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Colletotrichum truncatum transmission via lima bean seeds
Get PDFAnthracnose is the primary disease in Phaseolus lunatus cultures, causing severe losses. Inoculation techniques are vital for assessing genotype resistance and control methods at the early stages of seedling development. This study aimed to compare inoculation methods and exposure times of a lima bean seed variety to Colletotrichum truncatum using a completely randomized 4x5 factorial design with five replications. Seed inoculation methods by direct contact with mycelium, mannitol water restrictor, and sucrose water restrictor and immersion in conidia suspension were compared and submitted to substrates containing the developed pathogen or not at exposure times of 0, 36, 60, 84, and 108 hours. Evaluations were made by analyzing the severity, incidence, and disease index for anthracnose and seedling physiological quality under greenhouse conditions. The inoculation method by direct contact with sucrose solute for 36 hours was the most suitable for C. truncatum inoculation in lima bean seeds, providing a higher transmission rate but slightly affecting their physiological parameters. C. truncatum damage to lima bean seed performance increased with longer exposure times, regardless of the inoculation method
Productivity and mortality, of Fusarium oxysporum f. sp. passiflorae in passionfruit vines brs rubi do cerrado, grafted onto different rootstocks
Get PDFThe use of scions grafted onto passionfruit vines has become an alternative to their cultivation in areas with a history of fusariosis. However, the combinations between the graft and rootstock can influence on the productivity and longevity of the passionfruit farm. The objective was to evaluate the productivity and mortality of the passionfruit cv BRS Rubi do Cerrado grafted onto three species of rootstock in Terra Nova do Norte-MT. The design was a randomized block with 4 treatments BRS Rubi do Cerrado (BRS-RC) seedling plant along with those grafted onto three species of rootstock: Passiflora gibertii, Passiflora alata; Passiflora nitida. The scions were grafted through a cleft graft and the planting performed after 70 days. The evaluation was made of the total number and weight of the fruits, along with productivity and mortality of plants. Results showed that the BRS-RC, grafted onto P. gibertii and P. nitida, presented the best performance for weight of fruits, number of fruits and productivity. The cultivar that was grafted onto different rootstocks presented higher productivity in regards to the seedling plant. The BRS-RC, grafted onto P. nitida, presented a zero-mortality rate over the 16.5 months of cultivation. The rootstocks P. nitida and P. gibertii were superior to those of P. alata in reducing mortality in the passionfruit vine by Fusarium oxysporum f. sp. passiflorae. The confirmation was made of the pathogen Fusarium oxysporum f. passiflorae isolated in the experimental area in scions of the BRS-RC inoculated at 70 days of age
Chemical constituents and in vivo preliminary evaluation of the toxicological activity of Ouratea spectabilis (OCHNACEAE) and Clitoria guianensis (Fabaceae) leaves
Get PDFClitoria guianensis and Ouratea spectabilis, found in the Brazilian Cerrado, are used in folk medicine, despite the few chemical and biological studies reported in the literature. The present study aims to investigate the toxicity and effect of extracts from both species on the microcrustacean Artemia salina, and to determine the chemical composition of the hexane extract of O. spectabilis leaves and the EtOAc fraction of C. guianensis leaves. Kaempferitrin, a flavonoid isolated from of the EtOAc fraction of C. guianensis leaves, was identified by chemical analysis. Analysis of the hexane extract of O. spectabilis leaves using gas chromatography-mass spectrometry (GC-MS) suggested the presence of twenty-five known substances. The Hex, EtOAc, and EtOH crude extracts of C. guianensis leaves exhibited high and moderate toxicity against Artemia salina, with median lethal dose values (LD50) of 43.7, 25.4, and 233.4 mg.L−1, respectively. The acetone extract of O. spectabilis leaves showed moderate toxicity against Artemia salina with an LD50 value of 115.13 mg.L−1.As espécies Clitoria guianensis e Ouratea spectabilis, encontradas no Cerrado brasileiro, são utilizadas na medicina popular, apesar de não apresentarem estudos químicos e biológicos reportados na literatura. O presente trabalho busca investigar a toxicidade frente ao microcrustáceo Artemia salina, dos extratos destas espécies, assim como a composição química do extrato hexânico das folhas de O. spectabilis e da fração EtOAc das folhas de C. guianensis. O estudo químico da fração EtOAc das folhas de C. guianensis resultou no isolamento de um flavonoide conhecido como Kaempferitrin. A análise do extrato hexânico das folhas de O. spectabilis, por CG-EM, sugere a presença de 13 substâncias conhecidas. Os extratos Hex, EtOAc e EtOH bruto de C. guianensis mostraram alta e moderada toxicidade frente a Artemia salina, respectivamente, com valores de dose letal (DL50) de 43.7, 25.4 e 233.4 mg.L-1. O extrato acetônico das folhas de O. spectabilis apresentou moderada toxicidade frente a Artemia salina com DL50 de 114.8 mg.L-1
