Upland rice yield as affected by previous summer crop rotation (soybean or upland rice) and glyphosate management on cover crops

The appropriate chemical management of cover crops in no-tillage aims to obtain greater benefits with its employment in agricultural systems. The objective of this study was to assess upland rice yield as affected by the previous summer crop, species and desiccation timing of cover crops by glyphosate. Sown cover crops were sown (November 2007), followed by rice in half of the experimental area and soybean in the other half (November 2008). After the harvesting of these crops, the same cover crops were sown again (March 2009) and followed by upland rice in the total area (November 2009). The experiment consisted of the combination of five cover crops (fallow, Panicum maximum, Brachiaria ruziziensis, B. brizantha and Pennisetum glaucum), four desiccation timings (30, 20, 10 and 0 days before rice sowing), and two antecedents of the summer crop (rice or soybean) under no-tillage system (NTS), plus two control treatments at conventional tillage system (CTS). Cover crops significantly affect rice grain yield and its components. There is a significant tendency to highest yield when cover crop desiccation is conducted farther from the rice sowing date (from 2,577.1 kg ha-1 - desiccation at rice sowing to 3,115.30 kg ha-1 - desiccation 30 days before rice sowing). Soybean as an antecedent of summer crop allows better upland rice yield (3,754 kg ha-1) than rice as an antecedent of summer crop (2,635 kg ha-1); fallow/soybean/fallow (4,507 kg ha-1) and millet/soybean/millet (4,765 kg ha-1) rotation at no-tillage system, and incorporated fallow /soybean/ incorporated fallow (4,427 kg ha-1) at conventional tillage system allow the highest rice yield; upland rice yield is similar at no-till (3,194 kg ha-1) and till system (2,878 kg ha-1).

Influence of air temperature on proteinase activity and beverage quality in Coffea arabica

Fruits were collected from trees of Coffea arabica cv. Obatã grown at Mococa and Adamantina in São Paulo State, Brazil, which are regions with marked differences in air temperature that produce coffee with distinct qualities. Mococa is a cooler location that produces high-quality coffee, whereas coffee from Adamantina is of lower quality. The amino acid and protein contents, amino acid profile, and proteinase activity and type in endosperm protein extracts were analysed. Proteinase genes were identified, and their expression was assayed. All results indicate that temperature plays a role in controlling proteinase activity in coffee endosperm. Proteinase activity was higher in the endosperm of immature fruits from Adamantina, which was correlated with higher amino acid content, changes in the amino acid profile, and increased gene expression. Cysteine proteinases were the main class of proteinases in the protein extracts. These data suggest that temperature plays an important role in coffee quality by altering nitrogen compound composition.

Food and the circadian activity of the hypothalamic-pituitary-adrenal axis

Temporal organization is an important feature of biological systems and its main function is to facilitate adaptation of the organism to the environment. The daily variation of biological variables arises from an internal time-keeping system. The major action of the environment is to synchronize the internal clock to a period of exactly 24 h. The light-dark cycle, food ingestion, barometric pressure, acoustic stimuli, scents and social cues have been mentioned as synchronizers or" zeitgebers". The circadian rhythmicity of plasma corticosteroids has been well characterized in man and in rats and evidence has been accumulated showing daily rhythmicity at every level of the hypothalamic-pituitary-adrenal (HPA) axis. Studies of restricted feeding in rats are of considerable importance because they reveal feeding as a major synchronizer of rhythms in HPA axis activity. The daily variation of the HPA axis stress response appears to be closely related to food intake as well as to basal activity. In humans, the association of feeding and HPA axis activity has been studied under physiological and pathological conditions such as anorexia nervosa, bulimia, malnutrition, obesity, diabetes mellitus and Cushing's syndrome. Complex neuroanatomical pathways and neurochemical circuitry are involved in feeding-associated HPA axis modulation. In the present review we focus on the interaction among HPA axis rhythmicity, food ingestion, and different nutritional and endocrine states

Corn germ with pericarp in relation to whole corn: nutrient contents, food and protein efficiency, and protein digestibility-corrected amino acid score

The germ fraction with pericarp (bran) is generated in the industrial processing of corn kernel, and it is used for oil extraction and animal feed. This study evaluated the nutritional and protein quality of this fraction in relation to whole corn. The proximate composition, mineral contents, and amino acid profile of the germ fraction with pericarp and of whole corn were determined. A 4-week experiment was conducted using 36 weanling male Wistar rats, and three 10%-protein diets (reference, germ with 15% lipids and casein with 15% lipids), two 6%-protein diets (whole corn and casein), and a protein-free diet were prepared. The germ showed higher contents of proteins, lipids, dietary fiber (27.8 g.100 g-1), ash, minerals (Fe and Zn- approximately 5 mg.100 g-1), and lysine (57.2 mg.g-1 protein) than those of corn. The germ presented good quality protein (Relative Protein Efficiency Ratio-RPER = 80%; Protein Digestibility-Corrected Amino Acid Score-PDCAAS = 86%), higher than that of corn (RPER = 49%; PDCAAS = 60%). The corn germ fraction with pericarp is rich in dietary fiber, and it is a source of good quality protein as well as of iron and zinc, and its use as nutritive raw material is indicated in food products for human consumption.

5th Food Safety and Security Symposium: food and health

Abstract The 5º Simpósio de Segurança Alimentar (5th Food Safety and Security Symposium) was held in May, 2015, in Bento Gonçalves, RS, Brazil with the objective of discussing the interrelation between food and health, in various perspectives. This paper reviews the state of the art regarding all the issues discussed during the Symposium, connecting them with the lectures presented at the conference. As final remarks, it was perceived that the interrelation between food and health is growing stronger and cannot be discussed without involving the different areas involved.

BK polyomavirus in Kidney transplant recipients: screening, monitoring and clinical management

BK polyomavirus (BKPyV) is a causal agent of nephropathy, ureteral stenosis and hemorrhagic cystitis in kidney transplant recipients, and is considered an important emerging disease in transplantation. Regular screening for BKPyV reactivation mainly during the first 2 years posttransplant, with subsequent pre-emptive reduction of immunosuppression is considered the best option to avoid disease progression, since successful clearance or reduction of viremia is achieved in the vast majority of patients within 6 months. The use of drugs with antiviral properties for patients with persistent viremia has been attempted despite unclear benefits. Clinical manifestations of BKPyV nephropathy, current strategies for diagnosis and monitoring of BKPyV infection, management of immunosuppressive regimen after detection of BKPyV reactivation and the use of antiviral drugs are discussed in this review.