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Mikania micrantha Kunth is a fast-growing global invasive weed species that causes severe damage to natural ecosystems and very large economic losses of forest and crop production. Although Puccinia spegazzinii can effectively inhibit the growth of M. micrantha and is used as a biological control strain in many countries, the mechanism of inhibiting the growth of M. micrantha is not clear. Here, we used a combination of phenotypic, enzyme activity, transcriptomic, and metabolomic approaches to study the response of M. micrantha after infection by P. spegazzinii. In the early stages of rust infection, jasmonic acid (JA), jasmonoyl-isoleucine (JA-Ile), and salicylic acid (SA) levels in infected leaves were significantly lower than those in uninfected leaves. In teliospore initial and developed stages of P. spegazzinii, JA and JA-Ile levels substantially increased by more than 6 times, which resulted in a significant decrease in the accumulation of defense hormone SA in infected leaves of M. micrantha. The contents of plant growth-promoting hormones were significantly reduced in the infected plants as a result of substantial downregulation of the expression of key genes related to hormone biosynthesis. Furthermore, rust infection led to high levels of reactive oxygen species in chloroplasts and the destruction of chlorophyll structure, which also led to decreased photosynthetic gene expression, net photosynthetic rate, activity of Rubisco, and levels of important organic acids in the Calvin cycle. We hypothesized that after P. spegazzinii infection, JA or JA-Ile accumulation not only inhibited SA levels to promote rust infection and development, but also impeded the rapid growth of M. micrantha by affecting plant growth hormones, carbon, and nitrogen metabolic pathways.

The major plant pest fall armyworm (FAW),Spodoptera frugiperda, is native to the Americas and has colonized African and Asian countries in the Eastern hemisphere since 2016, causing severe damage to multiple agricultural crop species. However, the genetic origin of these invasive populations require more in-depth exploration. We analyzed genetic variation across FAW genomes of 153 newly sequenced individuals from Eastern hemisphere and 127 individuals mostly originating from the Americas. The global genetic structure of FAW shows that the FAW in American has experienced deep differentiation, largely consistent with the Z-chromosomalTpihaplotypes commonly used to differentiate “corn-strain” and “rice-strain” populations. Results indicate that the invasive Eastern hemisphere populations are different from the American ones and have relatively homogeneous population structure, consistent with the common origin and recent spreading from Africa to Asia. Our analyses suggest that north-and central American “corn-strain” FAW are the most likely sources of the invasion into the Eastern hemisphere. Furthermore, evidence based on genomic, transcriptomic and mitochondrial haplotype network analysis suggest that there has been an earlier independent introduction of FAW into Africa that introgressed into the recent invasive population.

The rapid wide-scale spread of fall armyworm (Spodoptera frugiperda) has caused serious crop losses34 globally. However, differences in the genetic background of subpopulations and the mechanisms of rapid adaptation behind the invasion are still not well understood. Here we report the assembly of a 390.38-M chromosome-level genome of fall armyworm using Pacific Bioscience (PacBio) and Hi-C sequencing technologies with scaffold N50 of 12.7 M consisting of 22260 annotated protein-coding genes. Genome-wide resequencing of 103 samples from 16 provinces in China revealed that the fall armyworm population comprises a complex inter-strain hybrid, mainly with the corn-strain genetic background and less of the rice-strain, which highlights the inaccuracy of strain identification using mitochondrial or Triosephosphate isomerase (Tpi) genes. Analysis of genes related to pesticide- and Bt-resistance showed that the risk of fall armyworm developing resistance to conventional pesticides is very high. Laboratory bioassay results showed that insects invading China carry resistance to organophosphate and pyrethroid pesticides, but are sensitive to genetically modified maize expressing Bacillus thuringiensis (Bt) toxins Cry1Ab in field experiments. Additionally, two mitochondrial fragments are inserted into the nuclear genome, and the insertion event occurred after the differentiation of the two strains. This study represents a valuable advance toward improving management strategies for fall armyworm.

Nano-Cu-based materials have many applications in the microelectronics and aerospace industries, which not only maintain the advantages of copper materials, but also make up for the shortage of cop...

The polyphagous cotton leafworm (Spodoptera littoralis) is one of the most destructive herbivorous insects worldwide. The present study reports the complete mitochondrial genome of S. littoralis collected from Egypt. The circular-mapping mitogenome was 15,408 bp in length with an overall A + T content of 81.1%, encoding a common set of 37 genes, including 13 protein-coding genes (PCGs), 22 tRNA genes, and two rRNA genes. Most PCGs were found to use conventional ATN as the start codon and TAN as the stop codon. The phylogenetic tree based on the nucleic acid sequences of 13 shared PCGs of 29 Noctuidae species revealed that S. littoralis and Spodoptera litura are sister species. The data in this study will be helpful to understand geographical genetic variations, phylogenetic relationships, and species identification of S. littoralis.

