Production of baruzeiro seedling in different protected environments and substrates

The high seedlings quality is essential for deployment of homogeneous orchards. This study evaluated the baruzeiro (Dipteryx alata Vog) seedlings formation on different substrates within protected environments. It was used substrates with100% of cattle manure; 100% of cassava stems; 100% of vermiculite; 50% of cattle manure + 50% of cassava stems; 50% of cattle manure + 50% of vermiculite; 50% of cassava stems + 50% of vermiculite; and + ⅓ of cattle manure + ⅓ of cassava stems + ⅓ of vermiculite. These substrates were tested in protected areas: greenhouse; black shade net of 50% shading; and aluminized thermo-reflective screen of 50% shading. A completely randomized experimental design with five replicates of four plants was adopted. Initially, data were submitted to analysis of individual variance of the substrates, in each environment of cultivation, then performing the evaluation of the residual mean square and the analysis of these environments together for comparison. The best substrate for baruzeiro seedlings was pure vermiculite. The substrates with 100% of manure and the substrate with 33.33% of the mixed studied materials can be used for seedlings formation. The environment with screen can be indicated for the production of baruzeiro seedlings, since it gave vigor to the seedlings.

Effect of plant-biostimulant on cassava initial growth

ABSTRACT Biostimulants are complex substances that promote hormonal balance in plants, favor the genetic potential expression, and enhance growth of shoots and root system. The use of these plant growth promoters in crops can increase quantitatively and qualitatively crop production. Therefore, the aim of this study was to evaluate the effect of a commercial biostimulant on the initial growth of cassava. The experiment was arranged in a 2 x 5 factorial design, corresponding to two cassava cultivars (Cacau-UFV and Coimbra) and five biostimulant concentrations (0, 4, 8, 12 and 16 mL L-1). At 90 days after planting, the characteristics leaf area, plant height, stem diameter, leaf number, total dry matter and dry matter of roots, stems and leaves were evaluated. The biostimulant promoted linear increases in plant height, leaf number, leaf area, total dry matter, dry matter of stems, leaves and roots. The cultivar Cacau-UFV had a higher growth rate than the cultivar Coimbra. The growth promoter stimulated the early growth of the cassava crop.

Hydrogen production from cassava processing wastewater in an anaerobic fixed bed reactor with bamboo as a support material

Attempting to associate waste treatment to the production of clean and renewable energy, this research sought to evaluate the biological production of hydrogen using wastewater from the cassava starch treatment industry, generated during the processes of extraction and purification of starch. This experiment was carried out in a continuous anaerobic reactor with a working volume of 3L, with bamboo stems as the support medium. The system was operated at a temperature of 36°C, an initial pH of 6.0 and under variations of organic load. The highest rate of hydrogen production, of 1.1 L.d-1.L-1, was obtained with application of an organic loading rate of 35 g.L-1.d-1, in terms of total sugar content and hydraulic retention time of 3h, with a prevalence of butyric and acetic acids as final products of the fermentation process. Low C/N ratios contributed to the excessive growth of the biomass, causing a reduction of up to 35% in hydrogen production, low percentages of H2 and high concentrations of CO2in the biogas.

Evaluation of elephant grass silage with the addition of cassava scrapings

The objective of this experiment was to evaluate the effects of adding cassava scrapings on gas and effluent losses, dry matter recovery, pH, contents of N-NH3, organic acids and volatile fatty acids and the bromatological composition of elephant grass silages. It was used a randomized complete design, with four levels of cassava scrapings (0, 7, 15 or 30% natural matter) each one with four replications per level. The grass was cut at 50 days of regrowth and ensiled in 15-L silos, equipped with a Bunsen valve to allow gas outflow. The gas losses decreased quadratically with the addition of cassava scrapings, whereas effluent losses decreased linearly. Dry matter recovery increased quadratically with the addition of cassava scrapings. Dry matter (DM) concentration increased but crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and hemicellulose (HEM) decreased linearly with the addition of cassava scrapings. The pH value and lactic acid concentration increased quadratically with the addition of cassava scrapings. Contents of N-NH3 and butyric acid decreased quadratically with the addition of cassava scrapings, whereas acetic acid content decreased linearly. Addition of cassava scrapings reduced gas and effluent losses and improved the fermentation profile of elephant grass silages and the level of 7% already ensures this improvement.

Alkaloids from Stems of Esenbeckia leiocarpa Engl. (Rutaceae) as Potential Treatment for Alzheimer Disease

Esenbeckia leiocarpa Engl. (Rutaceae), popularly known as guaranta, goiabeira, is a native tree from Brazil. Bioactivity-guided fractionation of the ethanol stems extract afforded the isolation of six alkaloids: leiokinine A, leptomerine, kokusaginine, skimmianine, maculine and flindersiamine. All isolated compounds were tested for acetyl cholinesterase inhibition, in vitro and displayed anticholinesterasic activity. The alkaloid leptomerine showed the highest activity (IC(50) = 2.5 mu M), similar to that of the reference compound galanthamine (IC(50) = 1.7 mu M). The results showed for the first time the presence of alkaloids leptomerine and skimmianine in E. leiocarpa (Engl.) with potent anticholinesterasic activity.

