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1.
Anim Welf ; 33: e28, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38828436

RESUMO

Human evaluation of animal emotional expressivity can inform animal welfare. Qualitative Behavioural Assessment (QBA) has been applied to domesticated and some non-domesticated animals, but its use in primates is limited despite their emotional expressivity. We aimed to develop and apply a QBA for bonobos (Pan paniscus) through two consecutive studies. We applied Free Choice Profiling (FCP) and the Fixed List methodology, respectively, in Study 1 and 2, and invited students and bonobo experts to rate video clips of zoo-living bonobos of different sexes and age classes, and before and after moving to a new enclosure. In Study 1, students described dimension 1 as ranging from 'quiet/calm' to 'angry/active' and dimension 2 from 'sad/anxious' to 'happy/loving'. Experts described dimension 1 ranging from 'quiet/relaxed' to 'nervous/alert' and dimension 2 from 'nervous/bored' to 'playful/happy'. Using a fixed list of descriptors, informed by findings from Study 1, students in Study 2 described dimension 1 as ranging from 'quiet/calm' to 'agitated/frustrated', and dimension 2 from 'sad/stressed' to 'happy/positively engaged'. Experts described dimension 1 as ranging from 'quiet/calm' to 'active/excited', and dimension 2 from 'sad/bored' to 'happy/positively engaged'. Students scored adults as more 'calm/quiet' and experts scored subadults as more 'happy/positively engaged'. Additionally, experts in Study 2 rated bonobos as more 'active/excited' in their new enclosure. Reliability was moderate to good for the dimensions. Additionally, animal-directed empathy of observers influenced QBA scores. This is the first time, FCP has been successfully used as a method to study primate emotional expressivity. Our findings show the promise of employing QBA in primate studies and in industry, with validation of additional metrics to enable its use for welfare-monitoring purposes.

2.
Zoo Biol ; 35(6): 467-473, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27623487

RESUMO

Ensuring welfare in captive wild animal populations is important not only for ethical and legal reasons, but also to maintain healthy individuals and populations. An increased level of social behaviors such as aggression can reduce welfare by causing physical damage and chronic stress to animals. Recently, cortisol in hair has been advanced as a non-invasive indicator to quantify long-lasting stress in many species. The sensitivity of social behavior and hair cortisol concentration was evaluated in several groups of dorcas gazelles (Gazella dorcas). Four different groups of gazelles from three different zoos were observed and the expression of intra-specific affiliative and negative social behaviors was assessed across the different groups. Hair samples were taken from sub-groups of animals and analyzed for cortisol concentrations. Significant differences between groups of dorcas gazelles were found in frequency of negative social behavior and hair cortisol concentration. Despite the low sample size, these two parameters had a positive Spearman correlation coefficient (rs = +0.80, P = 0.20). These results suggest that hair cortisol levels are sensitive to differences in the social structure of dorcas gazelles. Zoo Biol. 35:467-473, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Agressão/fisiologia , Criação de Animais Domésticos/métodos , Bem-Estar do Animal , Animais de Zoológico , Antílopes/fisiologia , Cabelo/química , Hidrocortisona/metabolismo , Animais , Antílopes/psicologia , Hidrocortisona/análise
3.
Neotrop Entomol ; 53(4): 917-928, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38940947

RESUMO

Granuloviruses (GVs) Betabaculovirus associated with the fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), especially those of the type I, have scarcely been studied. These GVs might be an effective alternative for the biocontrol of this insect. In this study, the native GVs SfGV-CH13 and SfGV-CH28 were isolated from FAW larvae and characterized for morphology, molecular traits, and insecticidal activity. The elapsed time between symptomatic infection of larvae and stop feeding as well as the weight of larvae before death or prior to pupation were also evaluated. Both GVs had ovoid shape and a length of 0.4 µm. They had the same DNA restriction profiles and their genome sizes were about 126 kb. The symptomatic infection with the tested GVs mainly caused flaccidity of larva body and discoloration of integument. The integument lysis was only observed in 8% of infected larvae. Infected larvae gradually stopped feeding. Overall, these symptoms are characteristic of infections caused by type I GVs, which are known as monoorganotropic or slow-killing GVs. The median lethal dose (LD50) values for SfGV-CH13 and SfGV-CH28 isolates were 5.4 × 102 and 1.1 × 103 OBs/larva, respectively. The median lethal time (LT50) ranged from 17 to 24 days. LT50 values decreased as the viral dose was increased. The elapsed time from symptomatic infection until pupation and body weight of larvae (third instar) were higher with SfGV-CH28 than SfGV-CH13. Both granulovirus isolates were able to kill the FAW larvae from the 12th day.


