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Dihydrorotenone (DHR) is a natural pesticide widely used in farming industry, such as organic produces. DHR is a potent mitochondrial inhibitor and probably induces Parkinsonian syndrome, however, it is not known whether DHR is toxic to other systems. In the present study, we evaluated the cytotoxicity of DHR on human plasma cells. As predicted, DHR impaired mitochondrial function by decreasing mitochondrial membrane potential in plasma cells. Because mito-dysfunction leads to unfolded protein response (UPR) and endoplasmic reticulum (ER) stress, we examined the signature proteins in ER stress, including GRP78, ATF4, and CHOP. After DHR treatment, these proteins were significantly upregulated. It is reported that activation of the mitogen-activated protein kinases p38 and JNK are involved in endoplasmic reticulum stress. However, in the subsequent study, DHR was found to activate p38 but not the JNK signaling. When pre-treated with p38 inhibitor SB203580, activation of p38 and cell apoptosis induced by DHR was partially blocked. Thus, we found that DHR induced human plasma cell death by activating the p38 but not the JNK signaling pathway. Because plasma cells are very important in the immune system, this study provided a new insight in the safety evaluation of DHR application.

Grapevine (Vitis vinifera) is susceptible to many pathogens which cause significant losses to viticulture worldwide. Chemical control is available, but agro-ecological concerns have raised interest in alternative methods, especially in triggering plant immunity by elicitor treatments. The β-glucan laminarin (Lam) and its sulfated derivative (PS3) have been previously demonstrated to induce resistance in grapevine against downy mildew (Plasmopara viticola). However, if Lam elicits classical grapevine defenses such as oxidative burst, pathogenesis-related (PR)-proteins and phytoalexin production, PS3 triggered grapevine resistance via a poorly understood priming phenomenon. The aim of this study was to identify the molecular mechanisms of the PS3-induced resistance. For this purpose we studied i) the signaling events and transcriptome reprogramming triggered by PS3 treatment on uninfected grapevine, ii) grapevine immune responses primed by PS3 during P. viticola infection. Our results showed that i) PS3 was unable to elicit reactive oxygen species (ROS) production, cytosolic Ca(2+) concentration variations, mitogen-activated protein kinase (MAPK) activation but triggered a long lasting plasma membrane depolarization in grapevine cells, ii) PS3 and Lam shared a common stress-responsive transcriptome profile that partly overlapped the salicylate- (SA) and jasmonate-(JA)-dependent ones. After P. viticola inoculation, PS3 specifically primed the SA- and ROS-dependent defense pathways leading to grapevine induced resistance against this biotroph. Interestingly pharmacological approaches suggested that the plasma membrane depolarization and the downstream ROS production are key events of the PS3-induced resistance.

Background The flower bug Orius sauteri is an important polyphagous predator that is widely used for the biological control of mites and aphids. However, the optimal conditions for mass rearing of this insect are still unclear, thus limiting its application. Methodology In this study, we investigated the optimal ingredients of an artificial diet for raising O. sauteri using a microencapsulation technique. The ingredients included egg yolk (vitellus), whole-pupa homogenate of the Tussah silk moth (Antheraea paphia), honey, sucrose, rapeseed (Brassica napus) pollen and sinkaline. We tested 25 combinations of the above ingredients using an orthogonal experimental design. Using statistical analysis, we confirmed the main effect factors amongst the components, and selected five optimal combinations based on different biological and physiological characters. Principal Findings The results showed that, although different artificial diet formats significantly influenced the development and reproductive ability of O. sauteri, the complete development of O. sauteri to sexual maturity could only be achieved by optimizing the artificial diet according to specific biological characters. In general, pupae of A. paphia had more influence on O sauteri development than did artificial components. The results of a follow-up test of locomotory and respiratory capacity indicated that respiratory quotient, metabolic rate and average creeping speed were all influenced by different diets. Furthermore, the field evaluations of mating preference, predatory consumption and population dispersion also demonstrated the benefits that could be provided by optimal artificial diets. Conclusions A microencapsulated artificial diet overcame many of the difficulties highlighted by previous studies on the mass rearing of O. sauteri. Optimization of the microencapsulated artificial diet directly increased the biological and physiological characters investigated. Successive physiological tests and field investigations were used to evaluate the outcome of different artificial diet combinations on the quality of the reared O. sauteri.

