Carbon in humic fractions of organic matter in soil treated with organic composts under mango cultivation.

Soil organic matter (SOM) plays a key role in maintaining the productivity of tropical soils, providing energy and substrate for the biological activity and modifying the physical and chemical characteristics that ensure the maintenance of soil quality and the sustainability of ecosystems. This study assessed the medium-term effect (six years) of the application of five organic composts, produced by combining different agro-industrial residues, on accumulation and chemical characteristics of soil organic matter. Treatments were applied in a long-term experiment of organic management of mango (OMM) initiated in 2005 with a randomized block design with four replications. Two external areas, one with conventional mango cultivation (CMM) and the other a fragment of regenerating Caatinga vegetation (RCF), were used as reference areas. Soil samples were collected in the three management systems from the 0.00-0.05, 0.05-0.10, and 0.10-0.20 m layers, and the total organic carbon content and chemical fractions of organic matter were evaluated by determining the C contents of humin and humic and fulvic acids. Organic compost application significantly increased the contents of total C and C in humic substances in the experimental plots, mainly in the surface layer. However, compost 3 (50 % coconut bagasse, 40 % goat manure, 10 % castor bean residues) significantly increased the level of the non-humic fraction, probably due to the higher contents of recalcitrant material in the initial composition. The highest increases from application of the composts were in the humin, followed by the fulvic fraction. Compost application increased the proportion of higher molecular weight components, indicating higher stability of the organic matter.

Nitrate and potassium concentration in fertigated soil cultivated with wine vines.

In the semiarid region of Brazil the use of irrigation systems for applying fertilizers in horticulture is the primary means for incorporating nutrients in the soil. However, this technique still requires its use in wine vines to be assessed. In view of this, this study aimed to assess nitrate and potassium concentrations in soil fertigated with nitrogen and potassium fertilizers in 3 wine grape growing cycles. A field experiment was conducted with ?Syrah? wine grapes, in Petrolina, Pernambuco, Brazil; it assessed five nitrogen doses (0, 15, 30, 60 and 120 kg ha-1) and five K2O doses (0, 15, 30, 60 and 120 kg ha-1) applied by drip irrigation system with two emitters per plant, with a flow rate of 4 L h-1. The experimental design used was the factorial split-plot, making up 13 combinations arranged in 4 randomized blocks. Soil solution samples were collected weekly with the aid of porous cup extractors for all treatments and at depths of 0.4 and 0.6 m by determining nitrate and potassium concentrations and electrical conductivity. Increased levels of both nutrients in the irrigation water increased the availability of nitrate and potassium in the soil solution. The highest nitrate and potassium concentrations were found in the second growing cycle at both depths studied.

Methodology for climate risk assessment of maize intercropped with Brachiaria in the Cerrado of Brazil.

2015

Future climate change impacts on maize production in the Cerrado of Brazil.

2015

Stylosanthes guianensis cv. BRS Bela managed as organic fodder bank for supplementation of lactation crossbred cows in the Cerrado.

2016

Organic management of Brachiaria brizantha cv. Marandu pasture mixed with Stylosanthes spp. in the Cerrado.

2016

Genome wide association study for beef tenderness in Polled Nellore cattle.

2016

Comparative study of the antihypertensive effects of hexane, chloroform and methanol fractions of essential oil of Alpinia zerumbet in rats Wistar.

2015

The morphological characterization of the dry seeds and reserve mobilization during germination in Morinda citrifolia L.

2016

Mineralisation of the fungicide 14C-labelled metalaxyl fungicide in Brazilian soils.

Laboratory incubation experiments were carried out to estimate the mineralisation of metalaxyl 14C {N-(2-6 dimethyphenyl)-N-(methoxyacetyl) alanine methyl ester} in four Brazilian soils with different physico-chemical properties, at 3 and 30 ?g a.i. g-1. In the Petrolina sandy soil the mineralisation presented higher 14CO2 production rates, at two essayed concentrations, after 70 days. Microbiological studies were done to determine the numbers of bacteria, actinobacteria and fungi (CFU g-1 soil). In relation with other microbial community, bacterial population demonstrated to be a major component of the cultivable heterotrophic community after the application.of the compound. No detectable metabolites were found in this study. The results suggest that soil properties and application history may have a strong influence on the fungicide behavior in these soil samples.

Timing expression profile of carotenoids pathway genes in maize grains for characterization of landrace germoplasm from south Brazil.

2011

Nutritional technological characterization and secondary metabolites in stored carioca bean cultivars.

The recommendation of bean cultivars and the use of appropriate storage techniques allow the quality characteristics of these grains to be preserved for human consumption. The aim of this study was to characterize the effects of storage on three cultivars of the common carioca bean in raw form and to determine the relationships between storage time and technological quality parameters involved in the darkening and hardening of grains, the chemical composition of the beans and the presence of secondary metabolites. The experiment followed a completely randomized design (CRD) with a full factorial scheme consisting of two factors: bean cultivars, with three levels and storage time, with five levels. The color parameters and the storage times significantly differed between the cultivars. The cooking time, when compared to the water absorption index, indicated that the cultivars had, on average, a high percentage of moisture (>95%) and an average cooking time of 17 min., this applies to the control, while values increase during the storage time. Storage under ambient conditions led to a reduction in grain brightness parameters, characterized by darkening and hardening; no reduction in protein and mineral content; and an increase in iron, phosphorous, tannin, and phytic acid contents at 180 days.

Using a bespoke 'Omics' approach to devise a flexible new way to control Fusarium in wheat.

2016

Efficacy of fungicides for the control of Fusarium head blight in wheat: cooperative trials results - 2014 crop season.

2016

Methodology to determine the number of infection points of Gibberella zeae in wheat spikes.

2016