Organic residues and their impact on soil health,crop production and sustainable agriculture: A review including bibliographic analysis

Despite their potential as a sustainable source of soil nutrients and organic matter, waste organic residues are often discarded rather than utilized in agriculture. This review examines the current state-of-the-art in the application of organic residues in agricultural production systems by analysing trends and results in published research conducted on their use for soil health and crop production purposes. For this, a bibliographic analysis was conducted on 81 papers collected from the Web of Science database. Our research shows a growing trend in the field, particularly in recent years, with articles from India, China and the United States at the forefront. The most commonly evaluated organic residues were compost, animal manure, crop residues, municipal solid waste and biochar. Soil pH, bulk density and especially organic matter/total organic carbon (TOC) were the chemical, physical and biological attributes most frequently evaluated, respectively. This review indicates that the application of organic residues improves soil health, positively affecting crop productivity in crops such as maize, wheat and rice. However, further research is needed to address the potential risk of soil contamination from potentially toxic metals (PTMs) associated with organic residues, as well as to identify best practices to guarantee food safety and environmental preservation.     

Magnesium and zinc interaction in four soybean cultivars with different nutritional requirements

Abstract

In the last decades, soybean (Glycine max (L.) Merrill) was the crop with the highest acreage in Brazil. Soybean has been cropped under unfertile soils as sandy soils and those under pasture decaying where applying high fertilizer levels have significant responses. The presence of calcium (Ca) and magnesium (Mg) concentration in the upper layers promotes ions imbalanced concentration in soil solution because the soil acidity correction reduces the uptake of other cations as zinc (Zn). The objective of this study was to evaluate under nutritive solution conditions, the Mg influence in Zn distribution and mobilization into plants from four soybean cultivars with different nutritional requirements. The experimental design was complete randomized blocks in factorial scheme 4?×?2?×?4 being with four soybean cultivars (FT Estrela, DM Nobre, IAC 17, and IAC 15-1), two Mg rates (0.1 and 1.0?mmol?L^?1), four Zn rates (0, 1, 2, and 5?µmol?L^?1), and four replicates. The IAC 17 and FT Estrela cultivars with determinate growth and high nutritional requirements, and the IAC 15-1 and DM Nobre with tolerance to soils partially corrected, average fertility, or both were investigated. In the highest Mg rates, we verified increase in grain yield (GY) as well as in the Zn rates up to 2.0?µmol?L^?1. The Mg?×?Zn interaction was significant and the IAC 17 cultivar was the most responsive to Zn under nutritive solution. The foliar nutrient concentration was significantly modified by Mg rates. The Mg at 1.0?mmol?L^?1 presented the lowest nutrient concentration in soybean plants and increased the shoot dry weight yield (SDWY) in plant and grain no matter the nutritional requirement from every cultivar.     

Characteristics and Aquaculture Information Needs of Crayfish Farmers in Akwa-Ibom State,Nigeria

This study investigated the characteristics and aquaculture information needs of crayfish farmers in Akwa-Ibom State of Nigeria. Ninety crayfish farmers formed the sample for the study. Percentage, mean score, and multiple regression were used in data analysis. The findings show that the respondents had no extension contact and no access to crayfish and agriculture-related information. Information on adaptation to the effects of climate change on aquatic animals, especially crayfish, was needed by these farmers. Primary occupation, monthly income from crayfish enterprise, household size, and number of extension contacts were determinants of output on crayfish. The restriction of fishing activities on traditional festival days was a challenge, while the use of modern boats and durable nets were strategies for improving harvesting of crayfish.     

Tumescent local anesthesia with ropivacaine in different concentrations in bitches undergoing mastectomy: plasma concentration and post‐operative analgesia

ObjectiveTo compare two concentrations of ropivacaine administered for tumescent local anesthesia (TLA) in dogs undergoing mastectomy.Study designProspective randomized clinical study.AnimalsSeventeen bitches of various breeds, aged 12 ± 2 years and weighing 10 ± 6.5 kg requiring total unilateral or bilateral mastectomy.MethodsDogs were premedicated with acepromazine (0.04 mg kg^?1) and morphine (0.4 mg kg^?1) intramuscularly. Anesthesia was induced with propofol (2.5 mg kg^?1) and midazolam (0.2 mg kg^?1) intravenously, followed by intubation and maintenance with isoflurane and TLA. Dogs were randomly allocated to receive TLA either with 0.1% ropivacaine (group G1) or with 0.05% ropivacaine (group G05). TLA was performed by insertion of a multihole needle under the skin and infusion of ropivacaine and lactated Ringer’s solution at a fixed volume of 15 mL kg^?1. Ropivacaine concentrations in arterial blood were measured by high-performance liquid chromatography. Post-operative pain was assessed using two scales (University of Melbourne pain scale and a modified composite measure pain scale) and von Frey filaments, 4 hours after TLA and at 1 hour intervals until sensitivity was regained. A score above 30% of the maximum possible score was considered a positive indicator of pain.ResultsPeak plasma concentrations of ropivacaine were measured 240 minutes after TLA in G1. Low concentrations were measured in G05 for 60 minutes, with subsequent increase. Analgesic rescue and return of sensitivity occurred at 7 ± 2.3 and 7 ± 1.9 hours (mean ± SD) after TLA for G1 and G05, respectively.Conclusions and clinical relevanceTumescent local anesthesia with ropivacaine provided satisfactory post-operative analgesia that lasted for several hours, with no difference in duration between the concentrations. No serious side effects were attributed to TLA. Results indicated that 0.05% ropivacaine provided adequate analgesia for mastectomy, however, more studies are required to support this conclusion.     