Schemes designed to make farming landscapes less hostile to wildlife have been questioned because target taxa do not always respond in the expected manner. Microbats are often overlooked in this process, yet persist in agricultural landscapes and exert top-down control of crop pests. We investigated the relationship between microbats and measures commonly incorporated into agri-environment schemes, to derive management recommendations for their ongoing conservation. We used acoustic detectors to quantify bat species richness, activity, and feeding in 32 linear remnants and adjacent fields across an agricultural region of New South Wales, Australia. Nocturnal arthropods were simultaneously trapped using black-light traps. We recorded 91,969 bat calls, 17,277 of which could be attributed to one of the 13 taxa recorded, and 491 calls contained feeding buzzes. The linear remnants supported higher bat activity than the fields, but species richness and feeding activity did not significantly differ. We trapped a mean 87.6 g (617.6 g SE) of arthropods per night, but found no differences in biomass between land uses. Wider linear remnants with intact native vegetation supported more bat species, as did those adjacent to unsealed, as opposed to sealed roads. Fields of unimproved native pastures, with more retained scattered trees and associated hollows and logs, supported the greatest bat species richness and activity. We conclude that the juxtaposition of linear remnants of intact vegetation and scattered trees in fields, coupled with less-intensive land uses such as unimproved pastures will benefit bat communities in agricultural landscapes, and should be incorporated into agri-environment schemes. In contrast, sealed roads may act as a deterrent. The ‘‘wildlife friendly farming’’ vs ‘‘land sparing’’ debate has so far primarily focussed on birds, but here we have found evidence that the integration of both approaches could particularly benefit bats.

Trichoderma spp. are versatile opportunistic plant symbionts which can colonize the apoplast of plant roots. Microarrays analysis of Arabidopsis thaliana roots inoculated with Trichoderma asperelloides T203, coupled with qPCR analysis of 137 stress responsive genes and transcription factors, revealed wide gene transcript reprogramming, proceeded by a transient repression of the plant immune responses supposedly to allow root colonization. Enhancement in the expression of WRKY18 and WRKY40, which stimulate JA-signaling via suppression of JAZ repressors and negatively regulate the expression of the defense genes FMO1, PAD3 and CYP71A13, was detected in Arabidopsis roots upon Trichoderma colonization. Reduced root colonization was observed in the wrky18/wrky40 double mutant line, while partial phenotypic complementation was achieved by over-expressing WRKY40 in the wrky18 wrky40 background. On the other hand increased colonization rate was found in roots of the FMO1 knockout mutant. Trichoderma spp. stimulate plant growth and resistance to a wide range of adverse environmental conditions. Arabidopsis and cucumber (Cucumis sativus L.) plants treated with Trichoderma prior to salt stress imposition show significantly improved seed germination. In addition, Trichoderma treatment affects the expression of several genes related to osmo-protection and general oxidative stress in roots of both plants. The MDAR gene coding for monodehydroascorbate reductase is significantly up-regulated and, accordingly, the pool of reduced ascorbic acid was found to be increased in Trichoderma treated plants. 1-Aminocyclopropane-1-carboxylate (ACC)-deaminase silenced Trichoderma mutants were less effective in providing tolerance to salt stress, suggesting that Trichoderma, similarly to ACC deaminase producing bacteria, can ameliorate plant growth under conditions of abiotic stress, by lowering ameliorating increases in ethylene levels as well as promoting an elevated antioxidative capacity., Author Summary Trichoderma fungi have been developed as biocontrol agents and are applied to protect and improve crop yields. Colonization of plant roots by Trichoderma can protect plants against diseases and environmental stresses such as salinity and drought, and an improve plant growth and development. To better understand the mechanism underlining the plant-Trichoderma interaction we followed changes in global gene expression in colonized Arabidopsis roots. We associate the known gene biological function to the processes of root colonization and abiotic stress tolerance mediated by Trichoderma. Using Arabidopsis mutant lines we show the function of a subset of those genes in root colonization. We show that wrky18 and wrky40 transcription factors activate and suppress the expression of different genes in order to allow successful root colonization. We also combine the gene expression data together with the measurement of ascorbic acid level to demonstrate that salt stress tolerance offered by Trichoderma is dependent on activation of the plant antioxidant defense machinery. Using Trichoderma lines mutated in the ACC deaminase gene, we demonstrate that reduction of ethylene levels is also essential in achieving salt tolerance. This study represents an important step forward in understanding the nature of the non-pathogenic plant Trichoderma interaction, and may contribute to the efforts to improve Trichoderma biocontrol abilities.

