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11.
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Over the last decade, comparative molecular profiling studies between compatible and incompatible plant-pathogen interactions have shown that susceptible response of the host to a pathogen requires factors that promote disease development. In this study, we examined proteome profiles during a compatible interaction between wheat and stripe rust. A 2D-LC system (ProteomeLab PF2D) was used for protein separation and to compare the proteome from infected and control samples. More than 700 protein peaks at each time point were compared between pathogen- and mock-inoculated samples. Selected proteins, with significant differences in abundance were identified by nanoLC-ESI- MS/MS and generated spectra were searched against the wheat protein databases from UniProt, and NCBI and the Puccinia database from The Broad Institute. In total, the identified proteins comprised of 62 % wheat and 38 % Pst proteins. All identified proteins were searched by bioinformatics-based algorithms to detect their subcellular localization and signal peptide motifs which have the potential to catch the candidate effector proteins. The wheat proteins were classified based on their function. Although a compatible interaction, many wheat proteins, such as antioxidants, PRs and cold-responsive proteins, are implicated in defense and stress tolerance. On the pathogen side, 64 proteins were identified, and included some important pathogenicity proteins that can play role in pathogen virulence and suppress the host defense. In addition, we discovered that nine proteins have a signal sequence and three of the hypothetical fungal proteins, PGTG_11681T0, PGTG_07231T0 and CBH50687.1, have been tentatively identified as candidate effectors.  相似文献   
13.
Role of exogenously-applied silicon (Si) on antioxidant enzyme activities was investigated in wheat under drought stress using a completely randomized factorial design with four replications. Drought stress significantly enhanced activities of ascorbate peroxidase, peroxidase, superoxide dismutase and catalase, and elevated accumulation of osmotically active molecules, soluble sugars and proline. Si application further enhanced activities of enzymes involved in oxidative defense system and accumulation of osmotically active molecules in drought-stressed plants. Under drought stress conditions, water shortage decreased protein content in all cultivars; however, application of Si increased it. Pollen area ratio was lower than 1 for cvs. Shiraz and Marvdasht under drought, but greater than 1 for cvs. Chamran and Sirvan. Water-limited regimes resulted in decreased leaf Ψw in all cultivars, but Si supply was effective in improving Ψw under water-limited regimes. Water shortage increased leaf K, Mg, and Ca concentrations. Under drought stress, Si-treated plants had higher K concentration than the none-treated plants.  相似文献   
14.
Most of plant growth regulators are known to alleviate negative effects of osmotic stress on crop growth. To evaluate the effects of cycocel (CCC), as a growth regulator, on crop seed germination, early growth, and vegetative growth under osmotic stress conditions, a study was conducted under controlled conditions. Six crops, wheat, barley, maize, sunflower, safflower, and rapeseed were grown under five osmotic potentials (0, as non-stress, ?0.5, ?1.0, ?1.5, and ?2.0 MPa), which were raised from seeds treated with three CCC concentrations (0, 2.5, and 3.5 g l?1). Reduced germination, seedling and vegetative growth as well as enhanced leaf free proline and chlorophyll content index were observed under osmotic stress. The extent of these changes depended on the type of the used crops. Priming with optimum CCC concentration mitigated to great extent stress-induced adverse effects on these crops. The positive effect of CCC priming on wheat, maize, and rapeseed was observed only at moderate osmotic levels, whereas on barley and safflower the priming effects were found in all levels of osmotic stress. However, sunflower did not respond to CCC priming treatments which might have been due to its thick achene coat. CCC priming was found to be effective in diverting a major proportion of assimilates to root, because root to shoot dry weight ratio increased due to CCC application under all osmotic stress regimes. Since barley and safflower were found to be most responsive to CCC priming, further research for better understanding of mechanisms of CCC priming on their germination and vegetative growth is recommended.  相似文献   
15.
A TWINSPAN classification of 60 sample plots from the Khanikan forest (North of Iran) is presented. Plant types were determined from field observations and sample plot data arranged and analyzed in association tables. The types were defined on the basis of species patterns of presence, absence and coverage values. Vegetation was sampled with randomized-systematic method. Vegetation data including density and cover percentage were estimated quantitatively within each quadrate and using the two-way indicator species analysis. The objectives of the study were to plant type's classification for Khanikan lowland forest in North of Iran, Identification of indicator species in plant types and increase our understanding in regarding to one of Multivariate analysis methods (TWINSPAN). Five plant types were produced for the study area by TWINSPAN, i.e., Menta aquatica, Oplismenus undulatifolius, Carex grioletia, Viola odarata and Rubus caesius. Therefore, at each step of the process, the program identifies indicator species that show strongly differential distributions between groups and so can severe to distinguish the groups. The final result, incorporating elements of classification can provide a compact and powerful summary of pattern in the data set.  相似文献   
16.
