The paper analyzes alien component of the cenoflora of wheat crops surveyed in 2019–2022 in the Penza region. 42 adventive species were revealed, which is 25.9% of the total number of weeds in wheat fields. The leading families in terms of the species number are Asteraceae (10 species), Brassicaceae (9), Poaceae (7). As far as the immigration ways are concerned, xenophytes predominate (40), according to naturalization degree epecophytes prevail (38). More than half of the introduced species are archaeophytes (23) of Mediterranean and Iranian-Turanian origin. Plants of North American origin make up 47 % of the neophytes. The spectrum of life forms of adventive plants is dominated by herbaceous annual and biennial plants (88.1 %), indicative of the specific environments of this agrocenosis type. Tripleurospermum inodorum (L.) Sch. Bip. is the most widespread alien species in wheat crops of the Penza region. Investigation of wheat fields have resulted in registering of two quarantine objects of North American origin, namely Cuscuta campestris Yunck. and Ambrosia trifida L.

E.A. Sukholozova