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Current-induced spin-orbit torques (SOTs) are of interest for fast and energy-efficient manipulation of magnetic order in spintronic devices. To be deterministic, however, switching of perpendicularly magnetized materials by SOT requires a mechanism for in-plane symmetry breaking. Existing methods to do so involve the application of an in-plane bias magnetic field, or incorporation of in-plane structural asymmetry in the device, both of which can be difficult to implement in practical applications. Here, we report bias-field-free SOT switching in a single perpendicular CoTb layer with an engineered vertical composition gradient. The vertical structural inversion asymmetry induces strong intrinsic SOTs and a gradient-driven Dzyaloshinskii–Moriya interaction (g-DMI), which breaks the in-plane symmetry during the switching process. Micromagnetic simulations are in agreement with experimental results, and elucidate the role of g-DMI in the deterministic switching processes. This bias-field-free switching scheme for perpendicular ferrimagnets with g-DMI provides a strategy for efficient and compact SOT device design., Switching of ferrimagnets by current-induced spin-orbit torque is promising for spintronics, due to their high-speed dynamics and small macroscopic magnetization. Switching of perpendicularly magnetized materials, however, requires a bias field for symmetry breaking. Here, Zheng et al demonstrate field-free current-induced switching of perpendicular ferrimagnets, using a compositional gradient-driven Dzyaloshinskii–Moriya interaction.

A new species of oak gall wasp, Cynips baskalei sp. n. (Cynipidae: Cynipini), was de- scribed from Turkey. Only asexual females of the species are known and induce galls on leaves of Quercus macranthera Fisch. & Mey. ex Hohen., Quercus petraea (Matt.) Liebl. and Quercus pubescens Willd. SEM images, data on the diagnosis, distribution, and biology of the new species were provided in this study. http://www.zoobank.org/urn:lsid:zoobank.org:pub:4F3C1A11-E703-4B3C-A5E8-D86FEEF442CB. © 2020 Informa UK Limited, trading as Taylor & Francis Group.

We propose an analysis method that extracts trial-reproducible (i.e., recurring) event-related spatiotemporal EEG patterns by optimizing a spatial filter as well as trial timings of task-related components in the time domain simultaneously in a unified manner. Event-related responses are broadly categorized into evoked and induced responses, but those are analyzed commonly in the time and the time-frequency domain, respectively. To facilitate a comparison of evoked and induced responses, a unified method for analyzing both evoked and induced responses is desired. Here we propose a method of cross-correlation task-related component analysis (xTRCA) as an extension of our previous method. xTRCA constructs a linear spatial filter and then optimizes trial timings of single trials based on trial reproducibility as an objective function. The spatial filter enhances event-related responses, and the temporal optimization compensates trial-by-trial latencies that are inherent to ERPs. We first applied xTRCA to synthetic data of induced responses whose phases varied from trial to trial, and found that xTRCA could realign the induced responses by compensating the phase differences. We then demonstrated with mismatch negativity data that xTRCA enhanced the event-related-potential waveform observed at a single channel. Finally, a classification accuracy was improved when trial timings were optimized by xTRCA, suggesting a practical application of the method for a brain computer interface. We conclude that xTRCA provides a unified framework to analyze and enhance event-related evoked and induced responses in the time domain by objectively maximizing trial reproducibility.