Assuntos
Granulovirus , Larva , Spodoptera , Animais , Spodoptera/virologia , Granulovirus/genética , Larva/virologia
4.
Animals (Basel) ; 13(12)2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37370476

RESUMO

Zoological institutions, such as zoos and aquariums, have made animal welfare a top priority, as it is not only a moral obligation but also crucial for fulfilling their roles in education and conservation. There is a need for science-based tools to assess and monitor animal welfare in these settings. However, assessing the welfare of zoo animals is challenging due to the diversity of species and lack of knowledge on their specific needs. This review aims to discuss the advantages and disadvantages of existing methodologies for assessing zoo animal welfare through: (1) A critical analysis of the main approaches to zoo animal welfare assessment; (2) A description of the most relevant animal-based welfare indicators for zoo animals with a particular focus on behavioural and physiological indicators; and (3) An identification of areas that require further research.

5.
Animals (Basel) ; 12(21)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36359126

RESUMO

Self-directed behaviours (SDBs) are widely used as markers of emotional arousal in primates, and are commonly linked to negative arousal, or are used as indicators of stress or poor welfare. However, recent studies suggest that not all SDBs have the same function. Moreover, lateralisation in the production of these behaviours has been suggested to be associated with emotional processing. Hence, a better understanding of the production and the asymmetry of these displacement behaviours is needed in a wider range of species in order to confirm their reliability as indicators of emotional arousal. In the current study, we experimentally evaluated the production and asymmetry of SDBs in zoo-housed bonobos during two cognitive touchscreen tasks. Overall, nose wipes were most commonly observed, followed by gentle self-scratches, and rough self-scratches. The rates of nose wipes and rough self-scratches increased with incorrect responses, suggesting that these behaviours indicate arousal and possibly frustration. Rough self-scratching was additionally more directed towards the left hemispace after incorrect responses. In contrast, gentle self-scratching increased after correct responses in one study, possibly linking it with positive arousal. We also tested if left-handed bonobos showed greater behavioural reactivity towards incorrect responses, but found no evidence to confirm this hypothesis. Our results shed light on potential different mechanisms behind separate SDBs. We therefore provide nuance to the use of SDBs as indicator of emotional arousal in bonobos.

6.
Plants (Basel) ; 11(7)2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35406854

RESUMO

Streptomyces are recognized as antipathogenic agents and plant-growth-promoting rhizobacteria. The objective of this study was to evaluate the capacities of four antifungal Streptomyces strains to: produce the substances that are involved in plant growth; solubilize phosphates; and fix nitrogen. The effects of the volatile organic compounds (VOCs) that are emitted by these strains on the growth promotion of Arabidopsis thaliana and Phaseolus vulgaris L. (var. Pinto Saltillo) seedlings were also tested. All of the Streptomyces strains produced indole-3-acetic acid (IAA) (10.0 mg/L to 77.5 mg/L) and solubilized phosphates, but they did not fix nitrogen. In vitro assays showed that the VOCs from Streptomyces increased the shoot fresh weights (89-399%) and the root fresh weights (94-300%) in A. thaliana seedlings; however, these effects were less evident in P. vulgaris. In situ experiments showed that all the Streptomyces strains increased the shoot fresh weight (11.64-43.92%), the shoot length (11.39-29.01%), the root fresh weight (80.11-140.90%), the root length (40.06-59.01%), the hypocotyl diameter (up to 6.35%), and the chlorophyll content (up to 10.0%) in P. vulgaris seedlings. 3-Methyl-2-butanol had the highest effect among the ten pure VOCs on the growth promotion of A. thaliana seedlings. The tested Streptomyces strains favored biomass accumulation in A. thaliana and P. vulgaris seedlings.

7.
Animals (Basel) ; 11(7)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209437

RESUMO

Decisions on environmental enrichment programmes are sometimes based on the assumption that non-natural or artificial looking items negatively affect visitor experiences. In this study, we developed a questionnaire to assess zoo visitor attitudes towards enrichment appearance in an outdoor walk-through enclosure for ring-tailed lemurs (Lemur catta). Naturalistic and artificial looking enrichment items were alternately provided in the enclosure. A total of 371 visitors filled out the questionnaire: 174 in the naturalistic and 197 in the artificial conditions. Both researchers and visitors conducted behavioural observations of the lemurs. Our results suggest that the appearance of the items did not have an effect on visitor attitudes and that visitors recognised both naturalistic and artificial items as enriching for the animals. Moreover, the behaviour and visibility of the lemurs had a greater effect on the visitors' attitudes. We suggest that during the design of enrichment items, less concern should be placed on the appearance of the items and more on their effect on animal behaviour. Ultimately, this would improve both animal welfare in captivity and the visitor experience.

