union and Russia. The study was carried out on the example of data on the Irkutsk region. An element of scientific novelty is the consideration of approaches to solving the problem of food security not only from the state, producers of agricultural raw materials and food, but also from its consumers – the population. Social efficiency in achieving the proposed performance indicators will be determined by increasing life expectancy, reducing morbidity, improving the quality of life of those suffering from diseases associated with poor nutrition, and the ratio of the obtained favorable social results to the costs to achieve them. At the same time, economic efficiency will be expressed by assessing the impact of the results achieved in the framework of the program activities on the formation of the gross product, increasing labor productivity and ensuring the dynamics of economic growth. The practical application of the proposed directions of improving the availability and quality of food for the population will improve the efficiency of the food market and create conditions for the formation of the state of protection of the Russian subjects from the threats of food security.

Providing the population with affordable safe food is becoming increasingly important due to the growing population of the planet, the aggravation of socio-economic relations between states, the increase in the number of environmental problems and the replacement of natural organic food with snacks, products containing artificial components and GMOs, and functional foods. The article discusses the planning of measures taken by the regional authorities to provide the population with basic types of food, the calculation of the needs of which is compiled in accordance with rational norms for the consumption of food products that meet modern requirements for healthy nutrition. On the basis of linear programming, a model of predictive provision of the population with basic types of food products for the period 2018-2020 was compiled. The data on the compiled model can be prolonged and corrected when the statistical indicators of 2016, 2017 are obtained and the planned number of population in the period under review is specified. As a result of the study, the forecasted values of the required volume of food for the population of the Irkutsk region were obtained. The basic components of the mechanism of interaction of all interested subjects of the food market and a set of conditions for the implementation of promising directions of the mechanism for the formation and implementation of food policy in accordance with the stated goals are proposed. Social effectiveness in achieving the performance indicators proposed in the work will be determined by increasing the life expectancy of the population, reducing morbidity, improving the quality of life of those suffering from diseases associated with unsustainable nutrition, and the ratio of the resulting favorable social results to the costs to achieve them, while economic efficiency will be expressed by an estimate The impact of the results achieved in the implementation of program activities on the formation of the gross product, and Vyshen productivity and ensuring the dynamics of economic growth.