Exploration on coloured plastic film mulch for controlling weeds in tomato and maize fields.
The weed controlling effects of mulching by black, silver-lustred, red, yellow and green plastic with thicknesses of 0.019, 0.019, 0.017, 0.017 and 0.014 mm, resp., were evaluated and compared to mulching with common transparent thin plastic film in field trials conducted in tomatoes and maize in Gansu. The most problematic annual weeds were Chenopodium album, C. glaucum, Polygonum aviculare, Portulaca oleracea, Echinochloa crus-galli and Setaria viridis. Black film resulted in 100% control of all weeds in tomatoes and maize, whereas silver-lustred thin film resulted in 100 and 92% control of graminaceous weeds and 90 and 67.2% control of broadleaved weeds in tomatoes and maize, resp. All other coloured films resulted in 50% control of weeds in both tomato and maize. Black and silver-lustred film mulch resulted in increased tomato yields of 27.71 and 15.1%, and maize yields of 27.5 and 24.2%, resp., when compared to common transparent thin film.