Trends in agrophytocenosis caused by long-running disturnabces of agrotechnical methods

Agrophytocenosis is a dynamic structure that changes according to the grown crop, to its agrotechnical methods and climatic conditions. The changes of any factor can lead both to species composition changes and to quantitive changes of the agrophytocenosis. This research was conducted on the fields of SEI HE LPR LNAU TSMAC «Kolos» from 2009 to 2019 using the sample plot method. The correlation of weeds species diversity between 5 years before and 5 years after the disorder of agrotechnical methods (the military activities in Donbass region) showed the increasing of species composition in comparison with the pre-war period in 1,9 times. The new species appeared in the plantations that had not grown here before: Achillea millefolium L., Artemisia austriaca Jacq., A . vulgaris L., Lamium amplexicaule L., Polygonum bistorta Delarbre, Rumex confertus Wild. During the analysis according to biological groups the predominance of annual and biennial weed plants over the perennial weeds was observed. But meanwhile the diversity of perennial weed plants increased by 4, 25. Taproots plants ( Artemisia absinthium L., Carduus crispus L., Cichorium intybus L.), bulbotuberiferous plant ( Heliantus tuberosum L.) and parasitic plant ( Cuscuta campestris Yunck) appeared in the plantations. The amount of rhizome and offset weeds increased: 25 weed plant species growing in the plantations (50 % of all) were adventives ones ( Amaranthus blitoides S.Wats., A. retroflexus L., Ambrosia artemisiifolia L., Cyclachaena xanthiifolia (Nutt.) Fresen., Heliantus tuberosum L.). The highest species diversity belongs to the family Asteraceae.