Riparian areas as invasion corridors of Xanthium strumarium in Serbia

Abstract

Xanthium strumarium L., also known as common cocklebur, is a potentially invasive weed species in Serbia. It is one of the most competitive weeds, strongly affecting the yield of some crops, such as maize, soybean, sunflower, sugar beet, etc. Since watercourses act as important transportation routes for the long-distance dispersal of weeds and the fruit of X. strumarium is easily dispersed by water, our aim was to analyse the degree of X. strumarium invasion in riparian areas of Serbia and examine the role of rivers and canals as its potential invasion corridors. The field research was carried out during the summer months of 2013,2014, and 2015, along the course of 35 rivers and five major canals of the Danube- Tisa-Danube Hydrosystem (HSDTD) in Serbia. Fieldwork was conducted along 100 m long transects of 500 m long river stretches (chosen following the RHS methodology), where the invasive alien weed species presence and abundance were recorded. Over the period of three years, the presence of X. strumarium was recorded along the course of 33 rivers (94.25%), while it was documented along 66.85% of the total number of river stretches. However, along the canals, it was recorded in only 12% of the localities. The data on the distribution ofX. strumarium expand the existing knowledge on the distribution of this economically harmful weed species in our country, while at the same time highlighting riparian areas of rivers as potentially important corridors of its spread.

Xanthium strumarium L. u narodu poznat kao obična ili zelena boca, je potencijalno invazivna korovska vrsta na području Srbije. Jedna je od najkompetitivnijih korovskih vrsta, koja jako utiče na prinos nekih kultura, kao što su kukuruz, soja, suncokret, repa, itd. Imajući u vidu činjenicu da vodotokovi predstavljaju značajne transportne puteve za disperziju korovskih vrsta na veće razdaljine, naš cilj je bio da analiziramo stepen invazije X. strumarium u riparijalnim područjima Srbije i ispitamo kakva je uloga reka i kanala kao njegovih potencijalnih koridora invazije. Terenska istraživanja obavljena su u periodu letnjih meseci 2013, 2014. i 2015. godine, duž toka 35 reka i pet glavnih kanala hidrosistema Dunav-Tisa-Dunav u Srbiji. Istraživanja su vršena na 100m dugim transektima u okviru 500 m dugih deonica rečnog toka (odabranih u skladu sa RHS metodologijom), gde su beleženi prisustvo i pokrovnost stranih invazivnih biljnih vrsta. Tokom trogodišnjeg perioda istraživanja, prisustvo X. strumarium zabeleženo je duž toka 33 reke (94,25%), a duž 66,85% od ukupnog broja rečnih deonica. Međutim, duž toka kanala, ova potencijalno invazivna vrsta registrovana je na samo 12% lokaliteta. Podaci o rasprostranjenju vrste X. strumarium proširuju postojeće znanje o rasprostranjenju ove ekonomski značajne korovske vrste u našoj zemlji, dok u isto vreme ističu riparijalne oblasti reka kao potencijalno značajne koridore njenog širenja.