Food production is considered to be the main source of human impact on the environment and the concerns about detrimental effects of pesticides on biodiversity and human health are likely to lead to an increasingly restricted use of chemicals in agriculture. Since the first successful field trial, pheromone based mating disruption enabled sustainable insect control, which resulted in reduced levels of pesticide use. Organic farming is one of the fastest growing segments of agriculture and with the continuously growing public concern about use of pesticides, the main remaining challenge in increasing the safety of the global food production is to identify appropriate alternative mating disruption approaches for the numerous insect pests that do not rely on chemical communication. In the present study, we show for the first time that effective mating disruption based on substrate-borne vibrational signals can be achieved in the field. When disruptive vibrational signals were applied to grapevine plants through a supporting wire, mating frequency of the leafhopper pest Scaphoideus titanus dropped to 9 % in semi-field conditions and to 4 % in a mature vineyard. The underlying mechanism of this environmentally friendly pest-control tactic is a masking of the vibrational signals used in mate recognition and location. Because vibrational communication is widespread in insects, mating disruption using substrate vibrations can transform many open field and greenhouse based farming systems.

Organic farming is one of the most successful agri-environmental schemes, as humans benefit from high quality food, farmers from higher prices for their products and it often successfully protects biodiversity. However there is little knowledge if organic farming also increases ecosystem services like pest control. We assessed 30 triticale fields (15 organic vs. 15 conventional) and recorded vascular plants, pollinators, aphids and their predators. Further, five conventional fields which were treated with insecticides were compared with 10 non-treated conventional fields. Organic fields had five times higher plant species richness and about twenty times higher pollinator species richness compared to conventional fields. Abundance of pollinators was even more than one-hundred times higher on organic fields. In contrast, the abundance of cereal aphids was five times lower in organic fields, while predator abundances were three times higher and predator-prey ratios twenty times higher in organic fields, indicating a significantly higher potential for biological pest control in organic fields. Insecticide treatment in conventional fields had only a short-term effect on aphid densities while later in the season aphid abundances were even higher and predator abundances lower in treated compared to untreated conventional fields. Our data indicate that insecticide treatment kept aphid predators at low abundances throughout the season, thereby significantly reducing top-down control of aphid populations. Plant and pollinator species richness as well as predator abundances and predator-prey ratios were higher at field edges compared to field centres, highlighting the importance of field edges for ecosystem services. In conclusion organic farming increases biodiversity, including important functional groups like plants, pollinators and predators which enhance natural pest control. Preventative insecticide application in conventional fields has only short-term effects on aphid densities but long-term negative effects on biological pest control. Therefore conventional farmers should restrict insecticide applications to situations where thresholds for pest densities are reached.

Neighborhood characteristics, such as healthy food availability, have been associated with consumption of healthy food. Little is known about the influence of the local food environment on other dietary choices, such as the decision to consume organic food. We analyzed the associations between organic produce consumption and demographic, socioeconomic and neighborhood characteristics in 4,064 participants aged 53-94 in the Multi-Ethnic Study of Atherosclerosis using log-binomial regression models. Participants were classified as consuming organic produce if they reported eating organic fruits and vegetables either "sometimes" or "often or always". Women were 21% more likely to consume organic produce than men (confidence interval [CI]: 1.12-1.30), and the likelihood of organic produce consumption was 13% less with each additional 10 years of age (CI: 0.84-0.91). Participants with higher education were significantly more likely to consume organic produce (prevalence ratios [PR] were 1.05 with a high school education, 1.39 with a bachelor's degree and 1.68 with a graduate degree, with less than high school as the reference group [1.00]). Per capita household income was marginally associated with produce consumption (p = 0.06), with the highest income category more likely to consume organic produce. After adjustment for these individual factors, organic produce consumption was significantly associated with self-reported assessment of neighborhood produce availability (PR: 1.07, CI: 1.02-1.11), with an aggregated measure of community perception of the local food environment (PR: 1.08, CI: 1.00-1.17), and, to a lesser degree, with supermarket density (PR: 1.02: CI: 0.99-1.05). This research suggests that both individual-level characteristics and qualities of the local food environment are associated with having a diet that includes organic food.