Primeiro registro de Rachiplusia nu (Guenée, 1852) (Lepidoptera: Noctuidae) sobrevivendo em soja Bt no Brasil

Loopers are important defoliators in several crop species. Among the loopers attacking non-Bt soybean cultivars, Chrysodeixis includens (Walker, [1858]) was the most common. The use of trangenic Bt soybean in appromately 70% of the soybean fields in Brazil led to a decrease in the loopers in these fields. However, technical field specialists and soybean producers recently observed Plusiinae larvae damaging transgenic Bt soybean, posing a risk over the Bt technology. Therefore, the aim of this study was to identify and confirm the catterpillar species feeding on transgenic Bt soybean fields in Brazil. Larvae and soybean leaf samples were collected in 12 soybean-producing locations from four Brazillian States. Soybean leaf samples were tested to confirm whether they were transgenic Bt. Larvae were reared in artificial diet and submitted to feeding trials on non-transgenic and transgenic Bt soybean leaves. The species identification was perfomed by amplicon sequencing of the cytochrome oxidase I (COI) gene of eight larvae per local. All 12 populations fed in the transgenic Bt soybean and the sequencing analysis of COI determined that they belong to Rachiplusia nu (Guenée, 1852) with 100% similarity to the COI sequences available in NCBI for this species. These results suggest that the R. nu species is not controlled by the genetic modification event present in the tested soybean variety and highlights the need for additional looper management control strategies, such as insecticide application, for controlling this insect pest in transgenic Bt soybean.

Download Full-text

Genetic variability and population structure of Leucinodes orbonalis (Guenée), a severe insect pest of brinjal in India

Journal of Environmental Biology ◽

10.22438/jeb/43/1/mrn-1868 ◽

2022 ◽

Vol 43 (1) ◽

pp. 59-65

Author(s):

K.G. Padwal ◽

◽

S. Chakravarty ◽

C.P. Srivastava ◽

◽

...

Keyword(s):

Genetic Variation ◽

Insect Pest ◽

Geographical Location ◽

Pcr Amplification ◽

Haplotype Network ◽

Coi Gene ◽

Sequence Alignments ◽

Multiple Sequence ◽

Leucinodes Orbonalis ◽

Coi Sequences

Aim: The present study was undertaken to provide valuable insights regarding population genetic structure of Leucinodes orbonalis from diverse agro-ecologies of India. Methodology: Molecular characterization of L. orbonalis populations collected from five major agro-climatic zones of India was carried out using mitochondrial cytochrome oxidase I (COI) gene. Collected specimens were subjected to DNA extractions, partial PCR amplification and sequencing of the target gene, and multiple sequence alignments. Results: The results showed very less diversity in the nucleotide positions of the COI sequences of 79 studied specimens, with a low number of segregating sites (30), nucleotide diversity (0.00438) and overall mean genetic distance (0.004 ± 0.001). The significant negative values of neutrality tests and unimodal mismatch distribution supported the demographic expansion theory in Indian L. orbonalis. Analysis of the molecular variance revealed that 93.13% of the genetic variation was within populations, and the variation among populations was only 6.87%. The pairwise genetic differentiation was also found to be low to moderate between most of the populations. Multiple haplotypes were recorded from all the populations, and both neighbour-joining tree as well as the haplotype network showed that clustering of the haplotypes was independent of the geographical location. Interpretation: Thus, it can be inferred that Indian populations of L. orbonalis have very low genetic variation levels concerning the COI gene. There is a possible occurrence of stable inherited gene flow among populations, thereby reducing genetic variation in India.

