Env Exp Biol (2013) 11: 189–193

Effect of intercropping with maize on weed diversity in cassava

Abstract

A study to assess the degree of weed species diversity in cassava/maize intercrop and cassava monoculture was conducted at the Teaching and Research Farm of the Federal University of Agriculture Abeokuta in 2010 late wet season and 2011 early wet season using 0.5 × .5 m plots. In total, 33 weed species belonging to 12 families were identified. From these, 10 and 23 were perennials and annuals, respectively, while 15, 16 and two were forbs, grasses and sedges, respectively.Brachiaria jubata,Cyperus rotundus,Dactyloctenium aegyptium, Phyllanthus amarus and Spigelia anthelmia were associated with the two locations in both seasons. Cyperus rotundus was the most frequent species in cassava/maize intercrop in both seasons with 40.08 and 17.82% relative frequency, respectively. However, Brachiaria jubata with 17.82% and Tridax procumbens with 33.33% relative frequency followed the same trend in cassava monoculture plots in the late and wet seasons, respectively. In both seasons, only two weed species: Cyperus rotundus and Phyllanthus amarus consistently had relative density ≥ 5% in the two systems. In cassava/maize intercrop fields, Cyperus rotundus was the most frequent (40.08%) and most dominant species (relative importance value = 29.85%) in cassava/maize intercrop in both seasons, while Brachiaria jubata (relative importance value = 19.7%) and Tridax procumbens (relative importance value = 27.08%) constituted the dominant species in cassava monoculture field during the late 2010 and early 2011 seasons, respectively. The future incidence of Cyperus rotundus may probably be brought under control with shallow tillage at frequent intervals.