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101.
Sipaúba-Tavares Lúcia H. Fernandes João B. K. Melo-Santos Gustavo L. Scardoeli-Truzzi Bruno 《International Aquatic Research》2019,11(2):125-134
International Aquatic Research - A trial evaluated the effectiveness of macrophytes, Azolla caroliniana (AAC) and Lemna minor (ALM) as a culture media for microalgae Ankistrodesmus gracilis, and... 相似文献
102.
Giorgio S. Senesi Ladislau Martin-Neto Paulino Ribeiro Villas-Boas Gustavo Nicolodelli Débora M. B. P. Milori 《Journal of Soils and Sediments》2018,18(4):1292-1302
Purpose
The objective of this review is to survey critically the results obtained by the application of laser-induced fluorescence spectroscopy (LIFS) and laser-induced breakdown spectroscopy (LIBS) to the evaluation of the humification degree (HD) of soil organic matter (SOM) directly in untreated, intact whole soils.Materials and methods
A large number of soils of various origin and nature, either native or under various cultivations, land use, and management, at various depths, have been studied to evaluate the HD of their SOM directly in intact whole samples. The LIFS spectra were obtained by either a bench or a portable argon laser apparatus that emits UV-VIS light of high power, whereas the LIBS spectra were obtained using a Q-switched Nd:YAG laser at 1064 nm.Results and discussion
The close correlations found by comparing HLIF values of whole soil samples with values of earlier proposed humification indexes confirmed the applicability of LIFS to assess the HD of SOM in whole soils. The high correlation found between HDLIBS values and HLIF values showed the promising potential of LIBS for the evaluation HD of SOM.Conclusions
The LIFS technique shows to be a valuable alternative to evaluate the HD of SOM by probing directly the whole solid soil sample, thus avoiding the use of any previous chemical and/or physical treatments or separation procedures of SOM from the mineral soil matrix. The emerging application of LIBS to evaluate the HD of SOM in whole soils appears promising and appealing due to its sensitivity, selectivity, accuracy, and precision.103.
Caroline Carvalho de Oliveira Fabiana Villa Alves Roberto Giolo de Almeida Érick Lemes Gamarra Severino Delmar Junqueira Villela Paulo Gustavo Macedo de Almeida Martins 《Agroforestry Systems》2018,92(6):1659-1672
The objective was to evaluate the animal thermal comfort indices from two integrated crop-livestock-forestry (ICLF) systems. For this, temperature–humidity index (THI), black globe temperature and humidity index (BGHI), and the radiant thermal load (RTL) were assessed. Two ICLF (ICLF-1 and ICLF-2) systems and one control system were established. On the ICLF systems, the arboreal component was the eucalyptus tree (Eucalyptus grandis × Eucalyptus urophylla; H13 clone), planted in simple wide-spaced rows. The ICLF-1 system had a tree spacing of 14 × 2 m with 357 trees per hectare, and the ICLF-2 had a tree spacing of 22 × 2 m with 227 trees per hectare. The control system had five scattered native trees per hectare, pertaining to Gochnatia and Dipteryx species. The forage component in all three systems was piatã-grass (Brachiaria brizantha cv. BRS Piatã). The experimental design was a randomized block in a sub-subplot design scheme with four replications. The presence of shade provided by the trees offered better conditions of animal comfort when compared with the condition of full sun. The ICLF-1 system, with higher tree density, provided better indicators for thermal comfort, THI, BGHI, and RTL when compared with the condition of full sun, while ICLF-2 was no different than ICLF-1 for BGHI. 相似文献
104.