Download Full-text

Investigating the Parasitoid Community Associated with the Invasive Mealybug Phenacoccus solenopsis in Southern China

Insects ◽

10.3390/insects12040290 ◽

2021 ◽

Vol 12 (4) ◽

pp. 290

Author(s):

Hua-Yan Chen ◽

Hong-Liang Li ◽

Hong Pang ◽

Chao-Dong Zhu ◽

Yan-Zhou Zhang

Keyword(s):

Biological Control ◽

Species Delimitation ◽

Southern China ◽

Insect Pest ◽

Integrated Approach ◽

Molecular Data ◽

Coi Gene ◽

Morphological Examination ◽

Accurate Identification ◽

Phenacoccus Solenopsis

The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), is an emerging invasive insect pest in China. Hymenopteran parasitoids are the key organisms for suppressing populations of P. solenopsis in the field, and therefore could be used as biological agents. Accurate identification of the associated parasitoids is the critical step to assess their potential role in biological control. In this study, we facilitated the identification of the parasitoid composition of P. solenopsis using an integrated approach of species delimitation, combining morphology with molecular data. Eighteen Hymenoptera parasitoid species belonging to 11 genera of four families are recognized based on morphological examination and molecular species delimitation of the mitochondrial cytochrome c oxidase 1 (COI) gene and the 28S rDNA using the automatic barcode gap discovery (ABGD) and the Bayesian Poisson tree processes model (bPTP). Among these species, eight species are primary parasitoids with Aenasius arizonensis (Girault) (Hymenoptera: Encyrtidae) being the dominant taxon, while the other 10 species are probably hyperparasitoids, with a prevalence of Cheiloneurus nankingensis Li & Xu (Hymenoptera: Encyrtidae). These results indicate that parasitoid wasps associated with P. solenopsis from China are diverse and the integrated taxonomic approach applied in this study could enhance the accurate identification of these parasitoids that should be assessed in future biological control programs.

Download Full-text

Chemosensory genes in the head of Spodoptera litura larvae

Bulletin of Entomological Research ◽

10.1017/s0007485321000109 ◽

2021 ◽

pp. 1-10

Author(s):

Lu-Lu Li ◽

Ji-Wei Xu ◽

Wei-Chen Yao ◽

Hui-Hui Yang ◽

Youssef Dewer ◽

...

Keyword(s):

Spodoptera Litura ◽

Phylogenetic Trees ◽

Target Genes ◽

Control Strategies ◽

Insect Pest ◽

Management Strategies ◽

Food Sources ◽

Larval Feeding ◽

Chemosensory System ◽

Chemosensory Genes

Abstract The tobacco cutworm Spodoptera litura (Lepidoptera: Noctuidae) is a polyphagous pest with a highly selective and sensitive chemosensory system involved in complex physiological behaviors such as searching for food sources, feeding, courtship, and oviposition. However, effective management strategies for controlling the insect pest populations under threshold levels are lacking. Therefore, there is an urgent need to formulate eco-friendly pest control strategies based on the disruption of the insect chemosensory system. In this study, we identified 158 putative chemosensory genes based on transcriptomic and genomic data for S. litura, including 45 odorant-binding proteins (OBPs, nine were new), 23 chemosensory proteins (CSPs), 60 odorant receptors (ORs, three were new), and 30 gustatory receptors (GRs, three were new), a number higher than those reported by previous transcriptome studies. Subsequently, we constructed phylogenetic trees based on these genes in moths and analyzed the dynamic expression of various genes in head capsules across larval instars using quantitative real-time polymerase chain reaction. Nine genes–SlitOBP8, SlitOBP9, SlitOBP25, SlitCSP1, SlitCSP7, SlitCSP18, SlitOR34, SlitGR240, and SlitGR242–were highly expressed in the heads of 3- to 5-day-old S. litura larvae. The genes differentially expressed in olfactory organs during larval development might play crucial roles in the chemosensory system of S. litura larvae. Our findings substantially expand the gene inventory for S. litura and present potential target genes for further studies on larval feeding in S. litura.

Download Full-text

Haplotype-resolved genome assembly enables gene discovery in the red palm weevil Rhynchophorus ferrugineus

Scientific Reports ◽

10.1038/s41598-021-89091-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Guilherme B. Dias ◽

Musaad A. Altammami ◽

Hamadttu A. F. El-Shafie ◽

Fahad M. Alhoshani ◽

Mohamed B. Al-Fageeh ◽

...