Palynology and meiotic behavior of Genipa americana L., a species native to the Amazon
Get PDFGenipa americana L., commonly known as genipap, belongs to the Rubiaceae family. This study aimed to describe the pollen morphology of the species, evaluate its meiotic behavior and pollen viability, and provide information to help the maintenance and conservation of the species in its natural habitat. Flower buds were collected from 20 individuals in Alta Floresta and Matupá municipalities, Mato Grosso, Brazil. Pollen morphology was characterized using acetolysis and compared to existing literature. Meiotic and post-meiotic phases were analyzed using 2% acetocarmine stain, and pollen viability was estimated using Sudan IV, Alexander\u27s stain, Lugol\u27s solution (1%), and 2% acetocarmine stain. G. americana has medium-sized, 3-colporate pollen with reticulated exine and few meiotic irregularities. Acetocarmine stain showed the highest mean percentage of pollen viability (97.96%). Stain tests revealed significant differences, indicating high pollen viability and meiotic regularity. However, conservation and recovery of degraded areas are still necessary as there is no guarantee of successful reproduction due to factors associated with fragmentation, genetic drift, reduced gene flow, and inbreeding
Morphology of the brain base arteries of the giant anteater (Myrmecophaga tridactyla)
Get PDFThis study aimed to describe the brain base arteries of the Myrmecophaga tridactyla using ten cadavers of adults from this species, including five male and five female specimens. The arterial vascular bed was perfused via the thoracic aorta with a dyed natural latex solution, and the animals were fixed and preserved with a 10% formaldehyde buffered solution. The encephala were removed, and their vessels dissected. Basilar artery formation occurred by anastomosis of the thick ventral spinal artery with vertebral arteries. The basilar artery formed two arterial islands and gave bulbar and pontine branches, and cranial, middle, and caudal cerebellar arteries and ended by forking into its terminal branches, the caudal communicating arteries. The blood supply of the encephalon derived solely from the vertebrobasilar system, and the arterial circle of the brain was closed caudally and rostrally. The absence of participation of internal carotid arteries in encephalon irrigation, the island formations by the basilar artery, and the fusiform shape of the arterial circle of the brain are peculiar characteristics of the vascular anatomy of the brain base of M. tridactyla.O objetivo deste estudo foi descrever a anatomia do círculo arterial do cérebro de Myrmecophaga tridactyla. Foram utilizados neste estudo 10 cadáveres desta espécie, sendo cinco machos e cinco fêmeas adultos. O leito vascular arterial foi perfundido via aorta torácica com látex natural corado e os animais fixados e preservados com solução tamponada de formol a 10%. Os encéfalos foram removidos e seus vasos dissecados. A. basilar foi formada pela anastomose da caliborosa Artéria (A.) espinhal ventral com as artérias (Aa.) vertebrais. Em seu trajeto a A. basilar formou duas ilhas arteriais e emitiu ramos bulbares, pontinhos e as Aa. artérias cerebelares cranial, média e caudal e terminou bifurcando em seus ramos terminais, as artérias comunicantes caudais. O suprimento sanguíneo do encéfalo foi proveniente exclusivamente do sistema vértebro-basilar e o círculo arterial do cérebro foi fechado tanto caudal, quanto rostralmente. A ausência da participação das artérias carótidas internas na irrigação do encéfalo, a formação de ilhas no trajeto da A. basilar e o formato fusiforme do círculo arterial do cérebro são características peculiares da anatomia vascular da base do encéfalo do M. tridactyla
Agronomic performance of cassava fertilized with phosphorus doses
Get PDFWe have evaluated the agronomic performance of table cassava cultivars fertilized with phosphorus doses in the Brazilian Semiarid Region. Two agricultural crops were grown at the Rafael Fernandes Experimental Farm, Mossoró, RN, from June/2018 to April/2019 and from June/2019 to April/2020. The experimental design was in randomized blocks, arranged in subdivided plots, with four replications. In the plots, doses of phosphorus were applied (0, 60, 120, 180 and 240 kg P2O5 ha-1), and in the subplots, the table cassava cultivars (Água Morna, BRS Gema de Ovo, Recife and Venâncio). The following were evaluated: dry matter of leaf, stem, and commercial root; harvest index; commercial root number; commercial productivity and aerial part productivity. The cultivars used had high root and aerial part productivities indicating that their irrigated cultivation is appropriate under the conditions of the Semiarid region of Rio Grande do Norte. The cultivars Água Morna, BRS Gema de Ovo and Recife are more efficient in the use of phosphorus, obtaining high productivity even in the absence of phosphate fertilization. The cultivar Venâncio is more responsive to phosphate fertilization, as it needs an input of this nutrient to increase its productivity
