Impact of managing cover crop residues on the floristic composition and species diversity of the weed community of pepper crop (Capsicum annuum L.)

Test of 3 cover crop residues (hairy vetch, oat, canola) used as mulch strip for pepper crop, with 2 different levels of weed management applied to the pepper crop (weed-free, weedy)

Cover crop residue management: residue left on soil surface in no-tillage system; green manure residues at 10 cm of soil depth in minimum tillage; green manure residues at 30 cm of soil depth in conventional tillage.

2-year field experiment was carried out in central Italy to study the effect of cover crop species and their residue management on weed community composition and weed species diversity in a winter cover crop – pepper sequence. Hairy vetch (Vicia villosa Roth.), oat (Avena sativa L.) and canola (Brassica napus L.) were sown in September 2009 and 2010 and grew undisturbed during the winter season until spring when they were suppressed one week before pepper transplanting. Cover crop residues were: (i) green manured at 30 cm depth (conventional tillage, CT), (ii) green manured at 10 cm depth (minimum tillage, MT), and (iii) left on the soil surface as mulch strips covering 50% of the ground area in no-tilled soil (NT). A winter weedy fallow and a bare soil without cover crop in NT, MT and CT were also included as controls.