8.
Animals (Basel) ; 11(11)2021 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-34827780

RESUMO

A top priority of modern zoos is to ensure good animal welfare (AW), thus, efforts towards improving AW monitoring are increasing. Welfare assessments are performed through more traditional approaches by employing direct observations and time-consuming data collection that require trained specialists. These limitations may be overcome through automated monitoring using wearable or remotely placed sensors. However, in this fast-developing field, the level of automated AW monitoring used in zoos is unclear. Hence, the aim of this systematic literature review was to investigate research conducted on the use of technology for AW assessment in zoos with a focus on real-time automated monitoring systems. The search led to 19 publications with 18 of them published in the last six years. Studies focused on mammals (89.5%) with elephant as the most studied species followed by primates. The most used technologies were camera (52.6%) and wearable sensors (31.6%) mainly used to measure behaviour, while the use of algorithms was reported in two publications only. This research area is still young in zoos and mainly focused on large mammals. Despite an increase in publications employing automated AW monitoring in the last years, the potential for this to become an extra useful tool needs further research.

9.
Front Vet Sci ; 8: 574250, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33681319

RESUMO

Many factors can lead to an inadequate development of piglets during their first days of life, including poor maternal behavior, which can be due to pain caused by farrowing, and reduced colostrum ingestion. This study investigates the action of meloxicam administered orally at farrowing on piglet weight gain and immunity transfer. Thirty-five multiparous sows were divided into two groups and treated with 0.4 mg/kg of oral meloxicam (oral meloxicam group; n = 18) or with a mock administration (control group; n = 17). A total of 382 piglets were individually weighed on the farrowing day (day 0), as well as on days +9 and +20. Immunoglobulin G (IgG) and A (IgA) concentrations in piglet serum and in sow's saliva, colostrum and milk were measured. Additionally, Interleukin-2 (IL-2), Interleukin-4 (IL-4) and Interferon gamma (IFN-⋎) in serum of piglets and in sow's milk or colostrum were studied. All samples were obtained on days +1, +9, and +20. Piglets from sows in the oral meloxicam group tended to grow faster from day +9 to day +20 than did piglets from control sows (p = 0.059), and this difference was also observed in piglets with low body weight (BW) at birth (p = 0.056). The oral meloxicam group sows tended to increase the colostrum levels of IgA and IgG, as compared with control sows on day +1 (p = 0.068 and p = 0.072, respectively). IgA levels in piglet serum from the oral meloxicam group were significantly higher than in the control group on day +1 and +9 (p = 0.019 and p = 0.011 respectively). Furthermore, IL-2 and IL-4 levels in the serum of piglets from sows in the oral meloxicam group tended to be higher than that in the control group on day +9 (p = 0.078 and 0.056, respectively). The administration of meloxicam orally at the beginning of farrowing in multiparous sows increased immunoglobin and cytokine concentrations in colostrum, improving both humoral and cellular immune response of piglets. Pre-weaning growth of piglets born with a low BW improved in the meloxicam-treated group.

10.
Sci Rep ; 11(1): 7905, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846457

RESUMO

Cortisol is often measured as a marker for stress. Therefore, a profound validation of the time-lag between the stressor and the increase and peak in cortisol levels is needed. No study measured both the urinary and salivary cortisol time-lag after a psychological stressor. In this study, we used a frequent sampling study design to (1) describe the urinary and salivary cortisol pattern during a control day; and (2) characterize the induced excretion pattern of urinary and salivary cortisol after a psychological stressor in six zoo-housed bonobos. Liquid chromatography-tandem mass spectrometry was used to analyze 71 urine and 162 saliva samples collected on a control and a test day. We found that the time-lag between the stressor and the maximal cortisol concentration was similar in urine and saliva (160 min after the stressor). However, salivary cortisol after the stressor did show a faster and steeper increase than urinary cortisol. We also show inter-individual variation in the baseline and stress levels of cortisol, which should be considered in future cortisol studies. Our research highlights the importance of validation studies to confirm relevant sampling windows for cortisol sampling in order to obtain biologically meaningful results.