Bioassays were conducted in stored grains to evaluate the combined use of the entomopathogenic fungus Beauveria bassiana, diatomaceous earth (DE) and fenitrothion against adults of Rhyzopertha dominica and Tribolium castaneum. The insecticide agents were applied to wheat as follows: the fungus at 1 × 108 conidia/kg of wheat, DE at 3 g/kg of wheat and fenitrothion at a rate of 0.15 ml/kg of wheat (25% of field dose rate). Surviving insects and progeny production were monitored at thirty-day intervals until four months. For both insect species, significantly less progeny was produced on wheat treated with fenitrothion and DE + B. bassiana formulations in comparison with controls. The effect of insecticides on the grain damage, germination power of wheat and bulk density was also evaluated. After four months, B. bassiana mixed with DE reduced the damaged insect grains by 50% in comparison with both fenitrothion and control treatments. Trials using DE caused a reduction in bulk density while there were no significant differences for germination testing between treatments. 相似文献
105.
Spinosad‐mediated effects on the walking ability,midgut, and Malpighian tubules of Africanized honey bee workers 下载免费PDF全文
106.
Sara Mello Pinho Giovanni Lemos de Mello Kevin M. Fitzsimmons Maurício Gustavo Coelho Emerenciano 《Aquaculture International》2018,26(1):99-112
Aquaponics is emerging as an alternative for high-health food production. Being able to identify the technical viability of non-conventional plants and fish species would help to increase the interest and possibilities in aquaponic systems. The goal of the present study was to evaluate the aquaponics production of two garnish species: scallion (S) and parsley (P), using effluents of pacu and red tilapia culture. Two aquaponics devices were used, differing according to the fish species, generating two different effluents. Thus, for plant performance, four treatments were evaluated in a factorial design (plant species and fish effluent as main factors), as followed: Pacu-S, Tilapia-S, Pacu-P, and Tilapia-P, with three replicates each, for 35 days. Fish performance was evaluated using Student’s t test. Each experimental device included a fish tank, filters, and six experimental units for the plants (floating rafts). Results indicated that feed conversion ratio (FCR) was higher in tilapia as compared to pacu (p < 0.05); however, fish productivity and survival were similar between species. Plant performance parameters were similar with no significant differences regardless of the fish effluent (p > 0.05), except for higher number of leaves per plant in scallion cultured using pacu effluent. Plant performance comparing both plant species indicated that scallion performed better as compared to parsley in all parameters. In addition, scallion also performed better related to the plant quality index. The results indicate that pacu presented a viable alternative for the aquaponics production, and regarding to the garnish, scallion performed better results as compared to parsley. 相似文献
107.
Characterization of field‐evolved resistance to Bacillus thuringiensis‐derived Cry1F δ‐endotoxin in Spodoptera frugiperda populations from Argentina 下载免费PDF全文
Desmi I Chandrasena Ana M Signorini Gustavo Abratti Nicholas P Storer Magdalena L Olaciregui Analiza P Alves Clinton D Pilcher 《Pest management science》2018,74(3):746-754
BACKGROUND
Transgenic maize (Zea mays L.) event TC1507 (Herculex® I insect protection), expressing Cry1F δ‐endotoxin derived from Bacillus thuringiensis var. aizawai, was commercialized in 2003 in the Americas. Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) susceptibility to Cry1F was monitored annually across several regions in Argentina using diagnostic concentration bioassays. Reduced performance of TC1507 maize against S. frugiperda was reported in 2013. A resistant population was established in the laboratory and the dominance of Cry1F resistance was characterized.RESULTS
During 2012–2015, high‐survivorship of several populations was observed in the resistance monitoring program. Reciprocal crosses of a Cry1F‐resistant population with a Cry1F‐susceptible population were evaluated to calculate effective dominance (DML) based on mortality levels observed at 100 µg/ml Cry1F. Two additional dominance levels (DLC and DEC) were calculated using lethal (LC50) or effective concentration (EC50) derived from concentration–response bioassays. Estimates indicated that Cry1F resistance in S. frugiperda in Argentina was either highly recessive (DML = 0.005) or incompletely recessive (DLC < 0.26 and DEC < 0.19).CONCLUSION
This study is the first documented confirmation and characterization of S. frugiperda Cry1F field‐evolved resistance in Argentina. The resistance to Cry1F in S. frugiperda populations collected in Argentina, is autosomal and incompletely recessive similar to the resistance reported in Brazil. © 2017 The Authors. Pest Management Science published by John Wiley © Sons Ltd on behalf of Society of Chemical Industry. 相似文献108.