Orientador: Jose Roberto Trigo Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia Resumo: A produção de defesas contra a herbivoria é essencial para o sucesso reprodutivo das plantas, no entanto pode ser custosa. Esses custos resultam da redução de investimento em outras partes do metabolismo, como o crescimento e a reprodução. Nesse estudo, usamos Asclepias curassavica (Apocynaceae: Asclepiadoideae) como modelo para avaliar como uma planta divide seus recursos entre crescimento, reprodução e defesas. A. curassavica é uma planta anual que possui cardenolidas como defesas. Para verificar como esta responde a herbivoria, simulamos a mesma através de dano artificial (DA) e medimos crescimento (biomassa de folhas e raízes) e reprodução (número de flores, frutos e sementes e biomassa de sementes) em um experimento em longo prazo. Em um experimento em curto prazo, medimos a produção de defesas (concentração de cardenolidas), para avaliar se estas podem estar interferindo no crescimento e reprodução desta espécie. Correlacionamos também, em uma população natural, a concentração de cardenolidas com a percentagem de herbivoria foliar. O hormônio jasmonato de metila (JM) é usado para induzir compostos do metabolismo secundário em plantas, sem o custo adicional da remoção de tecido fotossinteticamente ativo causada por dano artificial ou natural. Usamos esse composto em ambos os desenhos experimentais acima ao invés de remoção da área foliar para avaliar se havia indução de cardenolidas e seu efeito sobre o crescimento e reprodução de A. curassavica. Nossos resultados demonstraram uma redução significativa do número total de frutos, sementes e da massa final de raízes em plantas com tratamento de DA em longo prazo. O crescimento do tratamento DA não diferiu do controle, sugerindo crescimento compensatório das folhas à custa do investimento em raízes e em reprodução. Os custos reprodutivos e de crescimento de raízes detectados no experimento de longo prazo podem resultar da diminuição da capacidade fotossintética em plantas danificadas e investimento simultâneo em crescimento compensatório das folhas. No experimento de curto prazo, não houve alteração da razão de indução de cardenolidas sugerindo que o dano artificial não induz defesas nessa espécie. A ausência de correlação entre cardenolidas e porcentagem de dano natural em plantas coletadas em campo pode sugerir dois cenários excludentes: 1. a indução de cardenolidas não seria importante para a defesa de A. curassavica, ou 2. a ausência de correlação, associada a baixa percentagem de herbivoria implicaria em uma defesa constitutiva eficaz contra herbívoros. O tratamento com JM a longo prazo também mostrou uma tendência à redução do crescimento de raízes e redução significativa da biomassa e porcentagem de germinação de sementes. Nas plantas tratadas com JM a curto prazo, houve um aumento significativo de cardenolidas tardio (384 h após tratamento) sugerindo que estas podem contribuir para a redução de aptidão observada no experimento de longo prazo e que existem custos da produção das mesmas. Dano artificial leva à diminuição da aptidão, através de desvio de investimento em raízes para o crescimento compensatório das folhas. No caso do jasmonato, não houve perda de massa fotossinteticamente ativa (folhas) e a redução do crescimento de raízes pode ser resultado de um efeito direto do tratamento de JM ou indireto causado pela indução de outras partes do metabolismo (p.ex. metabolismo secundário) causada por esse fitohormônio. Experimentos futuros devem comparar os presentes resultados com dano real por um dos herbívoros especialistas para avaliar a eficácia do dano artificial em induzir cardenolidas e o papel dessa indução sobre outras partes do metabolismo da mesma Abstract: Although the investment in defensive traits against herbivory is essential to the reproductive success of plants, it may be costly. These costs result from reduced investment in other metabolic functions such as growth and reproduction. In the present study, we used the milkweed Asclepias curassavica (Apocynaceae: Asclepiadoideae) as a model to study how a plant divides its resources between growth, reproduction and defense. A. curassavica is an annual weed that uses cardenolides as defenses against herbivory. To evaluate how Asclepias curassavica responds to herbivores, we simulated herbivory by artificial damage (AD) and measured growth (leaf and root biomass) and reproduction (number of flowers, fruit and seeds and seed biomass) in a long term experiment. We also measured defensive traits (cardenolide concentration) in a short term experiment to verify whether there is an investment in defense that may interfere with growth and reproduction. We also correlated cardenolide concentration in a natural population with percent leaf damage. As the plant hormone, methyl jasmonate (MJ) is commonly used to induce secondary metabolism in plants without the additional costs of tissue removal, we used this compound in the same experimental designs instead of AD. Our results from the long term AD treatment showed a significant decrease in final root biomass and in total fruit set and seed number. Plants from the AD treatment did not differ from controls in leaf growth, suggesting that there was a compensatory growth in the former at the expense of root growth. The reproductive and growth costs detected in this experiment may result from reduced photosynthetic capacity in damaged plants and concomitant compensatory leaf growth. In the short term, we found no induction of cardenolides compared to controls, suggesting that artificial damage does not induce defenses. The lack of correlation between cardenolides and percentage leaf damage in plants collected from a natural population suggest two self-excluding scenarios: 1. the induction of cardenolides is not important for the defense of A. curassavica, or 2. the lack of correlation, coupled with low herbivore damage, suggests that this plant has an efficient constitutive defense against herbivores. The long term MJ treatment showed a trend in reduced root biomass and significantly reduced seed biomass and percentage germination. In the short term MJ treatment we found a significant increase in cardenolide concentration (after 384 h) suggesting that the production of these defenses is costly and this may have contributed to observed costs in the long term experiment. Apparently, the artificial damage treatment leads to reduced fitness through reduced root growth which is a consequence of compensatory leaf growth. In the methyl jasmonate treatment, there was no removal of photosythetically active tissue (leaves) and the reduced root growth may be a direct effect of this phytohormone or an indirect effect caused by the induction of other metabolic pathways (such as secondary metabolism) caused by this hormone. Future experiments should compare the present results with natural damage by specialist herbivores to evaluate the efficiency of artificial damage in inducing cardenolides and the role of the induction of these substances on other metabolic functions Mestrado Mestre em Ecologia

BACKGROUND AND OBJECTIVES: The eutrophication process is increased by anthropogenic or aquaculture facilites in marine ecosystems. DNA damage biomarkers for fish species detect genotoxic parameters for ecological risk assessment. The aim of the present study was to determine genotoxic potential induced by marine cage culture in Iskenderun Bay on gilthead sea bream (Sparus aurata) using Comet assay. METHODS: This study was conducted at cage and reference stations of Iskenderun Bay, Northeastern Mediterranean in January 2017. The wild and cultured samples of S. aurata and water samples were collected from wild and fish farm. FINDINGS: The DNA damages at gill and liver cells of gilthead sea bream in the present study were observed with a higher level of DNA damage in gill cells compared to liver cells, and were determined at the low and minimal scale at the cage and reference stations, respectively. The present study demonstrated that the TP values were recorded at 0.020 and 0.016 mg/L in the cage and reference stations which are at border and below 0.020 mg/L. The DIN values were recorded at 0.097 and 0.075 mg/L in the cage and reference stations, which are at below 0.1 mg/L. The water bodies in the cage and reference stations exhibit Moderate/Mesotrophic water quality The correlations between physical-chemical parameters and DNA damage were shown that DIN, NH4-N, NO3-N and NO2-N in water revealed significant positive correlations with DNA damage levels in gill cells. CONCLUSION: The present study provides the first data set on genotoxic damage induced by marine cage culture in Iskenderun Bay on gilthead sea bream. The result of this research is an early warning for the marine system and further detailed research is needed to establish the source of the pollution and monitor environmental polluton.

