The objective was to evaluate the structural, yield and nutritional characteristics of biomass sorghum BRS 716 managed in different row planting spacing and harvest age in a semiarid region of Brazil. Three row spacing (45, 70 and 90 cm; plots) and four maturity at harvest (70, 100, 130 and 160 days; subplots) were evaluated following a randomized block design in a 3 x 4 split plot arrangement, with eight blocks. The useful area was 3 x 15 m. Variation in soil fertility in the area was the blocking factor. There was interaction between row spacing and maturity at harvest (P < 0.05) on plant height (P = 0.01), dry matter yield (DMY; P < 0.01) and proportion of senescent material (P = 0.01). The DMY observed at the age of 160 days and spacing of 90 cm was 41.40% higher than the DMY at the same age and in spacings of 45 and 70 cm (mean of 21.45 t/ha). As the maturity at harvest increased, there was a reduction in the crude protein content (P < 0.01), potential degradability (P < 0.01) and effective degradability (P < 0.01) of dry matter, and the content of non-fiber carbohydrates (P < 0.01), total digestible nutrients (P < 0.01) and the readily soluble fraction (P < 0.01) of the dry matter increased. Considering the yield and nutritional characteristics of biomass sorghum BRS 716 managed in the semiarid region for silage production, the row spacing of 90 cm and the maturity at harvest of 160 days after planting are recommended.

This study aimed to determine and measure the phenolic acids in four varieties of sugarcane (RB 855536, RB 765418, SP 80-1842 and SP 80-1816) as fresh and ensiled, and assess the influence of these acids on in situ degradability of dry matter and neutral detergent fiber. The experimental design was completely randomized in a factorial design. For the fraction of dry matter (DM), varieties RB 855536 and SP 80-1842 had average 17.80% higher compared to others. The SP80-1842 and RB 855536 varieties did not differ (p > 0.05), with an average of DM effective degradability of 33.70%. For silage, the highest levels of p-coumaric acid were found in the variety RB 855536, which was 24.64% higher than the varieties RB 765418 and SP 80-1842 (average 12.75%) and 52.60% of the variety SP 80-1816 (average 8.02%), since for the in natura form, varieties did not differ between each other (p > 0.05), and had an average of 8.86%. Silage variety SP 80-1816 has ferulic acid content 40.82% higher than the other varieties, with an average of 4.63%. The examination of the concentrations of phenolic acids p-coumaric and ferulic are not sufficient to justify the effect of microbial action on the varieties studied in different forms of processing.

Salt stress is a condition that causes physiological changes in several species, the identifying cultivars tolerant to such conditions is essential to high salinity environments. The objective was to evaluate the physiological quality of seeds of chickpea cultivars to salt stress during germination and seedling growth. Two cultivars (‘BRS Cícero’ and ‘BRS Aleppo’) and five osmotic potentials simulated with sodium chloride solutions (0.0; -0.2; -0.4; -0.6 and -0.8 MPa), were evaluated by the test of germination speed index, mean germination time, epicotyl and primary root length, epicotyl and primary root fresh mass, epicotyl and the primary root dry mass of the seeds were evaluated. Significant interactions were found for all variables, indicating that there are cultivars with specific performance for a particular salt condition, and the simulated salt stress conditions negatively affected germination and seedling growth. Osmotic potentials of less than -0.4 MPa are harmful to the germination and growth of chickpea seedlings. The ‘BRS Cícero’ seeds showed a higher salt tolerance than ‘BRS Aleppo’. The cultivar BRS Aleppo has a longer epicotyl length compared to 'BRS Cícero' when subjected to the same conditions of salt stress.

The allocation of the large amount of swine waste from farms is an international concern. An efficient way of managing such waste is its use in farming. It is already known that the incorporation of organic waste into the soil significantly increases the microbial population. Therefore, the objective was to evaluate the impact of the use of swine manure on the soil microbiota in a Eutrophic Oxisol. The experiment was set up in a completely randomized design in a 6 &times; 4 factorial scheme (sixconcentrations of swine manure and four evaluation periods) with four replications. We evaluate the following characteristics: microbial respiration (C-CO2), microbial biomass (&micro;C g-1 soil) and pH.: microbial respiration (C-CO2), microbial biomass (&micro;C g-1 soil) and pH. A significant effect was found in the interaction between concentrations and time of incubation (p &lt; 0.05) of swine manure on microbial activity in the soil. The amount of microbial carbon increased as a function of increased levels of liquid swine manure. No interaction was observed between concentrations and time of incubation for the pH. The evaluation of the isolated factors allowed to observe that the pH decreased as the doses of manure were incremented. Higher and lower pH values were found after 5 and 30 days of incubation. The application of liquid swine manure up to 6000 L ha-1 increases the release of CO2 and carbon in the microbial biomass. The applications of liquid swine manure cause a gradual reduction in soil pH.

Passion fruit (Passiflora edulis) has aroused interest from producers, leading to an intense demand for technical information, especially for obtaining quality seedlings. The objective of this study was to evaluate passion fruit seedlings according to age and morphological characteristics. The experiment was carried out at the seedling nursery of the State University of Montes Claros, Campus Jana&uacute;ba-MG, Brazil, from March to June 2017. The cultivars BRS Gigante Amarelo, BRS Rubi do Cerrado, BRS P&eacute;rola do Cerrado and Redondo Amarelo were evaluated, distributed in randomized blocks with five replications, in a split-plot scheme (4 &times; 4). There was an adjustment of the model (IQM = 6.3857 &minus; 0.3892 NL + 3.3512 SD &minus; 0.2063 SPAD + 0.0730 LA), which proposes a quality parameter of passion fruit seedlings, high level of significance and coefficient of determination, necessary for the reliability and accuracy of the results obtained. Considering the proposed model (IQM), there is no need for destructive analysis, and evaluations can be performed in the nursery itself as soon as a seedling lot reaches the recommended height of 30 cm. The evaluated characteristics contribute significantly to the quality of the seedling, and it is recommended, besides the height measurement, to evaluate the number of leaves, the stem diameter, the leaf area and the SPAD index, because the combination of these parameters will guarantee the necessary quality of the seedlings to be transplanted in the field.