Germination of Parthenocissus quinquefolia (L.) Planch. s.str. (Vitaceae) as a predictor of invasive status this species in the flora of Ukraine
Kalista M.S., Kovalenko O.A. 
Department of Botany, National Museum of Natural History of NAS of Ukraine, Bohdana Khmelnytskoho 15, 01607 Кyiv, Ukraine

Проростання Parthenocissus quinquefolia (L.) Planch. s.str. (Vitaceae) як показник інвазійного статусу виду у флорі України
Каліста М.С., Коваленко О.А.
Відділ ботаніки, Національний науково-природничий музей НАН України, вул. Б. Хмельницького, 15, 01607, Київ, Україна
e-mail: crambe@ukr.net

Annotation. The question about possibility of invasion of Parthenocissus quinquefolia (L.) Planch. s.str. on the territory Ukraine is still open. We provide analysis of biology of germination of P. quinquefolia as a predictor of invasive status this species in the flora of Ukraine. Our results show that the most critical ecological factors are humidity and lighting. 

Genus Parthenocissus Planch. includes 12 species native to the Himalayas, Eastern Asia and North America (Nie et al., 2010). Some of these species are invasive in different regions of the Earth. In Ukraine 3 species are noticed, but only Parthenocissus vitacea (Knerr) Hitchc (= P. inserta (A. Kern.) Fritsch) can escape from the places of cultivation (Mosyakin, Fedoronchuk, 1999). For a long time, Ukrainian botanists did not recognize P. vitacea and P. quinquefolia (L.) Planch. due to close morphological similarity of this species. In many floristic works exactly P. quinquefolia is listed as invasive species. 
Our results show that the most critical ecological factor is humidity. The highest rank of germination was 73 % in condition of sufficient moisture, 37 % in condition of excessive moisture and only 3 % in condition insufficient moisture. Among variants with different reaction of medium the most successful germination was in Petri dishes with pH 7 (73 %) and pH 9 (44 %). Significant factor for seedlings formation of P. quinquefolia is lighting, because in full-dark, dark in semi-dark conditions the level of germination was 0 %, 2 % and 24 % respectively. The gemination of P. quinquefolia demonstrate reverse correlation with levels of salinity. The influence of temperature on germination is not significant, but most optimal regime was +25 oC. 
Further study of biology P. quinquefolia allow to clarify the difference in level of naturalization of this species and close species P. vitacea and make estimation of the possibility of transformation of the introduced species into invasive.