Autor: Moya, P. - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Antifungal activity of Trichoderma VOCs against Pyrenophora teres, the causal agent of barley net blotch
Autorzy:: Moya, P.
Girotti, J.R.
Toledo, A.V.
Sisterna, M.N.
Tematy:: biological control
biopesticide
fungi
gas chromatography
mass spectrometry
pathogen
Pyrenophora teres
Trichoderma
antifungal activity
volatile organic compound; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/65288.pdf Link otwiera się w nowym oknie
Opis:: Many species of Trichoderma produce secondary metabolites such as volatile organic compounds (VOCs) that reduce plant diseases and promote their growth. In this work we evaluated the antagonistic effects of VOCs released by eight strains of two Trichoderma species against Pyrenophora teres Drechsler, the causal agent of barley net blotch. Antagonism was estimated based on the percentage of mycelial growth inhibition according to the confronted cultures method. VOCs extraction and identification were performed by gas chromatography and mass spectrometry, through different methodologies for VOCs emitted by antagonists and pathogens alone or when confronted. VOCs produced by all Trichoderma strains inhibited mycelial growth of the pathogen in a range of 3 to 32%, showing weak and unpigmented mycelia with vacuolization. In addition, P. teres stimulated the release of VOCs by both Trichoderma species. The major groups of VOCs detected were sesquiterpenes, followed by diterpenes, terpenoids and eight-carbon compounds. This is the first report about characterization of volatiles emitted by Trichoderma in the presence of P. teres.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Grain discoloration in different genotypes of durum wheat (Triticum durum L.) in Argentina: associated mycobiota and peroxidase activity
Autorzy:: Cipollone, M.J.
Moya, P.
Martinez, I.
Saparrat, M.
Sisterna, M.
Tematy:: durum wheat
grain discoloration
mycobiota
peroxidase activity; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:: https://bibliotekanauki.pl/articles/2084746.pdf Link otwiera się w nowym oknie
Opis:: Wheat grain discoloration, a worldwide disease that lowers grain quality and decreases grain yield, does not have a single etiology. It has been proposed that it is a consequence of an abiotic mechanism, a response to environmental conditions or enzymatic activity. It has also been suggest that it is a biotic mechanism, a fungal infection principally by Alternaria spp. and Bipolaris sorokiniana. The present work was carried out to analyze the possible etiology of this disease in nine durum wheat genotypes from two localities of southern Buenos Aires province (Argentina) on two sowing dates. Incidence (percentage of grain discoloration) was recorded and mycobiota associated with this pathology was registered following ISTA rules. Peroxidase activity in an extract obtained from grains belonging to genotypes of the locality that showed the highest incidence was measured. The incidence among genotypes, localities and sowing dates varied, although the genotypes with the higher and lower values of incidence were the same for all the variables tested. The fungus Alternaria spp. was isolated the most frequently followed by Fusarium spp., while Bipolaris sorokiniana was found the least frequently. Peroxidase activity showed that all the treatments had similar levels of enzymatic activity, but there was no clear differentiation between controls either between genotypes with the lowest or the highest incidence values. This suggests that peroxidase activity did not have a clear relationship with grain discoloration. In this research, it is presumed that fungal infection is the main cause of this disease.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Mechanical properties of some granular agricultural materials used in silo design
Autorzy:: Moya, M.
Aguado, P.J.
Ayuga, F.
Wydawca:: Polska Akademia Nauk. Instytut Agrofizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/26147.pdf Link otwiera się w nowym oknie
Opis:: The aim of this research was to provide values for different material properties considered in either traditional or more recent numerical silo design methods. Different samples of granular agricultural materials commonly stored in silos were tested. Common geotechnical devices have been used in order to make the replications easier. Based on these experiments it was determined that the different material properties were not affected by the test velocity, except in the case of Poisson ratio. From a practical point of view, the test velocity correlates well with the sliding velocity of grain during discharge. The values obtained for material properties considered in traditional silo design methods were similar to those reported by other authors. No significant differences were observed in the results obtained when using either the square shear box or the circular shear cell. The same conclusion was reached when comparing the results from direct shear tests with preconsolidated and unconsolidated samples. This means that simplified devices and procedures can be used in agricultural grains against other products. Finally, a table with the recommended values for the different parameters determined for each sample tested was provided in this work.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Determination of the friction coefficients of chestnut (Castanea sativa Mill.) sawn timber
Autorzy:: Villar-Garcia, J.R.
Vidal-Lopez, P.
Corbacho, A.J.
Moya, M.
Tematy:: wood
mechanical properties
friction coefficient
direct shear test; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Agrofizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/2082657.pdf Link otwiera się w nowym oknie
Opis:: This work provides the values of both the static and the kinetic friction coefficients for chestnut (Castanea sativa Mill.) of Spanish origin. Knowledge concerning these coefficients has its main application in the study of agroindustrial structures and machinery with timber members in contact. This determination was developed taking into account the timber anisotropy to establish surfaces and directions of slipping. A modified direct shear test device was used to conduct the tests and reproduce the tribological system. This procedure was functional and reliable and considered suitable for standardizing the friction measurement between timber surfaces, since this device is widely distributed in geotechnical and materials laboratories and the European codes do not specify a procedure or device to carry it out. The average values obtained were 0.46 for the static coefficient and 0.33 for the kinetic one, without considering the surfaces and directions of slipping. These values ranged between 0.36 and 0.55 for the static friction coefficient and between 0.28 and 0.39 for the kinetic friction coefficient depending on the direction considered and also taking into account the anisotropy of the timber. A good correlation was obtained between both coefficients, thus allowing for the estimation of the kinetic coefficient from the static one.
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Defect Recovery in α-Fe e$\text{}^{-}$-irradiated at 300 K
Autorzy:: Dai, G. H.
Li, X. H.
Moser, P.
Moya, G.
Van Duysen, J. C.
Tematy:: 61.70.Bv
61.80.Fe
78.70.Bj; Pokaż więcej
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Powiązania:: https://bibliotekanauki.pl/articles/1928989.pdf Link otwiera się w nowym oknie
Opis:: Defect annealing recovery has been studied, by measuring positron lifetime spectra, in high-purity α-iron irradiated at 300 K with 3 MeV electrons to a fluency of 7 × 10$\text{}^{19}$ cm$\text{}^{-2}$. Vacancy clusters containing 6-10 single vacancies were observed immediately after irradiation during which they were possibly forming (the so-called "irradiation annealing"). With increasing temperature, the agglomerates continually grow in size at the expense of their concentration, giving rise to the formation of microvoids (> 15 vacancies). Also present were other types of defects, probably immobile vacancies trapped by impurity (e.g. carbon) atoms and dislocation/loops generated presumably from collapse of voids during the relatively high dose irradiation and/or the annealing. The immobile vacancies eventually became movable at around 350 K, supplying the growing clusters and thus leading to a stabilization in their concentration till around 500 K. Between 500 and 700 K, microvoids gradually evaporated, but the dislocation-associated defects were able to survive annealing at temperatures as high as 700 K. The void size and concentration and their evolution have been evaluated on the basis of both the to date theoretical and experimental studies. The temperature dependence was also, observed of positron trapping into vacancy agglomerates of various sizes.Za
Dostawca treści:: Biblioteka Nauki