BACKGROUND AND OBJECTIVES: The eutrophication process is increased by anthropogenic or aquaculture facilities in marine ecosystems. DNA damage biomarkers for fish species detect genotoxic parameters for ecological risk assessment. The aim of the present study was to determine genotoxic potential induced by marine cage culture in Iskenderun Bay on gilthead sea bream (Sparus aurata) using Comet assay. METHODS: This study was conducted at cage and reference stations of Iskenderun Bay, Northeastern Mediterranean in January 2017. The wild and cultured samples of S. aurata and water samples were collected from wild and fish farm. FINDING: The DNA damages at gill and liver cells of gilthead sea bream in the present study were observed with a higher level of DNA damage in gill cells compared to liver cells, and were determined at the low and minimal scale at the cage and reference stations, respectively. The present study demonstrated that the TP values were recorded at 0.020 and 0.016 mg/L in the cage and reference stations which are at border and below 0.020 mg/L. The DIN values were recorded at 0.097 and 0.075 mg/L in the cage and reference stations, which are at below 0.1 mg/L. The water bodies in the cage and reference stations exhibit Moderate/Mesotrophic water quality The correlations between physical-chemical parameters and DNA damage were shown that DIN, NH4-N, NO3-N and NO2-N in water revealed significant positive correlations with DNA damage levels in gill cells. CONCLUSION: The present study provides the first data set on genotoxic damage induced by marine cage culture in Iskenderun Bay on gilthead sea bream. The result of this research is an early warning for the marine system and further detailed research is needed to establish the source of the pollution and monitor environmental pollution.

Constitutive and inducible terpene production is involved in conifer resistance against insects and fungal infestations. To gain knowledge about local defence responses of Norway spruce bark against pathogens and to find potential chemical markers for resistance breeding, we inoculated the stem of 8-year-old Norway spruce (Picea abies) clonal trees with both Endoconidiophora polonica (Ep, a common fungal pathogen associated with the spruce bark beetle Ips typographus) and Heterobasidion parviporum (Hp, a severe pathogen causing root and stem rot disease). Three weeks after inoculation, the fungal-inoculated and intact bark from each tree was sampled. The terpenes in tree bark were extracted with hexane and characterized by gas chromatography–mass spectrometry (GC-MS). The two fungi induced varied terpene responses in the four spruce clones used. Three of the clones showed a 2.3-fold to 5.7-fold stronger terpene response to Hp relative to Ep inoculation, while one clone responded similarly to inoculation with the two fungal pathogens. The amount of the diterpenes thunbergol and geranyllinalool varied between the clones. The level of thunbergol was higher in both intact and fungal-inoculated bark from the less susceptible clones compared with the more susceptible clones. Geranyllinalool was present in higher amounts in the susceptible clones and is thus a possible marker for susceptibility. Our observations show that Norway spruce employs a similar chemical mechanism against the two fungal pathogens. Based on the present and earlier published data, we suggest that certain Norway spruce genotypes have a strong defence reaction against these two pathogens. The diterpenes thunbergol and geranyllinalool might be useful markers of susceptibility in tree-breeding programmes and should be the focus of further detailed investigations.

Common bean (Phaseolus vulgaris L.) is a major legume and is frequently attacked by fungal pathogens, including Fusarium solani f. sp. phaseoli (FSP), which cause Fusarium root rot. FSP substantially reduces common bean yields across the world, including China, but little is known about how common bean plants defend themselves against this fungal pathogen. In the current study, we combined next-generation RNA sequencing and metabolomics techniques to investigate the changes in gene expression and metabolomic processes in common bean infected with FSP. There were 29,722 differentially regulated genes and 300 differentially regulated metabolites between control and infected plants. The combined omics approach revealed that FSP is perceived by PAMP-triggered immunity and effector-triggered immunity. Infected seedlings showed that common bean responded by cell wall modification, ROS generation, and a synergistic hormone-driven defense response. Further analysis showed that FSP induced energy metabolism, nitrogen mobilization, accumulation of sugars, and arginine and proline metabolism. Importantly, metabolic pathways were most significantly enriched, which resulted in increased levels of metabolites that were involved in the plant defense response. A correspondence between the transcript pattern and metabolite profile was observed in the discussed pathways. The combined omics approach enhances our understanding of the less explored pathosystem and will provide clues for the development of common bean cultivars&rsquo, resistant to FSP.

