Agroecological test of Jerusalem artichoke (Helianthus tuberosus L.) in Tajikistan

Relevance. The Republic of Tajikistan is a mountainous country, 93% of whose territory is occupied by mountain ecosystems. The vertical zonation where it is possible to grow crops extends at altitudes from 350 to 4000 m above sea level. Taking into account the growing population of the republic, scientists are faced with the task of finding and implementing innovative ways and methods of obtaining the maximum volume of necessary products and biological mass per unit area while maintaining and increasing the fertility and quality of land and soil resources. Among the agricultural crops that could in the future provide high biological mass with an energy component per unit area of agricultural land include the Jerusalem artichoke plant (Helianthus tuberosus L.). Material and Methods. In various agro-ecological conditions of Tajikistan, collection material of Jerusalem artichoke (more than 25 varieties) was studied in order to determine its production potential and further introduction in various ecological zones of the republic. Jerusalem artichoke plantings were carried out in the Southern (Vaseisky, Vakhsh and Muminabad districts, located respectively at an altitude of 460, 600 and 1200 m above sea level), Central (Dushanbe, Kanask zone, at an altitude of 840 and 2560 m, respectively) and Eastern (Rasht and Lyakhsh areas located respectively at an altitude of 1800 and 2000 above sea level) in Tajikistan. In the conditions of Tajikistan, the soils mainly belong to the following types: light gray soils, typical gray soils and mountain carbonate soils. Results. It has been established that the productivity of Jerusalem artichoke varieties varies significantly depending on vertical zonation and this is mainly due to the influence of air temperature. The yield of Jerusalem artichoke largely depends on the altitude above sea level and the sum of effective temperatures. The yield of Jerusalem artichoke tubers in various agro-ecological growing conditions ranges from 10 to 63 t/ha, and the total biological mass from 30.8 to 175.7 t/ha. A relatively high yield in our experiments was obtained in the conditions of the south of Tajikistan (at an altitude of 460 m above sea level). Here, the yield of Jerusalem artichoke tubers was 63 t/ha, and the total biological mass was 175.7 t/ha. Conclusion. In the conditions of Tajikistan at altitudes from 460 m to 2560 m above sea level, the average yield of the total biomass of Jerusalem artichoke is 91.8 t/ha, which can be an important bioresource for supporting the forage base in livestock farming, as well as a food product (tubers) for the population. By widely cultivating Jerusalem artichoke on various types of soil, it is possible to significantly increase the economic return of land resources in the Republic of Tajikistan.