The CuO-Al2O3 composite powders were synthesized by chemical coprecipitation method, then, after sintering in tube furnace of 400 °C for 1 h at atmosphere of hydrogen and nitrogen, the comp...

A novel gas sensor based on Ag nanoparticle-doped WO3 nanosheets with various doping levels was successfully fabricated via a two-step process that included a facile acid-precipitation method followed by a dipping route. The crystal structures, morphologies and composition of the as-obtained sensing materials were characterized by XRD, SEM, TEM and XPS methods. Gas sensing tests revealed that the 2 at.% Ag NPs-WO3 nanosheets possess excellent gas sensing performance for formaldehyde (HCHO). The sensitivity of the material towards 100 ppm HCHO was as high as 20.83 at an optimum operating temperature of 300 °C, which is higher than that of pure one even at lower working temperatures. Furthermore, the rapid response/recovery speeds (5 s/5 s), great selectivity and outstanding long-term stability were also exhibited for the 2 at.% Ag NPs-modified WO3 sensor. The improvement of sensing performance is related to the active space charge regions around the interface of Ag particles and WO3, and the catalytic role of Ag nanoparticles as the possible sensing mechanism was proposed. The Ag NP-decorated WO3 with superior gas sensing property is expected to be a promising candidate for formaldehyde detection in practical application and industrial production.

Summary The reversibility and cyclability of anionic redox in battery electrodes hold the key to its practical employments. Here, through mapping of resonant inelastic X-ray scattering (mRIXS), we have independently quantified the evolving redox states of both cations and anions in Na2/3Mg1/3Mn2/3O2. The bulk Mn redox emerges from initial discharge and is quantified by inverse partial fluorescence yield (iPFY) from Mn-L mRIXS. Bulk and surface Mn activities likely lead to the voltage fade. O-K super-partial fluorescence yield (sPFY) analysis of mRIXS shows 79% lattice oxygen redox reversibility during the initial cycle, with 87% capacity sustained after 100 cycles. In Li1.17Ni0.21Co0.08Mn0.54O2, lattice oxygen redox is 76% initial-cycle reversible but with only 44% capacity retention after 500 cycles. These results unambiguously show the high reversibility of lattice oxygen redox in both Li-ion and Na-ion systems. The contrast between Na2/3Mg1/3Mn2/3O2 and Li1.17Ni0.21Co0.08Mn0.54O2 systems suggests the importance of distinguishing lattice oxygen redox from other oxygen activities for clarifying its intrinsic properties.

Fertilization can trigger bottom-up effects on crop plant–insect pest interactions. The intensive use of nitrogen fertilizer has been a common practice in rice production, while the yield has long been challenged by the white-backed planthopper, Sogatella furcifera (Horváth). High nitrogen fertilization can facilitate S. furcifera infestation, however, how nitrogen fertilizer leads to high S. furcifera infestation and the nutritional interactions between rice and S. furcifera are poorly understood. Here, we evaluated the effects of various levels of nitrogen fertilizer application (0–350 kg/ha) on rice, and subsequently on S. furcifera performance. We found that higher nitrogen fertilizer application: (1) increases the preference of infestation behaviors (feeding and oviposition), (2) extends infestation time (adult lifespan), and (3) shortens generation reproduction time (nymph, pre-oviposition, and egg period), which explain the high S. furcifera infestation ratio on rice paddies under high nitrogen conditions. Moreover, high nitrogen fertilizer application increased all tested rice physical indexes (plant height, leaf area, and leaf width) and physiological indexes (chlorophyll content, water content, dry matter mass, and soluble protein content), except for leaf thickness, which was reduced. Correlation analysis indicated that the specific rice physical and/or physiological indexes were conducive to the increased infestation behavior preference, extended infestation time, and shortened generation reproduction time of S. furcifera. The results suggested that nitrogen fertilizer triggers bottom-up effects on rice and increases S. furcifera populations. The present study provides an insight into how excess nitrogen fertilization shapes rice–planthopper interactions and the consequent positive effect on S. furcifera infestation.

The Cydia pomonella granulovirus (CpGV) has been used as a biological control agent of codling moth (Cydia pomonella), a severe global pest on pome fruit. Despite the economic importance, our knowledge of its molecular biology is still limited and a detailed picture of its gene expression is still missing. Here, we sequenced the transcriptome of codling moth larvae infected with the Mexican isolate CpGV-M and analyzed the expression of viral genes at 12, 48, and 96 h post infection (hpi). The results showed that two genes (p6.9 and pp31/39K) related to DNA binding of virus production, were highly expressed at 48 and 96 hpi. From 48 to 96 hpi, the expression of genes associated with virus replication and dissemination decreased, whereas the expression of genes related to infectious virion production and per os infectivity increased. This study provides a comprehensive view of CpGV gene expression patterns in host larvae.