Assuntos
Hidrocortisona/urina , Pan paniscus/psicologia , Pan paniscus/urina , Saliva/química , Estresse Psicológico/urina , Animais , Feminino , Modelos Lineares , Masculino , Fatores de Tempo
11.
Animals (Basel) ; 11(7)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34359202

RESUMO

The evaluation of zoo animals' personalities can likely lead to a range of benefits, including improving breeding success, creating stable social groups, and designing and developing environmental enrichment programmes. The goal of this study was to use caretakers scores to evaluate personality in bottlenose dolphins and to assess the reliability of scores within each rater and among raters from each centre. To this end, 24 caretakers from 3 countries (Spain, France, and Argentina), including a total of 5 dolphinariums and 6 groups of dolphins, used a questionnaire based on the Five-Factor Model of Personality to score bottlenose dolphins on a number of personality traits in three different contexts. Each caretaker evaluated the animals under their care twice, ensuring that raters did not share thoughts nor impressions with other raters. Our findings showed a good degree of agreement between each rater's scores and a fair degree of agreement among scores of raters from the same centre. We also identified which raters and centres had significant mean score differences and detected that 4 out of 24 raters from two different centres showed such differences systematically. The evaluation of raters' reliability and the identification of particular inconsistent raters and centres is critical to make more appropriate and realistic management decisions that, in turn, directly impact animals' welfare.

12.
Antibiotics (Basel) ; 9(8)2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32722499

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is a prevalent nosocomial pathogen, causing a wide range of diseases. The increased frequency of MRSA isolates in hospitals and the emergence of vancomycin resistance have sparked the search for new control strategies. This study aimed to characterize sixty-seven MRSA isolates collected from both infected patients and asymptomatic carriers in a Spanish hospital. RAPD-PCR allowed the identification of six genetic patterns. We also investigated the presence of genes involved in producing adhesins, toxins and the capsule; the biofilm; and antimicrobial resistance. A notable percentage of the isolates carried virulence genes and showed medium-high ability to form biofilms. Next, we assessed the strains' susceptibility to two phages (phiIPLA-C1C and phiIPLA-RODI) and one endolysin (LysRODI). All strains were resistant to phiIPLA-C1C, and most (70.2%) were susceptible to phiIPLA-RODI. Regarding LysRODI, all strains displayed susceptibility, although to varying degrees. There was a correlation between endolysin susceptibility and the random amplification of polymorphic DNA (RAPD) profile or the presence of some virulence genes (fnbA, eta, etb, PVL and czr), but that was not observed with biofilm-forming ability, strain origin or phage sensitivity. Taken together, these findings can help to explain the factors influencing endolysin effectiveness, which will contribute to the development of efficient therapies targeting MRSA infections.

13.
PLoS One ; 15(11): e0241608, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33211741

RESUMO

The poultry red mite (PRM), Dermanyssus gallinae, a potential vector of pathogens to animals and humans, causes impaired bird welfare. A study investigated changes in behavioural variables, physiological biomarkers, and health parameters following acaricidal treatment of PRM infestation of laying hens on a commercial farm. Mite traps determined the challenge to 12,700 hens before and after drinking water administration of the acaricide, fluralaner (Exzolt®, 0.5 mg/kg; Weeks 0 and 1). Weekly daytime direct observations and night-time video recordings monitored bird behaviours from Weeks -6 through +6. Blood samples were collected from randomly-selected birds (Weeks -6, -1, and +6). Following treatment, mite count reductions (>99%) were statistically significant (P < 0.0001), as were night-time reductions in the percent of hens showing activity, preening, head scratching (all P < 0.0001), and head shaking (P = 0.0007). Significant daytime reductions were observed in preening and head scratching (both P < 0.0001), head shaking (P = 0.0389), severe feather pecking (P = 0.0002), and aggressive behaviour (P = 0.0165). Post-treatment, comb wounds were significantly reduced (P = 0.0127), and comb colour was significantly improved (P < 0.0001). Heterophil/lymphocyte ratio was significantly reduced at Weeks 1 and 6 (P = 0.0009 and P < 0.0001, respectively). At Week 6, blood corticosterone (P = 0.0041) and total oxidant status (P < 0.0001) were significantly reduced, and haemoglobin and mean corpuscular haemoglobin significantly increased (P < 0.0001). Farm production records indicated that those post-treatment improvements were accompanied by significant reductions in weekly mortality rate (P = 0.0169), and significant recovery in mean weekly egg weights (P < 0.0001) and laying rate (P < 0.0001). The improvements in behavioural variables, physiological biomarkers, and health parameters that were observed following the elimination of PRM on a commercial farm indicate that infestations can be a cause of reduced hen welfare.


