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Tomato is more prone to Tuta absoluta invasion and damages as compared to other host plants but the mechanism behind this preference has not been elucidated. Here, two contrasting host preference plants, tomato and eggplant, were used to investigate biochemical and transcriptomic modifications induced by T. absoluta infestation. Biochemical analysis at 0–72 h post T. absoluta infestation revealed significantly reduced concentrations of amino acid, fructose, sucrose, jasmonic acid, salicylic acid, and total phenols in tomato compared to eggplant, mainly at 48 h post T. absoluta infestation. Transcriptome analysis showed higher transcript changes in infested eggplant than tomato. Signaling genes had significant contributions to mediate plant immunity against T. absoluta, specifically genes associated with salicylic acid in eggplant. Genes from PR1b1, NPR1 , NPR3, MAPKs , and ANP1 families play important roles to mitigate T. absoluta infestation. Our results will facilitate the development of control strategies against T. absoluta for sustainable tomato production.

Mealybugs, such as Phenacoccus solenopsis, are highly sexually dimorphic. Winged adult males present such remarkable morphological differences from females that, to the untrained eye, conspecific adults of both sexes of P. solenopsis may be considered as two different insect species. A method to investigate sex-dimorphic mechanisms is by evaluating gene expression using RT-qPCR. However, the accuracy and consistency of this technique depend on the reference gene(s) selected. In this study, we analyzed the expression of 10 candidate reference genes in male and female P. solenopsis at different development stages, using common algorithms including the ΔCt method, NormFinder, geNorm, BestKeeper, and a web-based analysis tool, RefFinder. The results showed that EF1-β, RP-L32 and RP-18S were selected as the most stable genes by both the ΔCt method and NormFinder; TUB-α was the most stable gene identified by BestKeeper; and RP-L40 and RP-L32 were the most stable genes ranked by geNorm. RefFinder, a comprehensive analysis software, ranked the ten genes and determined EF1-β and RP-L32 as the most suitable reference genes for the various developmental stages in male and female P. solenopsis. Furthermore, the two most suitable reference genes were validated by examining expression of the juvenile hormone acid O-methytransferase (JHAMT) gene. Results of the validation portion of the study showed that JHAMT expression was sex-biased towards males and exhibited a dynamic and classic expression pattern among the P. solenopsis developmental stages. The results can help further our knowledge on the molecular mechanisms underlying sexual dimorphic development in P. solenopsis.

Microbial electrosynthesis systems (MESs) can convert carbon dioxide into added value compounds using microorganisms as catalyst, which is expected to help achieve conversion of greenhouse gases into resources. However, the synthetic efficiency of MESs is far behind the industry requirements. In this study, carbon cloth surfaces were bonded with carboxyl groups by electrochemical reduction of aryl diazonium salts and then used as a cathode in MESs reactors. The results showed that the hydrophilicity of the carbon cloth surfaces improved after the carboxyl groups were modified. However, weaker current of cyclic voltammetry was obtained in the modified cathode. Significant differences were observed between modified (CA-H, CA-M, CA-L) and non-modified cathode (CK) during the start-up period. After 48h, the hydrogen production rate of CA-H, CA-M, CA-L was 21.45, 28.60, and 22.75 times higher than CK. After 120h, the acetate accumulation concentration of CA-H, CA-M, CA-L was 2.01, 2.43, and 1.44 times higher than CK. After 324h, there was little difference in the electrochemical activity of cathodic biofilm and protein content (about 0.47 mg·cm

The removal efficiencies of environmental pollutants in a microbial electrolysis system (MES) with a biocathode are highly affected by the externally applied voltage. Although the cathode biofilm plays a key role in the pollution removal, its response to the applied voltage is still unknown. A two-chambered MES with a biocathode was constructed to study the impact of the different applied voltages (0.4, 0.5, 0.6, 0.7, and 0.8 V) on the sulfate reduction, extracellular polymer formation, and cathodic bacterial community. The results show that the current output and coulomb and COD removals of the MES are positively correlated with the applied voltage ranging from 0.4 to 0.8 V. The sulfate reduction rate first increases and then decreases with increasing voltage in the MES. The maximum sulfate reductive rate[78.9 g·(m