Use of Cassava Peel as Carbon Source for Production of Amylolytic Enzymes by Aspergillus niveus

Aspergillus niveus produced high levels of alpha-amylase and glucoamylase in submerged fermentation using the agricultural residue cassava peel as a carbon source. In static conditions, the amylase production was substantially greater than in the agitated condition. The optimized culture conditions were initially at pH 5.0, 35 degrees C during 48 hours. Amylolytic activity was still improved (50%) with a mixture of cassava peel and soluble starch in the proportion 1:1 (w/w). The crude extract exhibited temperature and pH optima approximately 70 degrees C and 4.5, respectively. Amylase activity was stable for 1 h at 60 degrees C, and at pH values between 3.0 and 7.0. The enzyme hydrolysed preferentially maltose, starch, penetrose, amylose, isomaltose, maltotriose, glycogen and amylopectin, and not hydrolysed cyclodextrin (alpha and beta), trehalose and sucrose. In the first hour of reaction on soluble starch, the hydrolysis products were glucose and maltose, but after two hours of hydrolysis, glucose was the unique product formed, confirming the presence in the crude extract of an alpha-amylase and a glucoamylase.

Microsatellite Polymorphisms in Cassava Landraces from the Cerrado Biome, Mato Grosso do Sul, Brazil

Using nine microsatellite loci, we investigated genetic structure and diversity in 83 Brazilian cassava accessions, including several landraces, in the Cerrado biome in Mato Grosso do Sul, Brazil. All nine loci were polymorphic, averaging 6.00 alleles per locus. Treating each of seven municipalities as a cassava group or population, they averaged 3.5 alleles per locus, with 97% polymorphic loci, high values for observed heterozygosity (0.32) and gene diversity (0.56). Total genetic variability was high (0.668), and most of this genetic variability was concentrated within municipalities (0.577). Cluster and structure analyses divided accessions into two major clusters or populations (K = 2). Also, a significant genetic versus geographic correlation was found (r = 0.4567; P < 0.0260). Migratory routes in the Cerrado are considered main contributors to the region`s high cassava diversity and spatial genetic structure, amplifying interactions between traditional farmers and the evolutionary dynamics of this crop.

Analyses of the Headspace Volatile Constituents of Aerial Parts (leaves and stems), Flowers and Fruits of Bidens gardneri Bak. and Bidens sulphurea (Cav.) Sch.Bip. Using Solid-Phase Microextraction

The present study describes the volatile composition of aerial parts (leaves and stems), flowers and fruits from Bidens gardneri and Bidens sulphurea. The first species is widely distributed in Pantanal (Brazil) and is a traditional medicinal plant, while the second species is widely distributed throughout Brazil. In all analyses, observed were constituents like bicycloelemene, alpha-copaene, beta-caryophyllene, germacrene D, bicyclogermacrene and others. However, some compounds were identified only in one part of the plants analyzed. These results indicated sonic differences in the composition of the plants studied and they were in agreement with data of literature.

Antibacterial activity of 15-deoxygoyazensolide isolated from the stems of Minasia alpestris (Asteraceae) against oral pathogens

This work reports the isolation of the sesquiterpene lactone 15-deoxygoyazensolide from the stems of Minasia alpestris and the evaluation of its antimicrobial activity against the following oral pathogens: Enterococcus faecalis, Streptococcus salivarius, Streptococcus sobrinus, Streptococcus mutans, Streptococcus mitis, Streptococcus sanguinis, and Lactobacillus casei. Despite the cytotoxicity and genotoxicity of other sesquiterpene lactones of the furanoheliangolide-type, our results revealed that this compound exhibits low antibacterial activity against the evaluated oral pathogens; however, an interesting selectivity against E. faecalis (minimum inhibitory concentration [MIC] = 40 mu g mL(-1)) and S. sobrinus (MIC = 60 mu g mL(-1)) was observed.

Fermentative production of hydrogen from cassava processing wastewater by Clostridium acetobutylicum

This work reports on the effect of initial substrate concentration on COD consumption, pH, and H(2) production during cassava processing wastewater fermentation by Clostridium acetobutylicum ATCC 824. Five initial COD wastewater concentrations, namely 5.0, 7.5, 10.7, 15.0, and 30.0 g/L, were used. The results showed that higher substrate concentrations (30.0 and 15.0 COD/L) led to lower H(2) yield as well as less efficient substrate conversion into H(2). On the other hand, initial COD concentrations of 10.7, 7.5 and 5 g/L furnished 1.34, 1.2 and 2.41 mol H(2)/mol glucose, with efficiency of glucose conversion into H(2) of 34, 30, and 60% (mol/mol), respectively. These results demonstrate that cassava processing wastewater, a highly polluting effluent, can be successfully employed as substrate for H(2) production by C acetobutylicum at lower COD concentrations. (C) 2011 Elsevier Ltd. All rights reserved.