Assuntos
Acaricidas/sangue , Isoxazóis/sangue , Doenças das Aves Domésticas/tratamento farmacológico , Aves Domésticas/parasitologia , Ácaros e Carrapatos/efeitos dos fármacos , Ácaros e Carrapatos/patogenicidade , Acaricidas/administração & dosagem , Acaricidas/farmacologia , Acaricidas/uso terapêutico , Animais , Comportamento Animal , Feminino , Hemoglobinas/análise , Isoxazóis/administração & dosagem , Isoxazóis/farmacologia , Isoxazóis/uso terapêutico , Contagem de Linfócitos , Reprodução/efeitos dos fármacos
14.
Neotrop Entomol ; 48(4): 706-716, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30941675

RESUMO

Aedes aegypti (Linnaeus) (Diptera: Culicidae) is the main vector of viruses causing dengue, chikungunya, Zika, and yellow fever, worldwide. This report focuses on immuno-blocking four critical proteins in the female mosquito when fed on blood containing antibodies against ferritin, transferrin, one amino acid transporter (NAAT1), and acetylcholinesterase (AchE). Peptides from these proteins were selected, synthetized, conjugated to carrier proteins, and used as antigens to immunize New Zealand rabbits. After rabbits were immunized, a minimum of 20 female mosquitos were fed on each rabbit, per replicate. No effect in their viability was observed after blood-feeding; however, the number of infertile females was 20% higher than the control when fed on AchE-immunized rabbits. The oviposition period was significantly longer in females fed on immunized rabbits than those fed on control (non-immunized) rabbits. Fecundity (eggs/female) of treated mosquitoes was significantly reduced (about 50%) in all four treatments, as compared with the control. Fertility (hatched larvae) was also significantly reduced in all four treatments, as compared with the control, being the effect on AchE and transferrin the highest, by reducing hatching between 70 and 80%. Survival to the adult stage of the hatched larvae showed no significant effect, as more than 95% survival was observed in all treatments, including the control. In conclusion, immuno-blocking of these four proteins caused detrimental effects on the mosquito reproduction, being the effect on AchE the most significant.


Assuntos
Acetilcolinesterase/imunologia , Aedes/fisiologia , Anticorpos/imunologia , Imunização/veterinária , Proteínas de Insetos/imunologia , Sistemas de Transporte de Aminoácidos/imunologia , Animais , Feminino , Ferritinas/imunologia , Fertilidade , Hemolinfa , Imunoglobulina G/imunologia , Mosquitos Vetores/fisiologia , Oviposição , Coelhos , Reprodução , Transferrina/imunologia
15.
Bol. latinoam. Caribe plantas med. aromát ; 23(2): 257-272, mar. 2024. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1552388

RESUMO

The use and knowledge of native and naturalized medicinal plants were evaluated in four communities of Villa Corzo, Chiapas, Mexico. The information was obtained through semi - structured surveys conducted with 1 18 people of different age and gender categories. To determine the most important plant species, indexes of value and frequency of use were generated. Seventy - nine species of 49 families were recorded, as well as their use in the treatment of various disea ses according to local knowledge. The species with the highest value of use were Aloe vera (L.) Burm. f., Verbena officinalis L. (verbena), Ocimum basilicum L. (basil) and Psidium guajava L. (guava). (guava). The most important families by number of specie s used were, in order of importance: Asteraceae and Rutaceae with five species Lamiaceae, Fabaceae and Rosaceae with four species each.


Se evaluaron el uso y conocimiento de las plantas medicinales nativas y naturalizadas en cuatro comunidades de Villa Corzo, Chiapas, México. La información se obtuvo a través de encuestas semiestructuradas realizadas a 118 personas de distintas categorías de edad y género. Para determinar las especies de plantas más importantes se generaron índices de valor y frecuencia de uso. Se registraron 79 especies de 49 familias, así como su uso en el tratamiento de diversas enfermedades de acuerdo al conocimiento local. Las especies con mayor valor de uso fueron Aloe vera (L.) Burm. f. (sábila), Verbena officinalis L. (verbena), Ocimum basilicum L. (albahaca) y Psidium guajava L. (guayaba). Las familias más importantes por el número de especies utilizadas fueron, en orden de importancia: Asteraceae y Rutaceae con cinco especies, Lamiaceae, Fabaceae y Rosaceae con cuatro especies cada una.


