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251.
Honest error,precaution or alertness advertisement? Reactions to vertebrate pseudopredators in red‐nosed cuxiús (Chiropotes albinasus), a high‐canopy neotropical primate
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Adrian A. Barnett Tadeu de Oliveira Rafaela Fatima Soares da Silva Samara de Albuquerque Teixeira Pavel Tomanek Lucy M. Todd Sarah A. Boyle 《Ethology : formerly Zeitschrift fur Tierpsychologie》2018,124(3):177-187
Predation on primates is considered to have far‐reaching effects on the foraging and social ecology of a species. Primate species display a variety of responses to predator proximity and attack, ranging from active physical defense and mobbing, to flight and concealment. Warning calls are often given, and potentially threatening animals may be tracked, either actively or with head movements. Such behaviors take time that could be used for other activities. Accordingly, there should be strong selection to respond only to those species that represent a genuine threat. However, primates give defense‐based behaviors to non‐predator species. We tested the hypotheses that responses to pseudopredators are (i) precautionary calls made by individuals following the Dinner/Life Principle, or (ii) represent the ontogeny of species recognition. Of the species that ellicted a response from the cuxiús, 80% resembled a primate predator; 95% of the encounters that elicited a response from the cuxiús occurred when the distance between the pseudopredator and cuxiús was ≤20 m. In regard to the frequency of responses to pseudopredators, we found no difference between adults and juveniles (47.6% and 52.4%, respectively) and no differences between adult males and adult females (60% and 40% of the responses, respectively). However, reactions to pseudopredators were of shorter duration ( ± standard error (SE): 42.2 ± 15.9 s) than were reactions to actual predator species ( ± SE: 1,024.3 ± 329.1 s). There were only three instances where alarm calls were made to species that did not resemble predators, and 66.7% (N = 2) were made by adult cuxiús and only 33.3% (N = 1) were made by a juvenile cuxiú. Therefore, we found partial support for the Dinner/Life Principle hypothesis, but no support for the ontogeny hypothesis. Examination of such responses to pseudopredators in other primate and non‐primate species may help understand the evolution of such behaviors. 相似文献
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254.
Structure of the phosphopeptidomannans from flocculent and non-flocculent yeast Kluyveromyces lactis
Mariyati Bilang Fatima Attioui Vincent Loppinet Jean-Claude Michalski Roger Bonaly 《Carbohydrate research》1996,280(2):303-313
After extraction from whole cells, and purification by gel filtration, the chemical composition and molecular mass estimation of the cell-wall phosphopeptidomannan (PPM) showed no significant difference respectively between flocculent, weakly, very weakly and non-flocculent Kluyveromyces lactis yeast strains. However, when PPMs were tested as ligands of a lectin, extracted from the flocculent strain, the PPM isolated from the flocculent and weakly flocculent strain were recognized to a higher degree than those isolated from the non and very weakly flocculent strains. Acetolysis of PPM extracted from the four strains produced five oligosaccharide fractions corresponding to mono-, di-, tri-, penta-and hexa-saccharides. The flocculent strain was characterised by a high content of di-and penta-saccharides. The 1H NMR analysis of the oligosaccharides demonstrated that the flocculent strain contained equivalent levels of the two mannobioses: Man( 1 → 2)Man and Man( 1 → 3)Man and of the two mannotrioses Man( 1 → 2)Man( 1 → 2)Man and Man( 1 → 3)Man( 1 → 2)Man. In contrast, the non-flocculent and the very weakly flocculent strains contained a single type of mannobiose Man( 1 → 2)Man and one type of mannotriose Man( 1 → 2)Man( 1 → 2)Man. 相似文献
255.
Abdulrahman Nabeel Jaballah Maiy Poomakkoth Noufira Riaz Sadaf Abdelaziz Somaia Issa Aya Mraiche Fatima 《Molecular and cellular biochemistry》2016,420(1-2):21-28
256.
