Weediness of corn for grain crops by cultivation in the stationary crop rotation and permanent crops in the Eastern Forest Steppe of Ukraine

Abstract

Goal. To determine the species composition of weed plants and their dominant role, to establish the type and level of weediness of corn crops for grain grown in stationary crop rotation and monoculture in the conditions of the Eastern Forest Steppe of Ukraine. Methods. The research was carried out by route surveys of crops in field experiments. results. Аccording to the research data in 2011—2017 in corn sowing for grain found 33 types of weedy pollinators that belonged tо 17 families and contaminants were found in corn for grain crops, of which the most common were Asteraceae (9 species), Poaceae (4 species) and Polygonaceae (4 species). There were found 25% fewer species of weed plants (24 species) in corn for grain crops in monoculture than in crop rotation (32 species). Among weed plants, spring early and late species prevailed (65.6% — in crop rotation; 62.5% — in monoculture). The main types of weeds (occurrence of the species from 78 to 100%) in crop rotation were Setaria glauсa (L.) Beauv., Echinochloa crus-galli (L.) Roem. et Schult., Chenopodium album L., Amaranthus retroflexus L, Solanum nigrum L., Polygonum lapathifolium L., Cirsium arvense (L.) Scop., Convolvulus arvensis L., and in monoculture — C. album, Ambrosia artemisiifolia L., Xanthium strumarium L., C. arvense. According to the sum of the shares of dominance and subdominance among weed plants, C. arvense prevailed in crop rotation (78%), and X. strumarium prevailed in monoculture (100%). The type of weediness in corn for grain crops in crop rotation differed annually from the type of weediness in monoculture. For the most part, cereal annual weed species prevailed in crop rotation, and dicotyledonous weed species prevailed in monoculture. Under conditions of crop rotation, a lower level of weediness was observed almost every year than in monoculture. Conclusions. The type of weediness in crops of corn for grain in crop rotation differs from the type of weediness in monoculture. for the most part, cereal annual weed species predominate in crop rotation, and dicotyledonous weed species predominate in monoculture.