Effectiveness of ultrasonic activation associated to glycolic acid on smear layer removal, dentin structure and bond strength to root dentin
Get PDFThis study evaluated the effects of ultrasonic activation (US) associated to glycolic acid (GA) on smear layer, dentin structure and bond strength (BS) of filling/restorative material to root dentin. The roots were used for antimicrobial activity, dentin structure and BS evaluation, being distributed into seven groups, according to irrigation protocols: G1:DW+US; G2:17% EDTA; G3:QMix; G4:17% GA; G5:17% EDTA+US; G6:QMix+US; G7:17% GA+US. Scanning electronic microscopy, transmission electronic microscopy and push-out were performed, with specific statistical analysis for each evaluation. The highest smear layer removal occured in Groups 6 and 7 (p<0.05), and the largest collagen dispersion in Group 7, being similar to Group 2 and 5 (p>0.05). The highest BS of filling and restorative material occurred in Groups 6 and 7, and Groups 5, 6 and 7, respectively, being similars between them (p>0.05). The use of GA+US promoted effective smear layer removal and dentin structure preservation, improving the BS of filling/restorative material to root dentin
Antibacterial activity of Mangifera indica seed extracts combined with common antibiotics against multidrug-resistant Pseudomonas aeruginosa and Acinetobacter baumannii isolates
Get PDFIn this project, we employed ethanolic (EMI) and aqueous (AMI) extracts of mango (Mangifera indica L., Anacardiaceae) fruit seeds as a modulator of antibiotic resistance against multidrug-resistant (MDR) Pseudomonas aeruginosa and Acinetobacter baumannii to evaluate natural compounds isolated from by-products or waste of edible plants. We also investigated the effect of these extracts alone and in combination with standard classes of antibiotics in the desired strains. M. indica seeds were processed and exploited using ethanol and water. The minimum inhibitory concentrations (MICs) of clinical isolates were examined against EMI and AMI extracts, followed by seven antibiotics of ceftazidime, ciprofloxacin, penicillin, amikacin, meropenem, ampicillin, and colistin. The checkerboard method evaluated the synergistic action between mango kernel extract (EMI) and seven antibiotics. EMI extract significantly revealed antimicrobial properties against MDR A. baumannii and P. aeruginosa with synergistic effects with the applied antibiotics. The considerable antibacterial efficacy of ethanolic extract of M. indica seeds can have great curative value as antibacterial drugs against infections caused by MDR P.aeruginosa and A. baumannii
Screening of lysine production by Escherichia coli and Klebsiella isolates at different carbon sources
Get PDFLysine is an essential amino acid that is not biologically manufactured in the body. Different chemical methods for lysine production are expensive and give low yields. The present study was conducted with the purpose to evaluate the biochemical production of lysine by different carbon sources using bacterial isolates. Three carbon sources namely glucose, sucrose, and fructose were used to evaluate the biochemical production of lysine by Escherichia coli and Klebsiella spp. isolates. Optimum incubation periods were between 48-96 hours. An extensive amount of lysine was produced by all of these isolates in L6 fermentation medium. Maximum lysine was produced by Klebsiella isolate K1 6.48 g/L after 96 hours of incubation by using glucose as carbon source followed by 6.0 g/L by Klebsiella isolates K3 after 72 hours of incubation when sucrose was used as a carbon source at 37 °C. Highest amount of lysine was produced at 96 hours by Klebsiella isolates in addition to E. coli. From all three carbon sources using Klebsiella isolates and E. coli, glucose showed better lysine production
Considering the role of the assassin snail Anentome helena as a biological control of Bithynia siamensis goniomphalos, the first intermediate host of Opisthorchis viverrini
Get PDFThis study aims to investigate whether the assassin snail Anentome helena may serve as a biological control agent of Bithynia siamensis goniomphalos, the 1st intermediate host of Opisthorchis viverrini. Experiments were carried out in the laboratory, and the results found that A. helena showed the variation and selection of mollusc prey. A. helena can consume B. siamensis goniomphalos, which is remarkable because this snail can compete with other snails and could be used as a biological control. The consumption rate of the predator was compared, and it was found that A. helena prefers to consume Indoplanorbis exustus, followed by Pomacea canaliculata, Melanoides tuberculata, Filopaludina sumatrensis speciosa, Lymnaea sp., and B. siamensis goniomphalos. This is the first report of an experimental study controlling B. siamensis goniomphalos using A. helena. Our data imply that A. helena can control the B. siamensis goniomphalos population with good results, especially in the absence of other snail species