Intercropping of soybean cultivars with Urochloa

Abstract

The integrated crop-livestock system is a key strategy for both grain and livestock production. The cultivation of grass species in between two soybean cropping seasons has been an important component of this system, in Brazil. Thus, this study aimed to evaluate the yield of glyphosate-resistant soybean cultivars intercropped with Urochloa species, under different forage management systems. A total of six experiments, consisting of three soybean cultivars (BRS 295 RR, BRS 316 RR, and BRS 294 RR) and two grass species (Urochloa ruziziensis and Urochloa brizantha), were established. For each experiment, four treatments (soybean only; grass only; soybean intercropped with a grass species, with the application of glyphosate to decrease the growth of grass; and soybean intercropped with a grass species, without growth suppression) were evaluated in a completely randomized experimental design, with four replications. For each experiment, only one soybean cultivar and one grass species were used. The grasses were sown in the soybean inter-rows at 27 days after sowing (DAS), while the glyphosate application to the treatment with grass suppression was performed at 84 DAS for the soybean or 57 DAS for the grasses. The yields of the three soybean cultivars were not significantly affected by either grass species, even though the shoot dry-matter yields for both of the intercropped grass species were high, though lower than the values obtained without the interference imposed by soybean.

Establishment of perennial forages intercropped with soybean for integrated crop-livestock systems

“…The average insertion height of the first pods ranged from 12.5 to 14.5 cm; however, no differences were observed between cultivation modalities, which is in alignment with Franchini et al (2014) and Crusciol et al (2014), but differs from Silva et al (2004) and Crusciol et al (2012). The average height of plants and of the insertion of the first pods are characteristics that vary between soybean genotypes and present some plasticity in relation to environmental changes (Crusciol et al, 2012;Franchini et al, 2014). Soybean cultivars larger in size and with a higher pod insertion height may be more competitive for light and, therefore, less susceptible to competition with forages and to the grain depreciation caused by impurity, at harvest time.…”

“…Studies conducted by Crusciol et al (2012Crusciol et al ( , 2014 and Franchini et al (2014) showed changes in this variable between years or among genotypes. The average insertion height of the first pods ranged from 12.5 to 14.5 cm; however, no differences were observed between cultivation modalities, which is in alignment with Franchini et al (2014) and Crusciol et al (2014), but differs from Silva et al (2004) and Crusciol et al (2012). The average height of plants and of the insertion of the first pods are characteristics that vary between soybean genotypes and present some plasticity in relation to environmental changes (Crusciol et al, 2012;Franchini et al, 2014).…”

“…Numerical but not significant differences were observed for this variable, similarly to what was reported in other studies with soybean intercropped with forages of the genus Urochloa spp. (Pereira et al, 2011;Mariani et al, 2012;Saraiva et al, 2013;Franchini et al, 2014).…”

“…Although several studies on intercropping focus on the possibility of competition between forages and soybean, there are no reports on changes in the grain yield components of the oilseed when intercropped with grasses (Mariani et al, 2012;Saraiva et al, 2013;Crusciol et al, 2014;Franchini et al, 2014). Significant differences, however, were found by Crusciol et al (2012) and Saraiva et al (2014), who observed reduction in the number of pods per plant and of grains per pod in the soybean + U. brizantha intercropping.…”

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

“…The Urochloa species were sown in November 2014, in consortium with soybean, using 7 kg ha -1 of pure and viable seed, which were placed in lines allocated between the soybean rows, according to Franchini et al (2014b). After the soybean harvest, in February 2015, the grasses remained as cover crops in the plots, in the autumn-winter period.…”