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The productive, morphological and chemical composition of Sudangrass ‘BRS Estribo’ submitted to different heights of management was evaluated. The design was in randomized blocks with four replicates in a 3x2 factorial scheme, with three pre-defoliation heights (40, 55 and 70 cm) and two post-defoliation heights (20 and 10 cm). There was no significance between post-defoliation heights for accumulated forage production (AFP), percentages of leaf blades (%F) and of stem and sheath (%S). The AFP at 70 cm pre-defoliation height (10,071.1 kg ha-1) was higher than at 40 cm height (7,471.3 kg ha-1) and did not differ from defoliation at 55 cm (8,562.3 kg ha-1). Predefoliation at 40 cm showed a higher %F (67.67%) than at the heights of 55 cm (61.74%) and 70 cm (55.15%), which differed from each other. The %S was higher for pre-defoliation at 70 cm (35.57%) than at the heights of 55 (32.08%) and 40 cm (27.75%), which also differed from each other. The different handling heights did not change the contents of dry matter, insoluble fiber in neutral detergent, insoluble fiber in acid detergent and ash, which presented averages of 15.87; 60.34; 28.53; and 10.48%, respectively. However, there was a significant interaction between pre-and post-defoliation heights for crude protein (CP) contents, which the management heights at 40 x 20 cm and 70 x 10 cm presented, respectively, the highest (18.78%) and lowest (12.22%) CP contents of the study. Pre-defoliation heights of 55 cm with 10 or 20 cm of residual height should be used to improve the botanical composition and crude protein content of Sudangrass BRS Estribo forage.

The productive, morphological and chemical composition of Sudangrass ‘BRS Estribo’ submitted to different heights of management was evaluated. The design was in randomized blocks with four replicates in a 3x2 factorial scheme, with three pre-defoliation heights (40, 55 and 70 cm) and two post-defoliation heights (20 and 10 cm). There was no significance between post-defoliation heights for accumulated forage production (AFP), percentages of leaf blades (%F) and of stem and sheath (%S). The AFP at 70 cm pre-defoliation height (10,071.1 kg ha-1) was higher than at 40 cm height (7,471.3 kg ha-1) and did not differ from defoliation at 55 cm (8,562.3 kg ha-1). Predefoliation at 40 cm showed a higher %F (67.67%) than at the heights of 55 cm (61.74%) and 70 cm (55.15%), which differed from each other. The %S was higher for pre-defoliation at 70 cm (35.57%) than at the heights of 55 (32.08%) and 40 cm (27.75%), which also differed from each other. The different handling heights did not change the contents of dry matter, insoluble fiber in neutral detergent, insoluble fiber in acid detergent and ash, which presented averages of 15.87; 60.34; 28.53; and 10.48%, respectively. However, there was a significant interaction between pre-and post-defoliation heights for crude protein (CP) contents, which the management heights at 40 x 20 cm and 70 x 10 cm presented, respectively, the highest (18.78%) and lowest (12.22%) CP contents of the study. Pre-defoliation heights of 55 cm with 10 or 20 cm of residual height should be used to improve the botanical composition and crude protein content of Sudangrass BRS Estribo forage.

In a recent paper (Chian et al., 2016) it was shown that magnetic reconnection at the interface region between two magnetic flux ropes is responsible for the genesis of interplanetary intermittent turbulence. The normalized third-order moment (skewness) and the normalized fourth-order moment (kurtosis) display a quadratic relation with a parabolic shape that is commonly observed in observational data from turbulence in fluids and plasmas, and is linked to non-Gaussian fluctuations due to coherent structures. In this paper we perform a detailed study of the relation between the skewness and the kurtosis of the modulus of the magnetic field |B| during a triple interplanetary magnetic flux rope event. In addition, we investigate the skewness–kurtosis relation of two-point differences of |B| for the same event. The parabolic relation displays scale dependence and is found to be enhanced during magnetic reconnection, rendering support for the generation of non-Gaussian coherent structures via rope–rope magnetic reconnection. Our results also indicate that a direct coupling between the scales of magnetic flux ropes and the scales within the inertial subrange occurs in the solar wind.

BackgroundThe Arc of Fire across southern Amazonia seasonally attracts worldwide attention as forests are cut and burned for agricultural expansion. These forests contain numerous wild relatives of native South American crops, such as peach palm.Methodology/principal findingsOur prospecting expeditions examined critical areas for wild peach palm in the Arc of Fire in Mato Grosso, Pará, Maranhão and Tocantins, as well as areas not previously examined in Amazonas and Amapá states. Recent digitization of the RADAM Brasil project permitted comparison among RADAM's parataxonomists' observations, previous botanical collections and our prospecting. Mapping on soils and vegetation types enabled us to hypothesize a set of ecological preferences. Wild peach palm is best adapted to Ultisols (Acrisols) in open forests across the Arc of Fire and westward into the more humid western Amazonia. Populations are generally small (fewer than 10 plants) on slopes above watercourses. In northern Mato Grosso and southern Pará soybean fields and pastures now occupy numerous areas where RADAM identified wild peach palm. The controversial BR-163 Highway is already eroding wild peach palm as deforestation expands.Conclusions/significanceMany of these populations are now isolated by increasing forest fragmentation, which will lead to decreased reproduction via inbreeding depression and eventual extinction even without complete deforestation. Federal conservation areas are less numerous in the Arc of Fire than in other parts of Brazilian Amazonia, although there are indigenous lands; these conservation areas contain viable populations of wild peach palm and require better protection than they are currently receiving. Ex situ conservation of these populations is not viable given the relative lack of importance of domesticated peach palm and the difficulty of maintaining even economically interesting genetic resources.