Phenological characteristics of wild cucumber (Echinocystis lobata (Michx.) Torr. et A. Gray.) in Nemunas coastal populations

Abstract

Wild cucumber – herbaceous, annual plant, usually growing in coastal habitats like banks of the rivers, around the lakes and other over moistured sites also wastelands. This plant is native in North America. It can be cultivated as an ornamental plant for its flowers and spiny, ornamental fruits. Wild cucumber (Echinocystis lobata) in Lithuania and in other parts of Europe is recognized as invasive species, and considered to be one of the most dangerous according to intensity of the spread along continent part with the temperate climate. The objective of present study was to perform comparative phenology of the wild cucumber (Echinocystis lobata) populations and to collect plant material. Population detection and sampling took place in April–September, 2015. For observations of the plant development during vegetation season 4 out of 25 riparian populations of the Nemunas basin were selected – below Kaunas hydroelectric power station (Kaunas, Panemunė district), before tributary Nevėžis flows into the Nemunas (Kaunas, Lampėdžiai district), and sites upper and lower than Jurbarkas city. Morphometric analyses were monthly performed at selected sites. Our analysis revealed that main and lateral shoot length (cm), averaged per plant has expanded from 62 cm in June to 1152 cm in August. The average length of the main stem (cm) in June–August has augment from 62 cm to 471 cm. The avarage number of plant tendrils augment from 5 to 69 during growing season. In the course of the growing season plant stem diameter has increased from 3.9 mm to 6.2 mm. Within vegetation average number of the leaves (longer than 1 cm) per plant increased from 6 to 71 during the growing season. The length of the longest plant leaflet ranged from 5.8 cm to 12.5 cm. The biggest width of the leaflet (mean per plant) ranged from 6.6 cm to 16.7 cm.[...]Biologijos katedraGamtos mokslų fakultetasVytauto Didžiojo universiteta