Pests and pathogens are a major concern in eucalypts in native forests and plantations, as they cause loss of biodiversity and productivity and reduce tree survival. Pest and pathogen management requires multiple strategies to minimise impacts and maximise forest health, involving silvicultural practices, use of pesticides, biocontrol and selection of resistant genotypes through breeding programs. Greater knowledge of host interactions with pests and pathogens and consequences for plant performance and physiology may contribute significantly to the development of pest and disease management strategies., This thesis focuses on plant interactions with pests and pathogens and understanding plant physical and chemical parameters in response to damage. The research included controlled and field experiments with Corymbia spp. and hybrids, ecologically and economically important eucalypt taxa. The research investigated, (1) Corymbia citriodora subsp. variegata chemical and physical response to insect damage, (2) Differences in physical and chemical foliar parameters between C. citriodora subsp. variegata plants resistant and susceptible to Quambalaria pitereka and Austropuccinia psidii, (3) Comparison between C. citriodora subsp. variegata response to Q. pitereka and A. psidii infection, (4) The levels of susceptibility of Corymbia species and hybrids to pests and pathogens in the field and the consequences of damage on plant performance, The three controlled experiments were conducted in a shadehouse to examine specific plant responses to pest and pathogen damage, involving analyses of plant growth rate, leaf anatomy and leaf chemistry. In the first experiment, seedlings of C. citriodora subsp. variegata were subjected to Paropsis atomaria larval feeding, mechanical wounding and no damage (control), to examine the effect of leaf tissue removal on the growth rate, leaf toughness, leaf trichome density and leaf secondary metabolites. Plant response was analysed in damaged leaves (local response), undamaged leaves in damaged plants (systemic response), and in new leaves produced post-treatment (delayed response). Plants did not exhibit a local chemical response, nor differences in growth rate or measured leaf physical parameters following damage. There was, however, a systemic chemical response to P. atomaria larval feeding and mechanical wounding, with plants subjected to larval feeding also exhibiting a delayed chemical response. Six compound classes were identified, of these, long-chain hydrocarbons were lower in the treatments relative to undamaged plants, whereas the proportion of monounsaturated hydrocarbons and monoterpenes was higher. When analysed across compound classes, larval mortality was significantly correlated with monounsaturated hydrocarbons and long-chain hydrocarbons. The potential mechanisms underlying the observed responses are discussed., The second shadehouse trial examined plant-pathogen interactions. Corymbia citriodora subsp. variegata seedlings from different provenances were inoculated with either Q. pitereka or A. psidii, and resistance classes for the two pathogens were determined. Differential plant responses between severely infected (susceptible) and resistant plants (low levels of damage) for each pathogen were quantified. Growth rate, leaf toughness and leaf secondary metabolites were compared between uninoculated (control), resistant and susceptible plants for both pathogens. Post-treatment leaf samples were taken when plants were free of disease, to determine if secondary metabolite profiles would assist in susceptibility prediction. Susceptible plants infected by Q. pitereka had greater leaf toughness while those infected by A. psidii had reduced plant growth and changes in the expression of secondary metabolites in comparison to uninoculated controls and resistant plants. The plants severely damaged by A. psidii exhibited a reduction in the proportion of monoterpenes and monounsaturated hydrocarbons and an increased proportion of long chain hydrocarbons. Post-treatment samples did not differ from each other or control plants, suggesting secondary metabolites are not a good predictor of susceptibility to these pathogens in C. citriodora subsp. variegata. The potential mechanisms underlying the observed responses are discussed and contrasted with similar studies in other species., The third shadehouse trial involved seedlings of C. citriodora subsp. variegata from Woondum (26° 25' S, 152° 81' E), assome families from this provenance may display resistance to Q. pitereka and susceptibility to A. psidii. . Quambalaria pitereka innoculated plants, A. psidii inoculated plants and uninoculated control plants were assessed to compare phenotypical responses including growth rate, leaf toughness, leaf thickness, leaf chemistry and leaf histochemistry. Only A. psidii infection resulted in alteration of leaf toughness and leaf chemistry in comparison to Q. pitereka infection and controls. The histochemical analyses suggest that both pathogens alter the distribution of polyphenols and tannins in comparison to control plants. Further discussion underlying the differences between infections by these pathogens are explored., The field experiment studied four pure taxa – C. citriodora subsp. citriodora, C. citriodora subsp. variegata, C. henryi and C. torelliana – and three hybrids – C. torelliana × C. citriodora subsp. citriodora, C. torelliana × C. citriodora subsp. variegata and C. torelliana × C. henryi. The aim of the field trial was to examine tree performance, leaf ontogeny and susceptibility to pests and pathogens over time, through a series of assessments conducted over 24 months. Throughout the experiment, plants were naturally affected by several generalist insect defoliators, and Q. pitereka, an endemic pathogen of Corymbia spp. that causes necrosis, leaf distortion, and affects plant performance and survival. Results indicated significant variations between taxa and across time for all assessed parameters and significant taxon × time interactions. The characteristics of each taxon and the influence of environmental conditions underlying the studied parameters of tree performance and pest and disease susceptibility are discussed., These results reveal the effects of damage on tree performance, the variable susceptibility to pests and pathogens between Corymbia species and hybrids, and suggest mechanisms underlying leaf physical and chemical responses observed in C. citriodora subsp. variegata under pest and pathogen damage. The knowledge generated in this thesis benefits the development of pest and disease management, contributes to strategies to select resistant genotypes and adds a relevant understanding on plant responses and interactions with pests and pathogens in natural and controlled conditions.

Common bean (Phaseolus vulgaris L.) is a major legume and is frequently attacked by fungal pathogens, including Fusarium solani f. sp. phaseoli (FSP), which cause Fusarium root rot. FSP substantially reduces common bean yields across the world, including China, but little is known about how common bean plants defend themselves against this fungal pathogen. In the current study, we combined next-generation RNA sequencing and metabolomics techniques to investigate the changes in gene expression and metabolomic processes in common bean infected with FSP. There were 29,722 differentially regulated genes and 300 differentially regulated metabolites between control and infected plants. The combined omics approach revealed that FSP is perceived by PAMP-triggered immunity and effector-triggered immunity. Infected seedlings showed that common bean responded by cell wall modification, ROS generation, and a synergistic hormone-driven defense response. Further analysis showed that FSP induced energy metabolism, nitrogen mobilization, accumulation of sugars, and arginine and proline metabolism. Importantly, metabolic pathways were most significantly enriched, which resulted in increased levels of metabolites that were involved in the plant defense response. A correspondence between the transcript pattern and metabolite profile was observed in the discussed pathways. The combined omics approach enhances our understanding of the less explored pathosystem and will provide clues for the development of common bean cultivars’ resistant to FSP.

