Improving Soil Fertility and Crop Yield in a Tropical Region with Palisadegrass Cover Crops

Abstract

In tropical regions with dry winters, low plant biomass accumulation during the period between spring–summer crop cultivations can negatively impact soil resources and make the no‐till (NT) system unsustainable. Incorporating palisadegrass [Urochloa brizantha (Hochst. Ex A. Rich.) R.D. Webster] [syn. Brachiaria brizantha (Hochst. Ex A. Rich) Stapf] in traditional grain production areas could improve soil quality for subsequent crops and lead to positive effects on grain yield. The objective of this study was to evaluate the effects of growing palisadegrass on soil fertility, plant nutrition, and grain yield of subsequent cash crops in a tropical region. The experiment was performed in southeastern Brazil in plots that were grown for two consecutive growing seasons (2002–2003 and 2003–2004) with either monocropped corn (Zea mays L.) or corn intercropped with palisadegrass. An initial evaluation of soil fertility was performed in November 2004 when the land was either fallow (following monocropped corn) or covered by palisadegrass (intercropped areas). After the preceding treatments, the following crops were cultivated: soybean [Glycine max (L.) Merr.] during the 2004–2005 and 2005–2006 spring–summer, white oat (Avena sativa L.) during the 2005 and 2006 fall–winter, and corn during the 2006–2007 spring–summer. Intercropping palisadegrass with corn increased the soil fertility compared to monocropped corn. Soybean, white oat, and corn all had higher leaf macronutrient concentrations and grain yields in previously intercropped areas than in monocropped areas. Therefore, the periodic, short‐term incorporation of a perennial forage grass, such as palisadegrass, as a cover crop is recommended to increase grain production and to improve the soil fertility of grain‐production areas.

Chemical evidence for the effect of Urochloa ruziziensis on glyphosate‐resistant soybeans

“…Brachiaria ruziziensis ) is a plant that can grow in various soils, from sandy to clayey, and it develops best in well‐drained soils with good fertility. The biomass production of these plants results in high levels of P and K present in soil . U. ruziziensis has faster decomposition and lower half‐life values than other plants and this in turn leads to nutrient recycling and higher maize yields …”

Contribution of roots and shoots of Brachiaria species to soybean performance in succession

“…Brachiaria) species for their use either as cover crops or for fodder production in crop-livestock integration (CLI) (Balbinot Junior et al, 2009;Crusciol et al, 2015). The species U. ruzizizensis and U. brizantha show great capacity for dry matter production, even in low-fertility environments, and provide adequate soil cover (Timossi et al, 2007;Franchini et al, 2014a), high-nutrient cycling (Pacheco et al, 2011;Merlin et al, 2013), high-weed suppression capacity (Pacheco et Pesq.…”

“…Urochloa roots improve the soil physical quality (Andrade et al, 2009;Crusciol et al, 2015), which may result in the increased infiltration and water retention, as well as in the improvement of the oxygen flow in the soil, and in the reduced soil resistance to root penetration. In addition, the root growth of U. ruziziensis increases the P availability to plants (Merlin et al, 2013), and straw reduces the rate of water evaporation from the soil, decreasing the peaks of heating (Dalmago et al, 2010) and weed infestation (Balbinot Jr. et al, 2007), reducing soil erosion (Schick et al, 2000), and releasing nutrients to crops in succession (Calonego et al, 2012).…”

Corn yield, forage production and quality affected by methods of intercropping corn and Panicum maximum

“…However, most farms in South America have cultivated the fields with annual crops for years, then, moved on to intercropping between maize and tropical grass . After the harvest of the annual crop, fields can be grazed by the livestock (Crusciol et al, 2015).…”