Assuntos
Plantas Medicinais/química , Extratos Vegetais/farmacologia , Etnofarmacologia , Extratos Vegetais/química , Inquéritos e Questionários , Conhecimento , México
16.
Animals (Basel) ; 8(7)2018 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-29976913

RESUMO

There is a lack of protocols specifically developed for the assessment of welfare of wild animals in captivity, even when it is known that providing good standards of welfare is important. The aim of this study was the development and the application of a protocol for the assessment of welfare in captive dorcas gazelles. The protocol was mainly developed taking into account the protocol for the assessment of welfare in cattle from the Welfare Quality® project, the available literature of the biology of this species and the Husbandry Guidelines developed for captive breeding and management of this species. The protocol was specifically developed for dorcas gazelles and included four principles, 10 criteria and 23 animal and environmental-based indicators. To test its utility, this protocol was applied to five different groups of gazelles from three different zoos. Its application made possible to detect areas for improvement in all groups assessed.

17.
Front Plant Sci ; 6: 77, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25755658

RESUMO

Fungi belonging to the genus Trichoderma, commonly found in soil or colonizing plant roots, exert beneficial effects on plants, including the promotion of growth and the induction of resistance to disease. T. virens and T. atroviride secrete the proteins Sm1 and Epl1, respectively, which elicit local and systemic disease resistance in plants. In this work, we show that these fungi promote growth in tomato (Solanum lycopersicum) plants. T. virens was more effective than T. atroviride in promoting biomass gain, and both fungi were capable of inducing systemic protection in tomato against Alternaria solani, Botrytis cinerea, and Pseudomonas syringae pv. tomato (Pst DC3000). Deletion (KO) of epl1 in T. atroviride resulted in diminished systemic protection against A. solani and B. cinerea, whereas the T. virens sm1 KO strain was less effective in protecting tomato against Pst DC3000 and B. cinerea. Importantly, overexpression (OE) of epl1 and sm1 led to an increase in disease resistance against all tested pathogens. Although the Trichoderma WT strains induced both systemic acquired resistance (SAR)- and induced systemic resistance (ISR)-related genes in tomato, inoculation of plants with OE and KO strains revealed that Epl1 and Sm1 play a minor role in the induction of these genes. However, we found that Epl1 and Sm1 induce the expression of a peroxidase and an α-dioxygenase encoding genes, respectively, which could be important for tomato protection by Trichoderma spp. Altogether, these observations indicate that colonization by beneficial and/or infection by pathogenic microorganisms dictates many of the outcomes in plants, which are more complex than previously thought.

18.
J Microbiol Biotechnol ; 21(7): 686-96, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21791954

RESUMO

To deal with pathogens, plants have evolved sophisticated mechanisms including constitutive and induced defense mechanisms. Phytohormones play important roles in plant growth and development, as well as in the systemic response induced by beneficial and pathogen microorganisms. In this work, we identified an Aspergillus ustus isolate that promotes growth and induces developmental changes in Solanum tuberosum and Arabidopsis thaliana. A. ustus inoculation on A. thaliana and S. tuberosum roots induced an increase in shoot and root growth, and lateral root and root hair numbers. Assays performed on Arabidopsis lines to measure reporter gene expression of auxin-induced/ repressed or cell cycle controlled genes (DR5 and CycB1, respectively) showed enhanced GUS activity, when compared with mock-inoculated seedlings. To determine the contribution of phytohormone signaling pathways in the effect elicited by A. ustus, we evaluated the response of a collection of hormone mutants of Arabidopsis defective in auxin, ethylene, cytokinin, or abscisic acid signaling to the inoculation with this fungus. All mutant lines inoculated with A. ustus showed increased biomass production, suggesting that these genes are not required to respond to this fungus. Moreover, we demonstrated that A. ustus synthesizes auxins and gibberellins in liquid cultures. In addition, A. ustus induced systemic resistance against the necrotrophic fungus Botrytis cinerea and the hemibiotrophic bacterium Pseudomonas syringae DC3000, probably through the induction of the expression of salicylic acid, jasmonic acid/ethylene, and camalexin defense-related genes in Arabidopsis.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/microbiologia , Aspergillus/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Arabidopsis/imunologia , Botrytis/patogenicidade , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Brotos de Planta/crescimento & desenvolvimento , Pseudomonas syringae/patogenicidade , Transdução de Sinais , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/imunologia , Solanum tuberosum/microbiologia
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