Plant–insect interactions typically take place in complex settings of interactions among multiple trophic levels as well as multiple species in each trophic level. The complex interaction network may strongly impact on extrapolations of resistance traits to have a defensive function. For example, the induced response plants express to their current attacker often enhances resistance to that attacker, but may make a plant more susceptible to attack by another herbivore. Hence, the defensive function or plant fitness benefit of the response to a single attacker may be misinterpreted from pairwise interactions. Moreover, plant physiological responses to a first stress by herbivory may hamper the response to a second stress and lead to conclusions of maladaptation in plant defence responses. In light of the entire community of attackers and beneficial organisms the plant interacts with, the susceptibility to some attackers may be a consequence of adaptations that reduce fitness costs of herbivory when considering the full sweep of species that affect plant fitness. A similar argumentation may apply for indirect resistance in which predators or parasitoids dampen the effect of herbivores on plants. Plant volatiles that attract third trophic level organisms such as parasitoids may at the same time attract enemies of the parasitoids in the fourth trophic level, hyperparasitoids, which again dampen the effect of parasitoids on herbivores. In addition, the effectiveness of predators and parasitoids may be dependent on habitat complexity. Here, I plea for studies on the full plant-associated community to understand the fitness outcome of an (induced) plant trait and hence coin it induced direct or indirect plant defence.

[Background] Plants can respond to insect attack via defense mechanisms that reduce insect performance. In this study, we examined the effects of several treatments applied to two maize genotypes (one resistant, one susceptible) on the subsequent growth and survival of Sesamia nonagrioides Lef. (Mediterranean corn borer, MCB) larvae. The treatments were infestation with MCB larvae, application of MCB regurgitant upon wounding, wounding alone, or exposure to methyl jasmonate, and they were applied at the V6–V8 stage of maize development. We also monitored changes in the concentrations of compounds known to be involved in constitutive resistance, such as cell wall-bound hydroxycinnamates and benzoxazinoids., [Results] In both maize genotypes, the leaves of plants pre-infested with MCB larvae were less suitable for larval development than those from untreated plants. Application of MCB regurgitant upon wounding, and wounding itself, resulted in leaf tissues becoming less suitable for larval growth than those of pre-infested plants, suggesting that there could be herbivore-associated effector molecules that suppress some wounding responses. A single application of MCB regurgitant did not seem to mimic feeding by MCB larvae, although the results suggested that regurgitant deposited during feeding may have enhanced ferulates and diferulates synthesis in infested vs. control plants. Jasmonic acid may play a role in mediating the maize response to MCB attack, but it did not trigger hydroxycinnamate accumulation in the leaves to a level comparable to that induced by larval leaf feeding. The EP39 maize genotype showed an increase in leaf cell wall strength by increasing hemicellulose cross-linking in response to MCB attack, while induced defenses in the EP42 plants appeared to reflect a broader array of resistance mechanisms., [Conclusions] The results indicated that leaf feeding by MCB larvae can increase leaf antibiosis against MCB in two maize genotypes with contrasting levels of resistance against this borer. Also, the larval regurgitant played a positive role in eliciting a defense response. We determined the effects of the plant response on larval growth, and detected defense compounds related to borer resistance., This research was supported by the National Plan for Research and Development of Spain (AGL2012-33415, AGL2015-67313-C2-1-R, and AGL2015-67313-C2-2-R) co-financed by the European Social Fund (FEDER). R. Santiago acknowledges postdoctoral contract “Ramón y Cajal” financed by the Ministry of Economy and Competitiveness (Spain), Vigo University, and the European Social Fund.

Kaya, Yilmaz/0000-0003-1506-7913; Huyop, Fahrul Zaman/0000-0003-3978-4087; ozturk, murat/0000-0002-9677-3651 WOS: 000390575200002 Efficacy of Pseudomonas putida (CKPp9) was tested under in vitro and in vivo conditions for their ability to plant growth promoting characteristics in tomato seedlings against Clavibacter michiganensis subsp. michiganensis (CmmGo2) infection. A significant difference was observed between bacterized tomato seedlings with P. putida (CKPp9) and the other treatments (P < 0.01). Also, CmmGo2 was detected significant difference the least plant growth parameters for tomato seedlings (P < 0.01). To correlate the induction of phenolic compounds by the CKPp9 with disease resistance, qualitative and quantitative modifications of phenolic compounds in tomato seedlings were observed in different treatments. High performance liquid chromatographic (HPLC) analysis of the leaves of the CKPp9-treated, CmmGo2-treated, and non-treated (control) plants showed the presence of chlorogenic acid, caffeic acid, catechin and rutin with varied amounts in the CKPp9 treated as well as CmmGo2-treated and non-treated (control) plants. Maximum accumulation of catechin was observed in plants treated with the CKPp9 strain + CmmGo2 strain which was almost 10 times higher than the CKPp9-treated plants and also significantly high when compared to other treatments. A direct relationship between the level of catechin and seedling survivability was observed. P. putida-mediated induction of phenolic compounds as a biochemical barrier in tomato seedlings against C. michiganensis subsp. michiganensis infection is envisaged. (C) 2016 Elsevier Inc. All rights reserved. Ondokuz Mayis University, TurkeyOndokuz Mayis University [PYO. ZRT.1901.14.008] This study was supported by Ondokuz Mayis University, Turkey, Project Management Office with project number of PYO. ZRT.1901.14.008.

Background Rice (Oryza sativa L.), which is a staple food for more than half of the world’s population, is frequently attacked by herbivorous insects, including the rice stem borer, Chilo suppressalis. C. suppressalis substantially reduces rice yields in temperate regions of Asia, but little is known about how rice plants defend themselves against this herbivore at molecular and biochemical level. Results In the current study, we combined next-generation RNA sequencing and metabolomics techniques to investigate the changes in gene expression and in metabolic processes in rice plants that had been continuously fed by C. suppressalis larvae for different durations (0, 24, 48, 72, and 96 h). Furthermore, the data were validated using quantitative real-time PCR. There were 4,729 genes and 151 metabolites differently regulated when rice plants were damaged by C. suppressalis larvae. Further analyses showed that defense-related phytohormones, transcript factors, shikimate-mediated and terpenoid-related secondary metabolism were activated, whereas the growth-related counterparts were suppressed by C. suppressalis feeding. The activated defense was fueled by catabolism of energy storage compounds such as monosaccharides, which meanwhile resulted in the increased levels of metabolites that were involved in rice plant defense response. Comparable analyses showed a correspondence between transcript patterns and metabolite profiles. Conclusion The current findings greatly enhance our understanding of the mechanisms of induced defense response in rice plants against C. suppressalis infestation at molecular and biochemical levels, and will provide clues for development of insect-resistant rice varieties. Electronic supplementary material The online version of this article (doi:10.1186/s12870-016-0946-6) contains supplementary material, which is available to authorized users.

