Brachiaria ruziziensis and herbicide on the yield of upland rice

Abstract

-The correct management of cover crops in no-tillage aims to obtain greater benefits with its introduction in agricultural systems. The use of forage species such as Brachiaria, due to the large amount of biomass and for persisting longer on the ground, has become a good option. In this sense, an important point is the time interval between the cover desiccation with glyphosate and planting of rice in order to obtain higher operating income in the sowing, greater availability of nutrients, greater presence of straw on the soil surface, and lower release of possible allelopathic substances. The objective of this study was to assess the effect of the management of B. ruziziensis, with or without herbicide, preceding the crop planting, in the yield components and yield of rice. The trial was conducted in greenhouse conditions and consisted of three types of management of B. ruziziensis before sowing rice. B. ruziziensis showed linear growth and the presence of large amounts of its dry matter biomass on the soil surface was detrimental to rice yield; B. ruziziensis management close to planting caused a significant reduction in rice yield; the management of B. ruziziensis with herbicides should be conducted with more than 20 days before planting rice; the management of B. ruziziensis for the removal of its leaves with or without herbicide should be carried out with 10 or more days before planting rice, and the correct management of B. ruziziensis at the right time allowed for significant increases in the rice yield.Keywords: soil management, straw, cover crops, no tillage system, glyphosate. Palavras-chave: manejo do solo, palhada, plantas de cobertura, sistema de plantio direto, glifosato. RESUMO -O manejo das plantas de cobertura visa obter maiores benefícios com a sua introdução nos sistemas agrícolas. O uso de espécies forrageiras como as do gênero

Intercropping Time of Corn and Palisadegrass or Guineagrass Affecting Grain Yield and Forage Production

“…Forage DM production up to 4000 kg ha −1 could be considered good. Usually at this time of year (July), the availability of forage in areas with dry winters is limited (Crusciol et al, 2010; Pacheco et al, 2011; Nascente et al, 2012). Borghi and Crusciol (2007) reported that in regions with dry winters, sowing forage would be impossible to provide fodder during autumn, winter, and part of spring after corn grain harvest.…”

“…This is because corn is traditionally grown by farmers and has a high number of cultivars adapted to different ecological regions and exhibits excellent adaptation in intercropping systems (Silva et al, 2004; Freitas et al, 2008; Sulc and Tracy, 2007; Tracy and Zhang, 2008). Besides, the use of perennial forages such as palisadegrass or guineagrass is important because these plants have deep root systems, higher drought tolerance compared with cash crops, and higher dry matter (DM) production, ranging from 10 to 20 Mg ha −1 (Kluthcouski et al, 2003; Barducci et al, 2009; Crusciol et al, 2012; Nascente and Crusciol, 2012; Nascente et al, 2012).…”

Upland rice yield as affected by Brachiaria coverage management

“…Matallo et al (2009) add that due to systemic nature of glyphosate its effect on plants is slow and coverage takes a few days to die completely. When using the system to apply this herbicide on cover crops close to sowing day, these plants are not yet completely dried and may impair the operations of sowing, and the initial crop development (Grisso et al, 2002;Nascente et al, 2012b;2013c).…”

“…Once the amounts of biomass produced by cash crops are not enough for an adequate ground cover, it is necessary to introduce cover crops to produce the required volume of biomass in the off-season Nascente et al, 2013c). Then, soil will remain covered as long as possible until the following summer crop (Nascente et al, 2012b). Forage species such as Brachiaria genus is being used as a cover crop because it produces large amounts of biomass and persists longer on the soil surface, especially in times of shortage of rain (Valle & Pagliarini, 2009;Crusciol et al, 2013;Freitas et al, 2013).…”

Viabilidade agroeconômica de rotação de culturas e manejo do solo em áreas irrigadas por aspersão

“…Com relação ao manejo do solo, a desestruturação do solo, a compactação e a redução nos teores de matéria orgânica são consideradas as principais indutoras da degradação dos solos agrícolas, sendo estas causadas principalmente pelo preparo convencional do solo (KLUTHCOUSKI et al, 2000). O sistema plantio direto (SPD) é considerado um sistema sustentável em razão da manutenção dos restos vegetais na superfície do solo, da maior conservação da umidade, do aumento dos teores de matéria orgânica e dos menores riscos de erosão (LOSS et al, 2012;NASCENTE et al, 2012a;MAUAD et al, 2013;NASCENTE et al, 2013b). O Brasil tem cerca de 50 milhões de hectares cultivados com culturas anuais e cerca de metade destes está sob SPD (NASCENTE; CRUSCIOL; COBUCCI, 2013c).…”