The structure of the segetal flora of field crops in the steppe zone of Krasnodar Territory

A comparative analysis of the species composition of the segetal flora of the surveyed steppe zone and the segetal flora of the entire Krasnodar Territory based on the materials of numerous scientific publications is presented. The main part of the floristic spectra of both segetal florae coincides in the composition of the 10 leading families, which attests to their unity. The leading families in the compared lists are Asteraceae Dumort., Poaceae Barnhart, Fabaceae Lindl., and Brassicaceae Burnett. Floristic homogeneity of the weed species compositions between the segetal floras in the areas under different types of field crops is considered. Besides, species with a high degree of permanency in the agrocenoses of each field crop have been identified. These species are objects of phytosanitary risk for a number of field crops or some of them in the steppe zone of Krasnodar Territory. The most common weeds in the fields of all surveyed crops are field bindweed ( Convolvulus arvensis L.), common ragweed ( Ambrosia artemisiifolia L.), bristly thistle ( Cirsium setosum (Willd.) Bess.), and cockspur grass ( Echinochloa crusgalli (L.) Beauv.). Information about the predicted widespread species in the fields under a certain crop will make it possible to plan the volume of production or purchase of protective means focusing on groups of dominant species, and anticipate possible changes in the reformatting of the acreage structure, violations of the reclamation system and crop rotation schemes, etc.