Comparative hemolymph proteomic analyses of the freezing and resistance-freezing Ostrinia furnacalis (Guenée).

The Asian corn borer, Ostrinia furnacalis (Guenée) (Lepidoptera: Crambidae), is one of the most harmful pests of maize in Asia. It poses a significant threat to maize production, causing economic losses due to its strong ecological adaptation. In this study, we compared and analyzed the hemolymph proteome between freezing and resistance-freezing O. furnacalis strains using two-dimensional gel electrophoresis to gain insights into the mechanisms of cold resistance. The results revealed that 300-400 hemolymph protein spots were common, with 24 spots showing differences between the two strains. Spectrometry analysis revealed 21 protein spots, including 17 upregulated spots and 4 downregulated ones. The expression of upregulation/downregulation proteins plays a crucial role in the metabolism, energy supply, and defense reaction of insects. Proteomics research not only provides a method for investigating protein expression patterns but also identifies numerous attractive candidates for further exploration.

High-Performance Hydrogen Evolution Reaction Catalytic Electrodes by Liquid Joule-Heating Growth.

Despite the great progress in the research of integrated catalytic electrodes for hydrogen evolution reaction, the efficient preparation of high-performance catalytic electrodes with high current density remains a challenging issue. In this work, a metal (Pt)-amorphous oxide (NiO) heterostructure catalyst is successfully in situ grown on nickel foam using liquid Joule-heating. Based on the superhydrophilic surface of the electrode and its superior mechanical and chemical stability, the catalytic electrode exhibits excellent catalytic performance in alkaline electrolytes with only 100 mV overpotential to achieve 5000 mA cm-2 current density and maintains a stable performance of 500 h under a fixed current density of 1000 mA cm-2 . Further verification of the practical application of the Pt@NiO-Ni electrode in the alkaline electrolyzer is conducted. The results show that the alkaline water electrolyzer with NiFe layered double hydroxide as the anode and Pt@NiO-Ni as the cathode exhibits superior performance than the previously reported electrolyzers, with a current density of 1 A cm-2 already achieved at 1.75 V, which is even comparable to some anion exchange membrane water electrolyzers. These experimental results illustrate the strong applicability of Pt@NiO-Ni electrode at industrial scale current densities.

Population Genomics Provide Insights into the Evolution and Adaptation of the Asia Corn Borer.

Understanding the genetic basis of pest adaptive evolution and the risk of adaptation in response to climate change is essential for the development of sustainable agricultural practices. However, the genetic basis of climatic adaptation for the Asian corn borer (ACB), Ostrinia furnacalis, the main pest of corn in Asia and Oceania, is poorly understood. Here, we revealed the genomic loci underlying the climatic adaptation and evolution in ACB by integrating population genomic and environmental factors. We assembled a 471-Mb chromosome-scale reference genome of ACB and resequenced 423 individuals covering 27 representative geographic areas. We inferred that the ACB effective population size changes tracked with the global temperature and followed by a recent decline. Based on an integrated analysis of whole-genome selection scans and genome-wide genotype-environment association studies, we revealed the genetic basis of ACB adaption to diverse climates. For diapause traits, we identified a major effect association locus containing a circadian clock gene (period) by analyzing a diapause-segregating population. Moreover, our predictions indicated that the northern populations were more ecologically resilient to climate change than the southern populations. Together, our results revealed the genomic basis for ACB environmental adaptation and provided potential candidate genes for future evolutionary studies and genetic adaptation to climate change, intending to maintain the efficacy and sustainability of novel control techniques.

First Report of Botryosphaeria dothidea Causing Leaf Spot on Kadsura coccinea in China.

