FORAGE GRASS COVER CROPS AND THEIR EFFECTS ON CORN DEVELOPMENT AND WEED INFESTATION

Abstract

This work aimed to evaluate the effect of forage grass cover crops on corn development and weed infestation suppression. The treatments consisted of three cover crops, brachiaria, pearl millet and an interspecific sorghum hybrid (BRS 800), submitted or not to one cut 60 days after planting, and a check plot (fallow land). The experiment was conducted at Embrapa Corn and Sorghum Center, Sete Lagoas-MG, in the period from March 2006 to February 2007. Brachiaria reduced the initial corn stand, plant and ear height, but there was no significant difference in the final stand. Corn stalk diameter was smaller using pearl millet as cover crop. No significant differences were observed among treatments or between cover crops and control for the other parameters. Also, no significant effect of cut was observed on corn agronomic characteristics and grain yield. For the three evaluated cover crop species, weed infestation was considerably reduced when compared to the check plot (fallow land). Cut did not show any significant effect on weed suppression. Brachiaria was superior than sorghum and pearl millet regarding mulch volume and weed infestation reducing, indicating a possible correlation between the two variables.

Keywords

• mulching
• Brachiaria brizantha
• Pennisetum glaucum
• Sorghum bicolor x Sorghum sudanens
• Zea mays L