Herbivore damage can induce the host plant to alter the chemical and physical qualities of its leaves, which is thought to be a plant strategy—termed “induced response”—for avoiding further herbivory. In woody plants, many studies have considered variation in induced response with resource availability, but few studies have examined this variation in relation to growth patterns of woody plants. We studied the phenotypic variability of induced response within successively flushing Quercus serrata seedlings. Q. serrata seedlings were grown under controlled conditions. The controlled factors were herbivore damage (herbivore-damaged and -undamaged) and soil fertility (low and high). At each flush stage, the concentrations of condensed tannin (CT), total phenolics (TP), and nitrogen (N) in leaves were analyzed, and the leaf mass per area (LMA) was measured. CT and TP concentrations in leaves and LMA were higher in herbivore-damaged seedlings. Leaves of the first flushes showed greater sensitivity to herbivore damage and had a higher CT concentration than leaves of the later flushes. Furthermore, seedlings growing in low-fertility soil showed a greater induced response. The results suggest that the induced response of Q. serrata seedlings was related to the contributions of the tissue to current productivity. Leaves of the first flush showed a greater induced response, possibly because they play an important role in subsequent growth. The potential of Q. serrata seedlings to adjust the properties of leaves depending on herbivory and soil fertility in relation to growth patterns may be advantageous on the forest floor, where seedlings grow in soil of heterogeneous fertility and are constantly exposed to herbivory.

Heterobasidion parviporum (Hp) were investigated using four clones of Norway spruce (Picea abies) with different susceptibility to Heterobasidion sp. Eight year old trees were inoculated with Ep and Hp to minimize the variation due to environment. After three weeks the bark tissue at the upper border of the inoculation hole were extracted with hexane and analyzed by GC-MS. Both treatment and clonal differences were found based on induced mono-, sesqui- and diterpenes. In addition, the Hp produced toxin, fomanoxin, was identified in lowest amount in the most Hp susceptible clone. The clonal trees seem to use different defense strategies towards the two fungi. One of the clones was able to induce strong chemical defense against both fungi, one clone induced chemical defense only against Ep and the most susceptible clone exhibited the least capacity to produce an effective defense against Ep and Hp. Two diterpenes were found to be distinctly different between clones with different susceptibilities, which can be used as chemical indication of Norway spruce resistance against fungi. QC 20160531

Being minute in size, eriophyoid mites can reach places that are small enough to be inaccessible to their predators. The coconut mite, Aceria guerreronis, is a typical example; it finds partial refuge under the perianth of the coconut fruit. However, some predators can move under the perianth of the coconut fruits and attack the coconut mite. In Sri Lanka, the phytoseiid mite Neoseiulus baraki, is the most common predatory mite found in association with the coconut mite. The cross-diameter of this predatory mite is c. 3 times larger than that of the coconut mite. Nevertheless, taking this predator's flat body and elongated idiosoma into account, it is--relative to many other phytoseiid mites--better able to reach the narrow space under the perianth of infested coconut fruits. On uninfested coconut fruits, however, they are hardly ever observed under the perianth. Prompted by earlier work on the accessibility of tulip bulbs to another eriophyoid mite and its predators, we hypothesized that the structure of the coconut fruit perianth is changed in response to damage by eriophyoid mites and as a result predatory mites are better able to enter under the perianth of infested coconut fruits. This was tested in an experiment where we measured the gap between the rim of the perianth and the coconut fruit surface in three cultivars ('Sri Lanka Tall', 'Sri Lanka Dwarf Green' and 'Sri Lanka Dwarf Green x Sri Lanka Tall' hybrid) that are cultivated extensively in Sri Lanka. It was found that the perianth-fruit gap in uninfested coconut fruits was significantly different between cultivars: the cultivar 'Sri Lanka Dwarf Green' with its smaller and more elongated coconut fruits had a larger perianth-fruit gap. In the uninfested coconut fruits this gap was large enough for the coconut mite to creep under the perianth, yet too small for its predator N. baraki. However, when the coconut fruits were infested by coconut mites, the perianth-rim-fruit gap was not different among cultivars and had increased to such an extent that the space under the perianth became accessible to the predatory mites.

Physical, nutritional and allelochemical reactions generally occur in plant leaves in response to herbivory, and such responses can reduce to a certain extent, the performance and/or preference of subsequent herbivores. This study gave an additional evidence to the induced defense theory through the simulated herbivory in Schima superba, one of the common dominant trees in subtropical evergreen broadleaf forests, southern China. The results showed that the leaves that were damaged in the beginning of the leaf expansion had higher toughness and concentration of tannins, but lower water content and nitrogen content when compared with the control leaves. As a result, the damaged shoots had lower rates of herbivory but a higher shoot growth rate than control shoots. The results may imply that early-season herbivory on the leaves of S. superba reduced the nutritional quality of leaves andincreased the amount of secondary compounds, therefore influencing later-season herbivory through the induction of plant responses that may act to reduce plant quality as food for herbivores. Keywords: Induced response, herbivory, early-season damage, nitrogen content, Schima superba

A produção integrada é um sistema agrícola que objetiva produzir alimentos de boa qualidade de acordo com os requerimentos de sustentabilidade ambiental, segurança alimentar e viabilidade econômica. Apesar de ainda não existirem projetos de produção integrada de morango, técnicas de controle biológico e de resposta induzida a herbivoria poderiam ser utilizadas no controle de ácaros fitófagos do morangueiro. Nesta revisão, serão discutidas estas técnicas de manejo de ácaros dentro do contexto da produção integrada de morango.Integrated production is an agricultural system that aims to produce good quality food, in conformity with the requirements of ambient sustainability, alimentary security and economic viability. Although there is not yet a developed integrated system for strawberry production, techniques based on biological control and induced responses to herbivory could be used to control phytophagous mites on strawberry. In this review we discuss these techniques within an integrated production context on strawberry.