A simple, sensitive and reliable analytical method was developed for the simultaneous determination of 22 carbamate insecticides and 17 mycotoxins in cereals by ultra high performance liquid chromatography electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS). Carbamates and mycotoxins were extracted from cereal samples using a QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) procedure without any further clean-up step. The extract was diluted with water containing 0.1% formic acid and 5.0mM ammonium acetate, and analyzed by LC-MS/MS on a Waters Acquity BEH C(18) column with water (0.1% formic acid, 0.50mM ammonium acetate)/methanol as mobile phase with gradient elution. Matrix-matched calibration was used for quantification. Blank samples (rice, wheat and corn) were fortified at 5, 10 and 50 μg/kg except for five zearalenonic compounds at 25, 50 and 250 μg/kg, and recoveries were in the range of 70-120%. Relative standard deviations were lower than 20% in all cases. The LOQ values were in the range of 0.20-29.7 μg/kg. The method is suitable for the simultaneous determination of carbamate insecticides and mycotoxins in cereals. The total time required for the analysis of one sample, including sample preparation, was about 35 min.

We studied the biological characteristics and chemical control of Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) on tomatoes under laboratory conditions within the temperature and relative humidity ranges of 25 ± 2°C and 70 ± 5% RH, respectively. Results show that the nymphal stage of males (16.3 ± 0.2 days) is longer that for females (15.4 ± 0.5 days) and the survival rate of second instars is lower (56.5%) than for first (80.5%) and third instars (68.1%). The average lifespan of males (1.8 ± 0.2 days) is significantly shorter than for females (42.6 ± 1.1 days), and the average fecundity per adult female is 134.6 ± 16.3 crawlers. Phenacoccus solenopsis grows rapidly in the end of the nymphal stage, and the size of adult females is nearly twice that of third instars. Control of P. solenopsis using imidacloprid was increased by nearly 35% by adding laundry detergent and this was most effective on the first instars. These results add to our scientific understanding how to improve effect...

The objective of this study was to identify the aggregation pheromone of the melon thrips Thrips palmi, a major pest of vegetable and ornamental plants around the world. The species causes damage both through feeding activities and as a vector of tospoviruses, and is a threat to world trade and European horticulture. Improved methods of detecting and controlling this species are needed and the identification of an aggregation pheromone will contribute to this requirement. Bioassays with a Y-tube olfactometer showed that virgin female T. palmi were attracted to the odour of live males, but not to that of live females, and that mixed-age adults of both sexes were attracted to the odour of live males, indicating the presence of a male-produced aggregation pheromone. Examination of the headspace volatiles of adult male T. palmi revealed only one compound that was not found in adult females. It was identified by comparison of its mass spectrum and chromatographic details with those of similar compounds. This compound had a structure like that of the previously identified male-produced aggregation pheromone of the western flower thrips Frankliniella occidentalis. The compound was synthesised and tested in eggplant crops infested with T. palmi in Japan. Significantly greater numbers of both males and females were attracted to traps baited with the putative aggregation pheromone compared to unbaited traps. The aggregation pheromone of T. palmi is thus identified as (R)-lavandulyl 3-methyl-3-butenoate by spectroscopic, chromatographic and behavioural analysis.

Herbivore injury has indirect effects on the growth and performance of host plants through photosynthetic suppression. It causes uncertain reduction in photosynthesis, which likely depends on the degree of infestation. Rapid light curves provide detailed information on the saturation characteristics of electron transport as well as the overall photosynthetic performance of a plant. We examined the effects of different intensities of infestation of the invasive mealybug, Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), on the relative chlorophyll content and rapid light curves of tomato Solanum lycopersicum L. leaves using a chlorophyll meter and chlorophyll fluorescence measurement system, respectively, under greenhouse conditions. After 38 d of P. solenopsis feeding, relative chlorophyll content of tomato plants with initial high of P. solenopsis was reduced by 57.3%. Light utilization efficiency (α) for the initial high-density treatment was reduced by 42.4%. However, no significant difference between initial low-density treatment and uninfested control was found. The values of the maximum electron transport rate and minimum saturating irradiance for initial high-density treatment were reduced by 82.0 and 69.7%, respectively, whereas the corresponding values for low-density treatment were reduced by 55.9 and 58.1%, respectively. These data indicated that changes were induced by P. solenopsis feeding in the relative chlorophyll content and chlorophyll fluorescence of infested tomato plants. The results indicating that low initial infestation by P. solenopsis caused no change in relative leaf chlorophyll content or light utilization efficiency could have been because the plants rapidly adapted to P. solenopsis feeding or because of compensatory photosynthesis.