This research was conducted in Khanikan forests located in lowland of Mazandaran province (North of Iran). Eighteen profiles were dug and several chemical, physical and biological soil properties were investigated. The soil properties evaluated were soil pH, bulk density, saturation moisture content, electrical conductivity, organic carbon, total nitrogen, cation exchangeable capacity, available phosphorous, soil texture, calcium carbonate content, number and biomass of earthworms, litter carbon and litter nitrogen. Principal Component Analysis (PCA) was used to identify the variation of soil properties. PCA, a technique which reduces the dimensionality of multivariate data by removing Interco relations among variables, has a number of useful applications in forest researches. The results showed significant relationships between some soil factors with PC1 and PC2 axes, also, among different soil factors, the distribution of forest types was most strongly controlled with some soil characteristics such as acidity, bulk density, texture, phosphorous, organic carbon, total nitrogen and cation exchangeable capacity.  相似文献   
17.
Abstract

In this paper, a time-varying student-t copula is used to capture information on price volatility dependence in the short-, medium-, and long-run horizon in the US market for frozen and fresh salmon, trout, tilapia and catfish. Using monthly data from July 1992 to March 2017, the volatility dynamics for these aquaculture species are assessed. The analysis allows indicating significant differences in the volatility relationships, depending on time-frequency. While short-run volatility has limited dependency, there is significant dependency in both the medium- and long-run, indicating that market integration is stronger in the long-run. The information is particularly important to buyers and producers utilizing the futures markets, as contracts are typically traded using a set of frequencies, and may help them manage and reduce price risk.  相似文献   
18.
This study was conducted to show that dietary supplementation of a fungus, Aspergillus awamori called Koji in Japan, reduces skeletal muscle protein breakdown and stimulates growth in broiler chickens. A total of 30 chicks at 15 days of age was divided into control and two treatment groups (10 birds per treatment). Control group was fed basal diet and treatment groups were fed the basal diets supplemented with A. awamori at levels of 0.05% and 0.2%. The birds were raised for 12 days from 15 to 27 days of age and then the effect on growth, organ weights and plasma 3‐methylhistidine concentration and digestibilities of protein and energy was evaluated. The messenger RNAs (mRNAs) of atrogin‐1, ubiquitin, proteasome, m‐calpain, µ‐calpain, β‐actin, myosin and pax‐7 in the breast muscle were also measured. Body weight gain and breast muscle weight were increased, although feed intake was decreased by the fungus and thus feed efficiency was increased. Protein and energy digestibilities were increased. Furthermore, plasma 3‐methylhistidine concentration was decreased by the fungus. The mRNAs of atrogin‐1, ubiquitin, proteasome, m‐calpain and µ‐calpain were all decreased. The mRNA of β‐actin but not myosin and pax‐7 was slightly increased by the fungus. In conclusion, feeding A. awamori improves growth performance because skeletal muscle proteolytic activity is reduced and digestibilities of energy and protein are increased.  相似文献   
19.
Depending on their source, concentration, chemical structure, and molecular weight, condensed tannins (CTs) form insoluble complexes with protein, which could lead to ruminal bypass protein, benefiting animal production. In this study, CTs from Leuceana leucocephala hybrid were fractionated into five fractions by a size exclusion chromatography procedure. The molecular weights of the CT fractions were determined using Q-TOF LC-MS, and the protein-binding affinities of the respective CT fractions were determined using a protein precipitation assay with bovine serum albumin (BSA) as the standard protein. The calculated number-average molecular weights (M(n)) were 1348.6, 857.1, 730.1, 726.0, and 497.1, and b values (the b value represents the CT quantity that is needed to bind half of the maximum precipitable BSA) of the different molecular weight fractions were 0.381, 0.510, 0.580, 0.636, and 0.780 for fractions 1, 2, 3, 4, and 5, respectively. The results indicated that, in general, CTs of higher molecular weight fractions have stronger protein-binding affinity than those of lower molecular weights. However, the number of hydroxyl units within the structure of CT polymers also affects the protein-binding affinity.  相似文献   
20.
Development and practical application of multicomponent copolymerisation systems, such as terpolymerisation, is an on-going process because even a small addition of a particular comonomer may have a significant impact on the desired property. Commonly, three separate pairs of binary polymerisation experiments are carried out to obtain monomer reactivity ratios (MRR) values that relates to the ternary polymerisation reactions. However, the reaction conditions in each binary system may not be representative of the whole ternary system. The error-in-variables model (EVM) method is a relatively recent statistical approach to solving multi-response parameter estimation problems, with the advantage that all MRR parameters can be directly estimated from terpolymerisation data. New ternary copolymers derived from n-butyl acrylate (nBA), glycidyl methacrylate (GMA) and tetrahydrofurfuryl acrylate (THFA) were synthesised in solution at 70±1 °C in the presence of benzoyl peroxide (BPO) as a free radical initiator. The terpolymers were characterised by 1H NMR, 13C NMR and FTIR spectroscopic techniques. The terpolymer compositions were determined using 1H NMR analysis. The polydispersities of the terpolymers with values between 1.66 and 1.85 suggest a strong tendency for chain termination by disproportionation. The glass transition temperatures of the terpolymers are found to be between those of the corresponding homopolymers and relative to their content. Increase in the nBA or THFA contents and decrease in the GMA content in terpolymers results in a decrease in the glass transition temperatures. The determination of MRR for the ternary system was obtained by employing the EVM model. Experimental terpolymerisation data agree well with calculations based on the Alfrey-Goldfinger equation and the unitary and binary azeotropes were calculated.  相似文献   
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