Antagonistic Effects of Trichoderma harzianum Isolates against Ceratocystis radicicola: pioneering a Biocontrol Strategy against Black Scorch Disease in Date Palm Trees
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Fatima A. Al‐Naemi Talaat A. Ahmed Resna Nishad Osman Radwan 《Journal of Phytopathology》2016,164(7-8):464-475
Date palm is an important subsistence crop in arid regions due to its ability to grow under adverse environmental conditions such as high temperature, salinity and drought. Nevertheless, ideal conditions for its growth and production are also favourable to fungal diseases such as black scorch disease caused by Ceratocystis radicicola. The aim of this study was to develop a method of biological control through the isolation, identification and examination of the effectiveness of bioagents in controlling black scorch disease. Twenty‐five isolates of Trichoderma spp. were isolated from the rhizosphere of healthy date palm trees and morphological, microscopic and molecular approaches confirmed the identity of 11 isolates as Trichoderma harzianum species complex (THSC). In vivo study, application of both spore suspension and culture filtrates of T. harzianum decreased the size of necroses caused by C. radicicola. Additionally, scanning electron microscopy (SEM) showed lysis of the hyphal pathogen and phialoconidia along with scattered aleurioconidia. Results from the volatile metabolic assay and SEM suggested potential roles of cell wall degradation enzymes and volatile substances produced by T. harzianum as two collective mechanisms leading to degrade the cell wall of the pathogen and inhibit fungal growth. Altogether, results from our study demonstrated the efficacy and utility of using bioagents to control black scorch disease which could improve date palm yield. 相似文献
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Fatima El Haskouri Hassan Bouziane Maria del Mar Trigo Mohamed Kadiri Mohamed Kazzaz 《Aerobiologia》2016,32(4):669-681
Ascospores are frequently found as airborne fungal spores and recognized in various areas as an important cause of respiratory allergies. The main objective of the study was to determine the relationship between airborne ascospores and meteorological parameters using multivariate canonical correspondence analysis (CCA) and Spearman correlation. The aerobiological monitoring of fungal spores was performed over 5 years (2009–2013) using a Burkard volumetric spore traps. Seven main types of ascospores were identified: Leptosphaeria, Pleospora, Venturia, Diatrype, Chaetomium, Sporormiella and Ascobolus. The CCA results showed that all applied variables accounted for 27.4 % of the total variance in the spore data in the 5 years. The largest contribution to the total variance was explained in this period by the maximum air temperature (10.3 %). The effect of meteorological factors varied among years. The highest values of the total variance in the spore data, explained by the statistically significant variables, were observed in 2012 (28.6 %), with the highest contribution to minimum relative humidity (8.0 %). Most ascospores showed positive and statistically significant correlation with relative humidity and rainfall. In contrast, ascospores of Chaetomium were negatively correlated with precipitation and the relative humidity and positively with temperature. Based on these results, epidemiological and allergological studies must deserve more attention to estimate the allergenic potential of the ascospores. 相似文献
259.
Nawal Zhar Khalid Naamani Abdelhi Dihazi Fatima Jaiti Abderrahim El Keroumi 《Physiology and Molecular Biology of Plants》2016,22(3):361-370
Argania spinosa (L.) Skeels is an endemic forest tree for Morocco. The phytochemical compounds evaluation of four different morphotypes of their fruit pulps was investigated. The total content of sugar, protein and phenolic compounds were monitored during three different stages of maturation in the semi-continental (Mejji) and littoral regions (R’zwa). Total sugars, proteins, phenolics increased up to the ripe stage of all argan fruit morphotypes in the two regions. Spherical shape had higher sugar and protein content than other morphotypes. A significant difference (p < 0.05), was demonstrated by Pearson’s test, between the different morphotypes at three stages studied for all the phytochemicals compounds. Likewise, ANOVA test established that the variation of this compounds was influenced by the stage of maturation and/or region of development and/or their interaction according to fruit shape. Results from this study revealed that the increase of these parameters level take place for the most part during the last stages of maturity which synchronize with fruit softening. Furthermore, our results showed information about the richness of argan fruit pulp in carbohydrates compounds and secondary metabolites as the possibility of their contribution in nutritive forage value especially at ripe stage. 相似文献
260.
In this study, 41 culturable endophytic bacteria were isolated from the roots and shoots of three wetland plants, Typha domingensis, Pistia stratiotes and Eichhornia crassipes, and identified by 16S rRNA gene sequencing. Textile effluent-degrading and plant growth-promoting activities of these endophytes were determined. The analysis of endophytic bacterial communities indicated that plant species had a pronounced effect on endophytic bacterial association and maximum endophytes (56.5%) were associated with T. domingensis. These endophytic bacteria mainly belonged to different species of the genera Bacillus (39%), Microbacterium (12%) and Halomonas (12%). Eight of the 41 strains showing maximum efficiency of textile effluent degradation also exhibited plant growth-promoting activities such as production of indole-3-acetic acid and siderophore, presence of 1-amino-cyclopropane-1-carboxylic acid deaminase, and solubilization of inorganic phosphorous. This is the first study describing the diversity and plant-beneficial characteristics of the textile effluent-degrading endophytic bacteria associated with wetland plants. T. domingensis showed better growth in textile effluent and also hosted maximum number of endophytic bacteria in roots and shoots. The interactions between T. domingensis and its associated endophytic bacteria could be exploited to enhance the efficiency of constructed wetlands during the remediation of industrial effluent. 相似文献