When plants receive volatiles from a damaged plant, the receivers become more resistant to herbivory. This phenomenon has been reported in many plant species and called plant-plant communication. Lab experiments have suggested that several compounds may be functioning as airborne signals. The objective of this study is to identify potential airborne signals used in communication between sagebrush (Artemisia tridentata) individuals in the field. We collected volatiles of one branch from each of 99 sagebrush individual plants. Eighteen different volatiles were detected by GC-MS analysis. Among these, 4 compounds; 1.8-cineol, β-caryophyllene, α-pinene and borneol, were investigated as signals of communication under natural conditions. The branches which received either 1,8-cineol or β-caryophyllene tended to get less damage than controls. These results suggested that 1,8-cineol and β-caryophyllene should be considered further as possible candidates for generalized airborne signals in sagebrush.

Plants may be visited by many species of insects during their life-time. These insects include harmful herbivores above and belowground as well as beneficial natural enemies of herbivores and pollinators. Moreover, these interactions may take place sequentially or simultaneously. Responses of plants in interactions with one species result in phenotypic changes that subsequently affect the performance and behaviour of other species. Plants, thus, mediate interactions among their associated community members and such indirect trait-mediated interactions affect the structure of insect communities. As a consequence, plant-mediated species interactions may also affect plant fitness.

Many metabolomics studies aim to find 'biomarkers': sets of molecules that are consistently elevated or decreased upon experimental manipulation. Biological effects, however, often manifest themselves along a continuum of individual differences between the biological replicates in the experiment. Such differences are overlooked or even diminished by methods in standard use for metabolomics, although they may contain a wealth of information on the experiment. Properly understanding individual differences is crucial for generating knowledge in fields like personalised medicine, evolution and ecology. We propose to use simultaneous component analysis with individual differences constraints (SCA-IND), a data analysis method from psychology that focuses on these differences. This method constructs axes along the natural biochemical differences between biological replicates, comparable to principal components. The model may shed light on changes in the individual differences between experimental groups, but also on whether these differences correspond to, e.g., responders and non-responders or to distinct chemotypes. Moreover, SCA-IND reveals the individuals that respond most to a manipulation and are best suited for further experimentation. The method is illustrated by the analysis of individual differences in the metabolic response of cabbage plants to herbivory. The model reveals individual differences in the response to shoot herbivory, where two 'response chemotypes' may be identified. In the response to root herbivory the model shows that individual plants differ strongly in response dynamics. Thereby SCA-IND provides a hitherto unavailable view on the chemical diversity of the induced plant response, that greatly increases understanding of the system. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11306-012-0414-8) contains supplementary material, which is available to authorized users.

One of the main aims of evolutionary biology is to understand the mechanisms responsible for the phenotypic variation on which natural selection can act. Maternal effects occur when a mother's phenotype or her environment influence her offspring's phenotype. Despite the importance of such effects for the ecology of host-parasite interactions, their role has been relatively neglected to date. In this thesis, we examined how mothers influence the immune defense of their young in an environment that varies in space and time. This work has primarily focused on a colonial seabird, the black-legged kittiwake (Rissa tridactyla). Using this model, we have first shown that specific maternal antibodies against parasites, commonly present in the environment (the bacterium Borrelia burgdorferi s. l. vectored by the seabird tick Ixodes uriae) were transferred from mothers to chicks via the egg yolk. Analyses of observational data in the kittiwake-tick-Borrelia system and an experimental approach using vaccination protocol allowed us to confirm the existence of a maternal effect induced by parasitism and to investigate its potential adaptive properties (immunomodulator effects). Moreover, a study examining the influence of individual factors on this transfer underlined the importance of considering the immunological history of individual and their intrinsic quality in these processes. Finally, our work has stressed the influence of local environmental factors on the general development of immune defenses. Overall, this thesis underlines the importance of maternal effects and the maternal environment in the ecology and evolution of host-parasite interactions and, in turn, suggests a role for such process in the epidemiology of infectious diseases., Un des principaux objectifs de la biologie évolutive est de comprendre les mécanismes responsables de la variation phénotypique sur laquelle la sélection naturelle peut agir. On parle d'effets maternels quand le phénotype de la mère, et/ou l'environnement rencontré par celle-ci, affectent le phénotype de sa descendance. En dépit de l'importance que ces effets sont susceptibles d'avoir pour l'écologie des interactions hôte-parasite, leur rôle a été relativement peu étudié. Dans cette thèse, nous avons examiné la façon dont les mères pouvaient influencer les défenses immunitaires de leurs juvéniles dans un environnement variable dans le temps et dans l'espace. Les travaux ont été principalement menés chez un oiseau de mer colonial, la mouette tridactyle (Rissa tridactyla). Nous avons tout d'abord mis en évidence le fait que des anticorps maternels spécifiquement dirigés contre un parasite susceptible d'être présent dans l'environnement (la bactérie Borrelia burgdorferi s. l. transmis par la tique Ixodes uriae), étaient transmis de la mère aux poussins via le jaune d'oeuf. L'analyse de données d'observation effectuées sur le système mouette-tique-Borrelia ainsi qu'une approche expérimentale utilisant un vaccin nous ont permis de confirmer l'existence d'un effet maternel induit par le parasitisme et d'évaluer une part de son caractère potentiellement adaptatif (effet immunomodulateur). De plus, une étude menée sur l'effet des caractéristiques individuelles sur le transfert d'anticorps nous a permis de souligner l'importance de considérer l'histoire immunologique des individus dans ce processus. Nos travaux ont enfin montré l'effet de différents facteurs de l'environnement sur le développement global des défenses immunitaires. L'ensemble de ces travaux révèle l'importance des effets maternels et de l'environnement maternel dans l'écologie et l'évolution des interactions hôte-parasite, et donc potentiellement dans l'épidémiologie des maladies infectieuses.

