Fitness assessment of weedy sunflower populations (Helianthus annuus L.)

Abstract

Three weedy sunflower (Helianthus annuus L.) populations (WS-P1 and WS-P2 - originated from sites where herbicide ALS inhibitors used many years; WS-P3- was obtained from a site where herbicides was never used) were studied for ecological fitness assessment. Vegetative parameters (plant height, fresh weight, leaf area), relative chlorophyll content, fecundity and percentage of germination, length and weight of seedlings in filed/control conditions were recorded during two years. The most frequently WS-P1 and WS-P2 populations were of better ecological fitness than the WS-P3 population. Based on the results it was found that populations of WS which originated from sites where herbicides permanent used are with better ecological fitness in compare with population which originated from a site where herbicides was never used it was connect with genetic diversity and polymorphism which could promote the invasiveness of these weedy sunflower populations in landscape.

Tri populacije korovskog suncokreta (Helianthus annuus L.) (KS-P1 i KS-P2 - potiču sa površina gde je duži niz godina bilo primene herbicida ALS inhibitora; KS-P3- potiče sa površine gde nikada nije bilo primene herbicida) su ispitivane u cilju procene njihovog fitnesa. Za procenu fitnesa u poljskim uslovima proučavani su vegetativni parametri (visina biljaka, sveža masa, lisna površina), relativni sadržaj hlorofila, prinos i parametri prinosa (broj glavica po biljci i prečnik glavice). U kontrolisanim uslovima ispitivana je klijavost semena, dužina i masa klijanaca. Na osnovu dobijenih rezultata zaključeno je da populacije KS koje potiču sa površina gde su primenjivani herbicidi su sa boljim vegetativnim i generativnim potencijalom, a što se može dovesti u vezu sa izraženijim genetičkim polimorfizmom koji im omogućava veću i uspešniju invazivnost.