A review of the flower characteristics of Geraldton waxflower and factors influencing their abscission from harvested stems

Geraldton waxflower (Chamelaucium uncinatum Schauer) is Australia's most economically important cut-flower export. Its small, attractive flowers make it particularly suitable as a filler in floral arrangements. However, postharvest bud and flower abscission is a major problem during transport, handling and marketing. Abscission may be caused by wound-induced endogenous ethylene production brought about by flower tissue infection with fungal pathogens such as Botrytis cinerea. Botany and postharvest characteristics are discussed in relation to flower abscission and how resultant postharvest losses may be minimised.

Leaf consumption and duration of instars of the cassava defoliator Erinnyis ello (L., 1758) (Lepidoptera, Sphingidae)

The objectives of this research were to evaluate leaf consumption and the developmental time of the larvae of Erynnyis ello (L., 1758) (Lepidoptera, Sphingidae) reared on cassava, in order to obtain information for the integrated management of this pest. The larvae were reared on excised cassava leaves in Petri dishes and later in gerbox, and kept in chambers at 24 ± 2 ºC and 75 ± 10% RH. The total leaf area consumed by the larva to complete its development was 589.67 cm2; each of the five instars consumed, respectively: 1.89 cm2; 5.74 cm2; 17.48 cm2; 76.66 cm2; and 487.90 cm2. The consumption by the first three instars was insignificant, and did not reach 5% altogether; the 4th represented 13%; the 5th presented a consumption significantly higher, about 82.7%. The total time for the larval development was 22.61 days, and the duration for each of the five larval instar was, respectively: 4.35; 3.19; 3.32; 4.52; and 4.94 days. The pre-pupal period lasted 2.29 days. Since the highest consumption is by the 5th instar larva, the control should be applied before this age to avoid heavier damages to the cassava crop.

Post-harvest conservation of organic strawberries coated with cassava starch and chitosan

The strawberry is as non-climacteric fruit, but has a high post-harvest respiration rate, which leads to a rapid deterioration at room temperature. This study aimed to evaluate the application of biodegradable coating on postharvest conservation of organic strawberries, cv. Camarosa, packed in plastic hinged boxes and stored at 10ºC. The treatments consisted of: a) control; b) 2% cassava starch; c) 1% chitosan; and d) 2% cassava starch + 1% chitosan. Physical and chemical characteristics of fruits were evaluated at 3, 6 and 9 days of storage, and microbiological and sensory analyses were carried out at the end of the storage period. The treatments influenced positively the post-harvest quality of organic strawberries. The coating cassava starch + chitosan provided the best results, with less than 6% of loss in fruit mass, lower counts of yeast and psychrophilic microorganisms and the best appearance according to the sensory analysis.

The role of ascorbate peroxidase, guaiacol peroxidase, and polysaccharides in cassava (Manihot esculenta Crantz) roots under postharvest physiological deterioration

Abstract This study aimed to investigate the role of ascorbate peroxidase (APX), guaiacol peroxidase (GPX), polysaccharides, and protein contents associated with the early events of postharvest physiological deterioration (PPD) in cassava roots. Increases in APX and GPX activity, as well as total protein contents occurred from 3 to 5 days of storage and were correlated with the delay of PPD. Cassava samples stained with periodic acid-Schiff (PAS) highlighted the presence of starch and cellulose. Degradation of starch granules during PPD was also detected. Slight metachromatic reaction with toluidine blue is indicative of increasing of acidic polysaccharides and may play an important role in PPD delay. Principal component analysis (PCA) classified samples according to their levels of enzymatic activity based on the decision tree model which showed GPX and total protein amounts to be correlated with PPD. The Oriental (ORI) cultivar was more susceptible to PPD.

UV-visible scanning spectrophotometry and chemometric analysis as tools for carotenoids analysis in cassava genotypes (Manihot esculenta Crantz)

In this study, the metabolomics characterization focusing on the carotenoid composition of ten cassava (Manihot esculenta) genotypes cultivated in southern Brazil by UV-visible scanning spectrophotometry and reverse phase-high performance liquid chromatography was performed. Cassava roots rich in -carotene are an important staple food for populations with risk of vitamin A deficiency. Cassava genotypes with high pro-vitamin A activity have been identified as a strategy to reduce the prevalence of deficiency of this vitamin. The data set was used for the construction of a descriptive model by chemometric analysis. The genotypes of yellow-fleshed roots were clustered by the higher concentrations of cis--carotene and lutein. Inversely, cream-fleshed roots genotypes were grouped precisely due to their lower concentrations of these pigments, as samples rich in lycopene (redfleshed) differed among the studied genotypes. The analytical approach (UV-Vis, HPLC, and chemometrics) used showed to be efficient for understanding the chemodiversity of cassava genotypes, allowing to classify them according to important features for human health and nutrition.