Abstract

Dimitrios Bilalis, Anestis Karkanis and Aspasia Efthimiadou

Field experiments were conducted to determine the effects of vetch (Vicia sativa c.v lexander) and red clover (Trifolium pratense c.v Nemaro) on weed flora. The design of the experiment was randomized complete block with 4 replicates and 3 treatments (a: vetch crop, b: red clover crop and c: control (fallow)). Both legume crops suppressed weed biomass. The lowest number and dry weight of weeds was found in vetch plots. The highest height of weeds was found in control plots. Moreover, the highest multiplied dominance ratio (MDR) of weeds was found in the control plot. Vetch was the most competitive legume crop. The number of shoots per plant and dry weight were considered suitable attributes for weed suppression, although competitiveness is a relative rather an absolute characteristic. In addition, red clover is considered a poor competitor because of lack of seedling vigour and slow establishment. Statistically significant negative correlation between the fraction of photosynthetically active radiation (PAR) intercepted by the canopy, weed density and weed biomass was observe d. The MDR of weeds (Lamium aplexicaule, Papaver rhoeas, Sinapis arvensis, Chamomilla recutita and Phalaris minor) had a good correlation with dry weight of weeds. Analysis of MDR demonstrated that L. aplexicaule and C .recutita are poor competitors because of small leaves and low height. Final, S. arvensis and P. minor were the most competitive weeds.