Waldssimiler Teixeira De Mattos

The objective of this study was to evaluate the use of grazing management strategies (GMS) in rotational stocking to improve the canopy structure in mixed pastures of Marandu palisadegrass (Brachiaria brizantha cv. Marandu) and legume Macrotyloma axillare. Treatments consisted of combinations of defoliation frequencies (pre-grazing heights of 30 and 40 cm) and intensities (post-grazing heights of 15 and 20 cm) in a 2 × 2 factorial arrangement, corresponding to four GMS: 30-15, 30-20, 40-15, and 40-20 cm, allocated to [...] ABSTRACT The objective of this study was to evaluate the use of grazing management strategies (GMS) in rotational stocking to improve the canopy structure in mixed pastures of Marandu palisadegrass (Brachiaria brizantha cv. Marandu) and legume Macrotyloma axillare. Treatments consisted of combinations of defoliation frequencies (pre-grazing heights of 30 and 40 cm) and intensities (post-grazing heights of 15 and 20 cm) in a 2 × 2 factorial arrangement, corresponding to four GMS: 30-15, 30-20, 40-15, and 40-20 cm, allocated to

Multispecies pastures are an alternative to increase sustainability of pasture systems, but evaluating their botanical components is a challenge. The objective of this study was to estimate the presence of botanical components in pastures with different canopy heights through measurement of forage mass, height and frequency. The species were Aruana guineagrass (Megathyrsus maximus cv. Aruana) and three legumes: Macrotyloma axillare cv. Java; Calopogonium mucunoides; and Stylosanthes macrocephala + S. capitata, managed under continuous stocking and variable stocking with sheep. The treatments corresponded to four canopy height targets (CHTs), of 15, 30, 45, and 60 cm, in a randomized block design with four replications, totaling 16 experimental units (paddocks). The herbage mass and botanical and morphological components were measured with monthly cuts in three areas at ground level and separated into Aruana guineagrass, Legumes, Dead Material and Weeds. The canopy height was measured with a sward stick and the botanical components touched by the stick were used to calculate frequency. The herbage mass was greater in taller pastures, while the proportions of Aruana, Legumes and Weeds were similar among CHTs. The frequency of Aruana and Legumes did not differ among CHTs, and Weed frequency was highest in 15 cm pastures. The correlation between the proportion and frequency of Legumes was not significant (P=0.2809). The components’ proportions in the herbage mass, botanical components' height and frequency can be used to estimate their presence in multispecies pastures.

Most gastrointestinal nematodes are in the grazing environment. As an option, the study aimed to evaluate an alternative technique for recovery of infecting larvae in various grass genera: Tyfton 85 (Cynodon dactylon) Capim–Vencedor (Megathyrsus maximus) Capim–Gordura (Melinis minutiflora) Capim–Marandu (Brachiaria brizantha), Setaria (Setaria anceps) Capim-Humidicula (Brachiaria humidicula) and Andropogon (Andropogon gayanus). The collection of samples and procedures were developed at the Institute of Animal Science, Nova Odessa, Brazil. The grasses came from isolated paddocks. Three subsamples were used: 1-control sample (AC1); 2-control frozen sample (ACC2); 3-infested sample (AI). AC1, after the process of larvae recoveries, served as control, the rest was frozen. After de-freezing, it was divided into two samples (ACC2 and AI). In ACC2, no larvae were observed. AI was infested with 1600 ± 30 L3 larvae of trichostrongylids, recovered from sheep manure. The larvae recovery procedures were applied to the samples in the three periods. The overall mean of recovery (±SD) and percentage of success was estimated (SISVAR®) in 1544.63 ± 1.31 larvae, 96.54 ± 17% respectively. There were no differences between grass genera, as well as between weeks, with near recovery numbers (p>0.05). The technique had satisfactory results in a short time.

Diversification in cropping systems can increase production and reduce environmental impacts. Thus, we studied maize production as a function of the cropping system and the nitrogen rates applied as side-dressing. The experimental design involved randomized blocks with four replications in a split-plot scheme. The main plots were maize monoculture; maize intercropped with Congo grass (Urochloa ruziziensis cv. Comum); and maize intercropped with Aruana Guinea grass (Megathyrsus maximus cv. Aruana). The subplots were four nitrogen rates (0; 50; 100 and 150 kg ha⁻¹) applied as side-dressing. The maize and grasses row were fertilized with nitrogen. Maize intercropped with grasses needs an adequate nitrogen supply to be applied as side-dressing.

Combinations between crop intercropping and forage production in a no-tillage system are not well established for environments under low water retention and soil fertility conditions. Our study aimed to evaluate the potential interactions between soybean-grass intercropping with residual nitrogen in a no-tillage system. The experimental design was a randomized block with four replications in a subdivided plot scheme. The main plots in the summer season were: 1) soybean monoculture; 2) soybean - Aruana Guinea grass (Megathyrsus maximus cv. Aruana) intercropping, and 3) soybean - Congo grass (Urochloa ruziziensis cv. Comum) intercropping. The subplots were the nitrogen rates of 0, 50, 100, and 150 kg ha-1, applied as side-dressing in maize and grasses during the autumn-winter season. Here, the results of the summer seasons are shown. To do so, the parameters evaluated were soybean agronomic traits, dry biomass production, and macronutrient concentrations of plants intercropped. The main effects and interactions were studied. Our findings showed that soybean-Aruana Guinea grass intercropping is an alternative to no-tillage system implementation. Moreover, residual nitrogen from the autumn-winter season directly interfered with the dry biomass production of grasses intercropped with soybeans in the summer season. In short, the systems studied seem suitable for implementing a no-tillage system, which aims to neutralize degraded pastures and produce forage for ensilage. Despite the changes in macronutrient concentrations within the intercropping system and residual nitrogen, and among intercropped crops over the years, Congo grass intercropped with soybeans in the summer season showed great capacity for phosphorus, potassium, and magnesium cycling.