Cultivating subtropical crops on the Black Sea Coast of Russia: ecological and agrochemical aspects

Over the past 25 years, in All-Russian Research Institute of Floriculture and Subtropical Crops (Sochi) the soil science research focused on the ecological and agrochemical parameters of tea (Camellia sinensis L.), lemon (Citrus limon), kiwi (Astinidia deliciosa) and pawpaw (Asimina triloba Dunal) cultivation in Russian humid subtropical conditions. On the basis of studying the plant needs in nutrient elements, their biological and yield removals, as well as the results of field experiments, including assessment of the effectiveness of different types and doses of fertilizers, there were developed some elements of fertilizers systems for these subtropical crops (diagnostics of plants nutrients, terms and doses of fertilizer application). Here we also reported some specific features of microbe-plant associations of subtropical crops (i.e. the composition and structure of microbocoenosis, its response to agrochemicals), which indicated their role in agroceonosis stability. The scientific concept of fertility optimization and fertilizer application (i.e. the system of approaches and criteria) was developed for the most economically significant tea crop. It provides a comprehensive individually differentiated principle of plant cultivation in the tea plantation agroecosystems, considering plant age, potential and effective soil fertility, cultivar productivity, quality of raw materials, meteorological conditions, a degree of soil agrogenic transformation, economic efficiency and environmental safety of the applied agrochemicals.