Whole-genome duplication (WGD) has been observed across a wide variety of eukaryotic groups, contributing to evolutionary diversity and environmental adaptability. Mollusks are the second largest group of animals, and are among the organisms that have successfully adapted to the nonmarine realm through aquatic-terrestrial (A-T) transition, and no comprehensive research on WGD has been reported in this group. To explore WGD and the A-T transition in Mollusca, we assembled a chromosome-level reference genome for the giant African snailAchatina immaculata, a global invasive species, and compared the genomes of two giant African snails (A. immaculataandAchatina fulica) to the other available mollusk genomes. The chromosome-level macrosynteny, colinearity blocks, Ks peak and Hox gene clusters collectively suggested the occurrence of a WGD event shared byA. immaculataandA. fulica. The estimated timing of this WGD event (∼70 MYA) was close to the speciation age of the Sigmurethra-Orthurethra (within Stylommatophora) lineage and the Cretaceous-Tertiary (K-T) mass extinction, indicating that the WGD reported herein may have been a common event shared by all Sigmurethra-Orthurethra species and could have conferred ecological adaptability and genomic plasticity allowing the survival of the K-T extinction. Based on macrosynteny, we deduced an ancestral karyotype containing 8 conserved clusters for the Gastropoda-Bivalvia lineage. To reveal the mechanism of WGD in shaping adaptability to terrestrial ecosystems, we investigated gene families related to the respiration, aestivation and immune defense of giant African snails. Several mucus-related gene families expanded early in the Stylommatophora lineage, functioning in water retention, immune defense and wound healing. The hemocyanins, PCK and FBP families were doubled and retained after WGD, enhancing the capacity for gas exchange and glucose homeostasis in aestivation. After the WGD, zinc metalloproteinase genes were highly tandemly duplicated to protect tissue against ROS damage. This evidence collectively suggests that although the WGD may not have been the direct driver of the A-T transition, it provided an important legacy for the terrestrial adaptation of the giant African snail.

The oxygen deficiency is an important factor to affect the electrochemical properties of spinel LiNi 0.5 Mn 1.5 O 4 . In this study, we investigated how oxygen deficiency in spinel LiNi 0.5 Mn 1.5 O 4 was affected by calcination temperature and oxygen partial pressure. The oxygen deficiency as a function of calcination temperatures has been modeled. Doping elements have influence on oxygen deficiency. The oxygen dissipation of Cr-doped compounds LiNi 0.45 Cr 0.1 Mn 1.45 O 4 at high temperature is less than pristine LiNi 0.5 Mn 1.5 O 4 . Under the same calcination and cooling condition, there more oxygen deficiency remained in Fe and Cr-doped compounds than in pristine LiMn 1.5 Ni 0.5 O 4 . The coulomb efficiencies of LiNi 0.45 Cr 0.1 Mn 1.45 O 4 in the first charge and discharge cycle reached a high value of 89.1%.

Bactrocera minax, one of the most devastating citrus pests in Asia, has two developmental stages (mature larva and pupa) that complete their life cycle in the soil. Currently, southern China has a climate with abundant autumn rains, and soil moisture can be a major factor affecting the survival of larvae and pupae of B. minax. In the present study, we evaluated the effects of water immersion and high soil moisture content on the development of mature larvae and pupae of B. minax. When immersed in water for 1 d, 100% of mature larvae of B. minax were knocked out. When larvae were immersed for less than 6 d, however, more than 92% of knocked-out larvae recovered within 24 h. The days of water immersion with 50% and 90% recovery ratios (indicated as RD50 and RD90) were 10.3 d and 6.4 d, respectively. When larvae were immersed less than 6 d, the mortality ratios of larvae were not significantly different from those that were not immersed at all. The days of immersion causing 50% and 90% mortality of larvae (MD50 and MD90, respectively) were 7.6 d and 11.1 d, respectively. The pupation ratios of larvae were also observed to be not significantly different compared to non-immersion, and the days of immersion causing 50% and 90% pupation (PD50 and PD90, respectively) were 6.6 d and 0.8 d, respectively. Larval respiration rates were reduced after water immersion as a strategy for larval survival. High water content was not detrimental to pupae of B. minax. Adult emergence did not significantly decrease in soil with high water content, even though pupae were under those conditions for 161&ndash, 175 d. The respiration rates of pupae were lower in soil with different moisture levels and were not significantly different, which ensured the survival of pupae in high water content. Reduced respiration rate is a strategy for survival of larvae and pupae, and remarkable tolerance to high moisture conditions could explain the high rate of spread and geographical distribution of B. minax. The results of this study provide a reference for the occurrence and control of B. minax.