Kadsura coccinea (Lem.) A. C. Smith, belonging to Schisandraceae, is an evergreen, woody climbing plant that is distributed widely in southwest China. Additionally, K.coccinea is used as an ethnic medicine and its main chemical components are lignin and terpenoids. The roots of the plant have been effectively used for treatment of cancer and dermatosis and as an anodyne to relieve pain (Song et al. 2010). In June 2019, a leaf spot disease on K. coccinea was first observed in a greenhouse in Qiandongnan Miao and Dong Autonomous Prefecture, Guizhou Province, China. Over 300 plants were surveyed in the three greenhouses, and nearly 70% of the plants were infected. The diseased plants grew poorly and appeared stunted, and severely affected plants died. The symptoms occurred on leaves as small brown spots initially and then developed into suborbicular or irregular-shaped brown necrotic lesions, which often displayed irregular concentric rings. Four diseased leaves from four symptomatic Kadsura coccinea plants were randomly collected for pathogen isolation. Diseased tissues were cut into about 2mm diameter fragments, surface sterilized with 75% ethanol for 15 s and 1% NaClO for 2 min, and then rinsed twice in sterilized distilled water. After being dried on sterilized filter paper, the fragments were placed on potato dextrose agar (PDA) and incubated at 25°C in the dark for 5 days. The same fungus was isolated in 95% of the samples. A representative isolate, F2020003 was used for morphological and molecular characterization. The colonies were initially white, gradually turning gray-green to dark gray after 7 days, with abundant gray aerial mycelium. Conidia were one-celled, hyaline, fusoid to ellipsoid and measured 24.3 ± 1.9 × 4.8 ± 0.7 µm (n = 50). The conidial morphology matched the description of Botryosphaeria dothidea (Slippers et al. 2004). To verify identity, the partial sequences of the internal transcribed spacer region, translation elongation factor 1 alpha genes and beta-tubulin, were amplified from isolate F2020003 with primers ITS1/ITS4 (GenBank accession no. MW111267), EF1-728F/EF1-986R (GenBank accession no. MW196739) and BT-2a/BT-2b (GenBank accession no. MW206378), respectively（Sun et al. 2014）. The isolates were confirmed as B. dothidea based on morphological comparisons and BLAST searches (Zhai et al. 2014). To assess pathogenicity, five healthy leaves on each of the three 6-month-old healthy K. coccinea plants were wound inoculated with a sterilized needle. Mycelium plugs (4 mm in diameter) taken from a 5-day-old culture on PDA were inoculated on surface-sterilized leaves (sprayed with 75% ethanol). PDA plugs with no mycelium were used as a control. Plants with treated leaves were covered with plastic bags and incubated in a greenhouse at 25°C. The pathogenicity test was repeated three times. Within 4 days, all the inoculated points showed lesions similar to those previously observed in the greenhouse, whereas controls were asymptomatic. Fungi re-isolated from inoculated leaves were confirmed as B. dothidea on the basis of morphological and molecular characterization as described above. B. dothidea is a member of Botryosphaeriaceae, it has been reported to cause leaf spot on Celtis sinensis (Wang et al., 2020) and branch canker on Malosma laurina (Aguirre et al., 2018) in China. To our knowledge, this is the first report of B. dothidea causing leaf spot on K. coccinea in China. The identification of this pathogen will be helpful to prevent and control this disease in the future.

The complete mitochondrial genome of Corythoxestis sunosei (Lepidoptera: Gracillariidae) with phylogenetic consideration.

The complete mitogenome of Corythoxestis sunosei (GenBank accession number MT611524) is 15,511 bp in length, and harbors 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes, and an A + T-rich region. The overall base composition is A (40.04%), C (10.64%), G (7.62%), and T (41.70%), showing AT-rich feature (81.74%). ATG, ATT, CGA were initiation codons and TAA and T were termination codons. All the 22 tRNAs displayed a common cloverleaf secondary structure, except for trnS1 which lacked the dihydrouracil (DHU) arm. Phylogenetic tree based on 13 PCGs showed that C. sunosei has a close phylogenetic relationship with Gibbovalva kobusi and Cameraria ohridella and belongs to Gracillariidae.

Genetic variation and geographic differentiation among populations of the nonmigratory agricultural pest Oedaleus infernalis (Orthoptera: Acridoidea) in China.

The nonmigratory grasshopper Oedaleus infernalis Saussure (Orthoptera : Acridoidea) is an agricultural pest to crops and forage grasses over a wide natural geographical distribution in China. The genetic diversity and genetic variation among 10 geographically separated populations of O. infernalis was assessed using polymerase chain reaction-based molecular markers, including the intersimple sequence repeat and mitochondrial cytochrome oxidase sequences. A high level of genetic diversity was detected among these populations from the intersimple sequence repeat (H: 0.2628, I: 0.4129, Hs: 0.2130) and cytochrome oxidase analyses (Hd: 0.653). There was no obvious geographical structure based on an unweighted pair group method analysis and median-joining network. The values of FST, θ(II), and Gst estimated in this study are low, and the gene flow is high (Nm > 4). Analysis of the molecular variance suggested that most of the genetic variation occurs within populations, whereas only a small variation takes place between populations. No significant correlation was found between the genetic distance and geographical distance. Overall, our results suggest that the geographical distance plays an unimpeded role in the gene flow among O. infernalis populations.