Mobile commerce becomes increasingly popular in China. The applications of mobile commerce are rich. Especially, mobile brokerage service is an emerging application of mobile commerce in the brokerage industry. Although mobile brokerage service has many advantages, the number of investors using the MBS to conduct stock trading is far smaller than those using other trading methods. Lack of trust is a big obstacle for investors to adopt mobile brokerage service. Most studies only consider the impact factors of trust in one environment and rare research explores trust building by trust transference across different environment. Based on mobile brokerage service, we build a model of trust transference from online to mobile setting and empirically test it. The results indicate trust in the online brokerage service of a brokerage firm influences cognitive beliefs about the firm's mobile brokerage service. Keywords-mobile commerce;mobile brokerage service; trust; trust transfer

Lack of trust in mobile brokerage service is a primary reason why many investors do not conduct trading in mobile environment. This study propose a model of initial investor trust in mobile brokerage service and consider the effect of six antecedent variables on shaping an investor initial trust and intention in mobile brokerage service. The six variables are perceived ubiquity, service compatibility, information quality, perceived reputation, perceived security and propensity to trust. We test the proposed model by survey data collected and use a structural equation modeling techniques to analyze the causalities. The results show support for the proposed model and confirm its robustness in predicting investors' initial trust and intention in mobile brokerage service. The findings provide useful suggestions and implication for the academician and practitioners.

In the Lepidoptera, odorant signals are thought to be mediated by general odorant binding proteins (GOBPs) in the sensillar lymph surrounding the olfactory receptors. We describe the identification and characterization of two new cDNAs encoding GOBPs from the antennae of the diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), a species for which no GOBPs have been identified to date. We focused our investigation on this olfactory protein family by using reverse transcription–polymerase chain reaction strategies. The deduced amino acid sequences of PxylGOBP1 and PxylGOBP2 revealed open reading frames of 168 and 163 amino acids, respectively, with six cysteine residues in conserved positions relative to other known GOBPs. The alignment of the mature PxylGOBPs with other Lepidoptera GOBPs showed high sequence identity (70–80%) with other full-length sequences from GenBank. Sequence identity between PxylGOBP1and PxylGOBP2 was only 50%, suggesting that the two proteins belong to different classes of lepidopteran GOBPs. The expression patterns of the two PxylGOBP genes, with respect to tissue distribution and sex, were further investigated by reverse transcription-polymerase chain reaction (RT-PCR) and real-time PCR. Although the two GOBP genes were expressed only in the antennae of both sexes, reflecting the antennal specificity of GOBPs, the transcription levels of these genes depended on the sex, the age, the mating status, and the genes.

A multi-source information fusion multiple hypotheses tracking algorithm is presented, which is capable of track initiating, track termination, track continuation. The algorithm is either suitable for spot fusion or suitable for track fusion. Main processing flow and design concept are described. Technique problems in performing MHT algorithm are put forward. Feasibility and practicability of the MHT algorithm for multi-source are validated by simulation and real experiment results.

The reactions of 1,1,2,2-tetrafluoro-1,2-disilacyclobutene with benzophenone, pinacolone, acrolein and crotonaldehyde are studied at −30°C. The product formation is best rationalized in terms of an initial attack by the carbonyl oxygen on one of the two silicon atoms, which assists the cleavage of the Si-Si bond to form a diradical intermediate, followed by either ring closure or hydrogen abstraction. The reactions are so chosen to provide information about steric, inductive and resonance effects.