Previous work showed that anthocorid predators aggregate around gauze cages containing Psylla-infested trees in a pear orchard. Because anthocorids responded to odor from Psylla-infested leaves in a laboratory test, it was hypothesized that these aggregative responses in the field were triggered by olfaction of compounds associated with Psylla injury. We present chemical analyses of volatiles from damaged and undamaged plants and studies on behavioral responses of anthocorid predators to compounds released by damaged plants. Leaf headspace volatiles from clean and Psylla-infested pear trees were collected on Tenax and identified by GC-MS after thermodesorption. Twelve volatiles were found exclusively in headspace samples from Psylla-infested leaves. Six were present in significantly higher quantities in samples from infested leaves: the monoterpene, (E,E)-?-farnesene, the phenolic, methyl salicylate, and the green leaf compounds, (Z)-3-hexen-1-yl acetate, (Z)-3-hexen-1-ol, 1-hexyl-acetate, and 1-penten-3-ol. These compounds are known to be produced by plants, and damage by pear psyllids seems to trigger their emission. Blend composition varied and was partly correlated with tree or leaf age and degree of Psylla infestation. To study whether compounds associated with leaf injury elicit olfactory responses in anthocorid predators, apple-extracted (E,E)-?-farnesene, synthetic methyl salicylate, and (Z)-3-hexen-1-yl acetate were offered in a Y-tube olfactometer to field-collected adult Anthocoris spp. Significant positive responses were found to both the monoterpene and the phenolic, but not to the green leaf volatile. The results lend support to the hypothesis that predator attraction to herbivore-infested pear trees is mediated by herbivory-induced plant volatiles.

In plant-arthropod associations, the first herbivores to colonise a plant may directly or indirectly affect community assembly on that particular plant. Whether the order of arrival of different arthropod species further modulates community assembly and affects plant fitness remains unclear. Using wild Brassica oleracea plants in the field, we manipulated the order of arrival of early-season herbivores that belong to different feeding guilds, namely the aphid Brevicoryne brassicae and caterpillars of Plutella xylostella. We investigated the effect of herbivore identity and order of arrival on community assembly on two B. oleracea plant populations during two growth seasons. For this perennial plant, we evaluated whether foliar herbivory also affected herbivore communities on the flowers and if these interactions affected plant seed production. Aphid infestation caused an increase in parasitoid abundance, but caterpillars modulated these effects, depending on the order of herbivore infestation and plant population. In the second growth season, when plants flowered, the order of infestation of leaves with aphids and caterpillars more strongly affected abundance of herbivores feeding on the flowers than those feeding on leaves. Infestation with caterpillars followed by aphids caused an increase in flower-feeding herbivores compared to the reversed order of infestation in one plant population, whereas the opposite effects were observed for the other plant population. The impact on plant seed set in the first reproductive year was limited. Our work shows that the identity and arrival order of early season herbivores may have long-term consequences for community composition on individual plants and that these patterns may vary among plant populations. We discuss how these community processes may affect plant fitness and speculate on the implications for evolution of plant defences.

Background Induced aboveground plant defenses against pathogens can have negative effects on belowground microbial symbionts. While a considerable number of studies have utilized chemical elicitors to experimentally induce such defenses, there is surprisingly little evidence that actual aboveground pathogens affect root-associated microbes. We report here that an aboveground fungal pathogen of common bean (Phaseolus vulgaris) induces a defense response that inhibits both the belowground formation of root nodules elicited by rhizobia and the colonization with arbuscular mycorrhizal fungi (AMF). Results Foliage of plants inoculated with either rhizobia or AMF was treated with both live Colletotrichum gloeosporioides—a generalist hemibiotrophic plant pathogen—and C. gloeosporioides fragments. Polyphenol oxidase (PPO), chitinase and β-1,3-glucanase activity in leaves and roots, as well as the number of rhizobia nodules and the extent of AMF colonization, were measured after pathogen treatments. Both the live pathogen and pathogen fragments significantly increased PPO, chitinase and β-1,3-glucanase activity in the leaves, but only PPO activity was increased in roots. The number of rhizobia nodules and the extent of AMF colonization was significantly reduced in treatment plants when compared to controls. Conclusion We demonstrate that aboveground fungal pathogens can affect belowground mutualism with two very different types of microbial symbionts—rhizobia and AMF. Our results suggest that systemically induced PPO activity is functionally involved in this above-belowground interaction. We predict that the top-down effects we show here can drastically impact plant performance in soils with limited nutrients and water; abiotic stress conditions usually mitigated by microbial belowground mutualists. Electronic supplementary material The online version of this article (doi:10.1186/s12870-014-0321-4) contains supplementary material, which is available to authorized users.