Structure and function of an essential component of the outer membrane protein assembly machine

Integral beta-barrel proteins are found in the outer membranes of mitochondria, chloroplasts, and Gram-negative bacteria. The machine that assembles these proteins contains an integral membrane protein, called YaeT in Escherichia coli, which has one or more polypeptide transport-associated (POTRA) domains. The crystal structure of a periplasmic fragment of YaeT reveals the POTRA domain fold and suggests a model for how POTRA domains can bind different peptide sequences, as required for a machine that handles numerous beta-barrel protein precursors. Analysis of POTRA domain deletions shows which are essential and provides a view of the spatial organization of this assembly machine.     

Evaluation of Anti-Nociceptive and Anti-Inflammatory Activities of a Heterofucan from Dictyota menstrualis

Fucan is a term that defines a family of homo- and hetero-polysaccharides containing sulfated l-fucose in its structure. In this work, a heterofucan (F2.0v) from the seaweed, Dictyota menstrualis, was evaluated as an antinociceptive and anti-inflammatory agent. F2.0v (20.0 mg/kg) inhibits 100% of leukocyte migration into the peritoneal cavity after chemical stimulation. However, F2.0v does not alter the expression of interleukin-1 beta (IL-1β) and interleukin-6 (IL-6), as well as tumor necrosis factor alpha (TNF-α). F2.0v (20.0 mg/kg) has peripheral antinociceptive activity with potency similar to dipyrone. On the other hand, it had no effect on pain response on the hot plate test. Confocal microscopy analysis and flow cytometry showed that F2.0v binds to the surface of leucocytes, which leads us to suggest that the mechanism of action of anti-inflammatory and antinociceptive F2.0v is related to its ability to inhibit the migration of leukocytes to the site of tissue injury. In summary, the data show that F2.0v compound has great potential as an antinociceptive and anti-inflammatory, and future studies will be performed to further characterize the mechanism of action of F2.0v.     

Elevated [CO2] and warming increase the macronutrient use efficiency and biomass of Stylosanthes capitata Vogel under field conditions

Stylosanthes capitata Vogel is a C3 forage legume widely cultivated in tropical and subtropical pastures. However, the nutrient dynamics of this species under future climate change is unknown. Therefore, this study aimed to evaluate the nutrient content, nutrient accumulation, nutrient use efficiency and growth of S. capitata exposed to increased [CO₂] and temperature under field conditions using two levels of atmospheric [CO₂] (ambient and elevated—600 ppm) and two canopy temperature (ambient and elevated—2°C). Treatments were applied at field conditions, for 30 days, using a free-air carbon dioxide enrichment (FACE) and a free-air temperature-controlled enhancement (T-FACE) systems. Warming showed no effects on macronutrient content, but increased the accumulation of nitrogen, potassium, calcium, magnesium and sulphur, the nutrient use efficiency and root dry mass. Elevated [CO₂] alone had no effect on most of the parameters evaluated. However, the combination of elevated [CO₂] with warming improved the nutrient accumulation, nutrient use efficiency and whole-plant growth more than under isolated conditions of elevated [CO₂] or warming. Based on our short-term results, we concluded that an increment of atmospheric [CO₂] and temperature will benefit S. capitata growth, suggesting no alterations in the actual fertilizer programs for this species.     

The effect of lufenuron, a chitin synthesis inhibitor, on oogenesis of Rhodnius prolixus

The effects of lufenuron, a chitin synthesis inhibitor, on oogenesis of Rhodnius prolixus were evaluated. Lufenuron-treated females lay eggs that are pink, but change color with time, acquiring a gray color. The eggs are abnormal in shape and become dehydrated. The percentage of eggs that hatch is decreased compared with the eggs from non-treated females. Digestion of ovaries with KOH yielded an insoluble white material, which was identified as chitin based on infrared and proton NMR spectral analyses along with standard commercial chitin. Glucosamine was detected by HPLC as the major product of acid hydrolysis of the KOH-insoluble material prepared from the ovary. Furthermore, presence of chitin in ovary was confirmed through fluorescent microscopy technique using a wheat germ agglutinin probe and by re-treatment with Streptomyces griseus chitinase that resulted in reduction of chitin-derived fluorescence. Micrographs of ovaries, from animals treated with lufenuron, showed some space between the follicular epithelium and the oocyte membrane. The in vivo incorporation of radioactive N-acetylglucosamine into chitin was inhibited by the presence of lufenuron. These data suggest that chitin present in ovaries of R. prolixus is an important component of the eggs and is involved in oogenesis. Exposure to lufenuron reduces the size of oocytes, number of chorionated oocytes, and also the incorporation of N-acetylglucosamine into chitin in the ovaries. In addition, lufenuron-induced oosorption, decreased the number of eggs laid, modified egg shape and color and reduced the viability of the eggs. Therefore, chitin or chitin-like component of ovaries may be considered as a new target for controlling R. prolixus populations.     

Thermal and Chemical Properties of Gelatin from Tilapia (Oreochromis niloticus) Scale

ABSTRACT

Gelatin from the scale of Nile tilapia was extracted and characterized chemically, thermally, and structurally. Scales of Nile tilapia were subjected to acid pretreatment and extraction with water at 60°C. The process yielded 12.1% (m/m) on a dry basis. The 6.67% gelatin solution had a gel strength of 233.5 ± 14g. The amino acid composition revealed that 20.02% was comprised of imino acids and glycine (34.49%) as the most abundant amino acids. The scale gelatin had α1, α2, and β subunits and was thermally stable up to 200ºC. The Fourier transform infrared spectrum showed absorption in the regions of amides A, I, II, and III. The characterization of tilapia scale gelatin showed that the obtained product was similar to commercial gelatin, thereby demonstrating its potential application.