In this paper, the nano-powder of copper oxide was prepared by the hydrothermal synthesis method. The molybdenum carbide copper composite powder was prepared by the sol-gel SHS process with nano-copper oxide as copper source, polyvinyl alcohol as carbon source and ammonium molybdate as molybdenum source. Results indicate that the oxide copper powder was prepared under the condition of the reaction endpoint PH value 9, stirring intensity 1000rpm, reaction time 20min and reaction temperature 70°C. The oxide copper powder was incomplete nano-crystalline, the morphology was spherical class, and the diameter was about 50 nm. Under the condition of the reduction temperature 900°C and reduction time 60min, the molybdenum carbide copper composite powder was prepared by the sol-gel SHS method taken the nano-copper oxide, polyvinyl alcohol and ammonium molybdate as raw materials. The composite was crystal and spherical class. The diameter was about 150 nm.The product was molybdenum carbide and molybdenum ca...

Tin oxides SnO2-Sn3O4 was recovered from tin anode slime via pretreatment process, and creatively applied in ultrasensitive formaldehyde detection by doping La2O3 using high energy ball milling method. Composition, morphology, structure and chemical state of the samples were characterized in detail by XRF, FT-IR, XRD, SEM, HRTEM, XPS techniques. Gas sensing results showed that 1.0 ωt. % La2O3-modified SnO2-Sn3O4 revealed a prominently ultrahigh sensitivity of 117.27 towards 100 ppm formaldehyde, which was 4.9 times higher than pristine SnO2-Sn3O4, as well as rapid response/recovery speed (3 s/3 s) at 220 °C. Furthermore, the sensor was also found to exhibit an ultra-low detection limit of 80 ppb HCHO (S = 1.44). Outstanding selectivity, great repeatability to ppb-level HCHO and remarkable long-term stability were also displayed. The effect of doping appropriate amount of La2O3 and the possible sensing mechanism were investigated particularly. Complex hetero-structures, mixed-valence and catalytic activity of La2O3 made pivotal contributions to the improvement of HCHO sensing properties. The ultimate concept is to realize cycling economy, not only to develop a promising excellent performance formaldehyde sensor from industrial waste to increase the economic efficiency, but also to make a great contribution to environment protection and increase the value of tin slime.

• Bactrocera minax is an economically important pest of citrus. • Protein supplements showed a positive effect on the survival and reproduction of adults B. minax. • These findings provide deeper understanding of the biological characteristics of B. minax that could be utilized for an effective control., Bactrocera minax (Enderlein) (Diptera: Tephritidae) is a major citrus pest in China, whose artificial rearing technology of the adult is not well documented to date. In this study, we tried to determine if supplementing proteins to the adult diet could result in the enhancement of some fitness parameters of B. minax. Four feeds with varying protein source were provided as F0 (water), F1 (sucrose), F2 (sucrose + yeast), and F3 (sucrose + peptone). F0 and F1 being the control, F2 and F3 were protein food types. The results showed that adults fed by F2 and F3 lived longer with 40.1 d and 32.8 d, respectively, had reduced death rates (death peaks were delayed for 5.6 d and 4.1 d, respectively), increased mating frequencies (8.1 and 5.3 per females, 4.7 and 7.3 per males, respectively), and longer mating durations (with 42 d and 34 d). In addition, females recorded an increased adult ovary development, more egg load (with 94.8 and 77.3 brood eggs per ovary) and to greater oviposition rates of 63.2 eggs/female and 19.3 eggs/female. Based on our results, protein supplements enhanced B. minax survival, mating, and fecundity. This study does not only provide basic knowledge to implement artificial rearing of B. minax, but also deepens our understanding on its physiology that could be used to enhance the management of the pest.

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In this paper, nano-carbon black and polypropylene were used as raw materials to prepare Φ18 mm disc working electrode by the process of hot extrusion mixing-hot embossing-electrode preparing. Saturated calomel electrode was used as a reference electrode and graphite plate as the auxiliary electrode to study the electrochemical properties of disc working electrode in the vanadium redox battery solution. The results indicated that the higher nano-carbon black content was, the higher electrochemical activity and the worse corrosion resistance in the nano-carbon black polypropylene disc working electrode would be. The suitable nano-carbon black content was 45%. The disc working electrode with 45% nano-carbon black content possessed a hydrogen evolution potential at −1·0 V and an oxygen evolution potential at +2·5 V in the vanadium redox battery solution. The suitable working temperature of disc working electrode was 35°C. The suitable scanning rate range of disc working electrode was 50–200 mV s−1.

In this paper, high-iron bauxite was reduced deeply using natural gas as reductant in a closed circulation reduction furnace and then it was disposed by ball milling and magnetic separation. The results of study showed: when the optimum conditions of reduction of high-iron bauxite were that a temperature of 900°C, a reaction time of 120 min and a material thickness of 5 mm, iron powder and carbon black can be obtained, the particle size of iron powder was about 50∼200 nm, and the carbon black was about 30∼100 nm.