109.
Ghasem Ali Parad Masoud Tabari Kouchaksaraei Gustavo Gabriel Striker Seyed Ehsan Sadati Kazem Nourmohammadi 《Scandinavian Journal of Forest Research》2016,31(5):458-466
Tolerance to flooding is crucial when thinking in promissory species for restoration of ecosystems prone to suffer soil water excess. In this study, we tested the flooding tolerance of two-years-old seedlings of Chestnut-leaved oak (Quercus castaneifolia C.A.Mey.) to determine whether it can be recommended for use in wetland restoration programs. Seedlings of Q. castaneifolia were subjected to three treatments: (1) control (C), (2) flooding for 60 days followed by a 42-day recovery period (F?+?R) and (3) continuous flooding for 102 days (F). Physiological performance, plant morphological changes and biomass accumulation were assessed. Results showed that, although net photosynthetic rates, stomatal conductance and transpiration decreased with prolonged flooding, when flood waters were removed, plants were able to recover their physiological activity (49–80% compared to controls). By contrast, when plants were continually flooded, their physiological activity decreased as well as the leaves experienced precocious senescence and wilting. Biomass responses paralleled physiological responses: leaf and root biomass were 42–49% higher under F?+?R treatment than under continuous flooding, and all plants under the F?+?R survived. Therefore, Q. castaneifolia appears as a promising species to be further studied when thinking re-vegetation of riverine areas and other temporarily flooded wetlands. 相似文献
110.
Physiological and biochemical differences among Ulmus minor genotypes showing a gradient of resistance to Dutch elm disease 下载免费PDF全文
M. Li R. López M. Venturas J. A. Martín J. Domínguez G. G. Gordaliza L. Gil J. Rodríguez‐Calcerrada 《Forest Pathology》2016,46(3):215-228
Dutch elm disease (DED) spread across Europe and North America in the 20th century killing most natural elm populations. Today, breeding programmes aim at identifying, propagating and studying elm clones resistant to DED. Here, we have compared the physiology and biochemistry of six genotypes of Ulmus minor of variable DED resistance. Leaf gas exchange, water potential, stem hydraulic conductivity and biochemical status were studied in 5‐year‐old trees of AB‐AM2.4, M‐DV2.3, M‐DV2 × M‐CC1.5 and M‐DV1 and 6‐year‐old trees of VA‐AP38 and BU‐FL7 before and after inoculation with Ophiostoma novo‐ulmi. Leaf water potential and net photosynthesis rates declined, while the percentage loss of hydraulic conductivity (PLC) increased after the inoculation in susceptible trees. By the 21st day, leaf predawn and midday water potential, stomatal conductance to water vapour and net photosynthesis rates were lower, and PLC was higher in trees of susceptible (S) genotypes inoculated with the pathogen than in control trees inoculated with water, whereas no significant treatment effect was observed on these variables in the resistant (R) genotypes. Fourier transform infrared spectroscopy analyses revealed a different biochemical profile for branches of R and S clones. R clones showed higher absorption peaks that could be assigned to phenolic compounds, saturated hydrocarbons, cellulose and hemicellulose than S clones. The differences were more marked at the end of the experiment than at the beginning, suggesting that R and S clones responded differently to the inevitable wounding from inoculation and repeated sampling over the experimental course. We hypothesize that a weak activation of the defence system in response to experimental wounding can contribute to the susceptibility of some genotypes to O. novo‐ulmi. In turn, the decline in shoot hydraulic conductivity and leaf carbon uptake caused by the infection further exacerbates tree susceptibility to the fungus. 相似文献