Keyword(s):

Genome Assembly ◽

Control Strategies ◽

Insect Pest ◽

Single Copy ◽

Gene Content ◽

Rhynchophorus Ferrugineus ◽

Red Palm Weevil ◽

Transcriptomic Data ◽

Palm Trees ◽

Palm Weevil

AbstractThe red palm weevil Rhynchophorus ferrugineus (Coleoptera: Curculionidae) is an economically-important invasive species that attacks multiple species of palm trees around the world. A better understanding of gene content and function in R. ferrugineus has the potential to inform pest control strategies and thereby mitigate economic and biodiversity losses caused by this species. Using 10x Genomics linked-read sequencing, we produced a haplotype-resolved diploid genome assembly for R. ferrugineus from a single heterozygous individual with modest sequencing coverage ($$\sim$$ ∼ 62x). Benchmarking against conserved single-copy Arthropod orthologs suggests both pseudo-haplotypes in our R. ferrugineus genome assembly are highly complete with respect to gene content, and do not suffer from haplotype-induced duplication artifacts present in a recently published hybrid assembly for this species. Annotation of the larger pseudo-haplotype in our assembly provides evidence for 23,413 protein-coding loci in R. ferrugineus, including over 13,000 predicted proteins annotated with Gene Ontology terms and over 6000 loci independently supported by high-quality Iso-Seq transcriptomic data. Our assembly also includes 95% of R. ferrugineus chemosensory, detoxification and neuropeptide-related transcripts identified previously using RNA-seq transcriptomic data, and provides a platform for the molecular analysis of these and other functionally-relevant genes that can help guide management of this widespread insect pest.

Download Full-text

Study and Simulation on the Energy Efficiency Management Control Strategy of Ship Based on Clean Propulsion System

Volume 7: Ocean Engineering ◽

10.1115/omae2015-41597 ◽

2015 ◽

Cited By ~ 1

Author(s):

Kai Wang ◽

Xinping Yan ◽

Yupeng Yuan

Keyword(s):

Energy Efficiency ◽

Energy Consumption ◽

Control Strategy ◽

Control Strategies ◽

Management Control ◽

Propulsion System ◽

Power Requirement ◽

Doubly Fed ◽

System Configurations ◽

And Control

Nowadays, with the higher voice of ship energy saving and emission reduction, the research on energy efficiency management is particularly necessary. Energy efficiency management and control of ships is an effective way to improve the ship energy efficiency. In this paper, according to the new clean propulsion system configurations of 5000 tons of bulk carrier, the energy efficiency management control strategy of the clean propulsion system is designed based on the model of advanced brushless doubly-fed shaft generator, propulsion system using LNG/diesel dual fuel engine and energy consumption of the main engine for reducing energy consumption. The simulation model of the entire propulsion system and the designed control strategy were designed. The influence of the engine speed on the ship energy efficiency was analyzed, and the feasibility of the energy efficiency management control strategies was verified by simulation using Matlab/Simulink. The results show that the designed strategies can ensure the power requirement of the whole ship under different conditions and improve the ship energy efficiency and reduce CO2 emissions.

Download Full-text

Repellency Mechanism of Natural Guar Gum-Based Film Incorporated with Citral against Brown Planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae)

International Journal of Molecular Sciences ◽

10.3390/ijms23020758 ◽

2022 ◽

Vol 23 (2) ◽

pp. 758

Author(s):

Xiubing Gao ◽

Xianfeng Hu ◽

Feixu Mo ◽

Yi Ding ◽

Ming Li ◽

...

Keyword(s):

Differential Expression ◽

Guar Gum ◽

Defense Mechanism ◽

Insect Pests ◽

Odorant Receptor ◽

Receptor Gene ◽

Insect Pest ◽

Brown Planthopper ◽

Sequencing Analysis ◽

Or Gene

Using of plant essential oil that coevolved as a defense mechanism against agriculture insects is an alternative means of controlling many insect pests. In order to repel brown planthoppers (BPHs), the most notorious rice insect pest, a new film based on guar gum incorporated with citral (GC film) was formulated, which was effective while being environmentally friendly. In this paper, the effect and mechanism of GC film repellency against BPHs were determined. Repellent activity test and olfactory reaction analysis showed that GC film had repellency effect against BPHs, with repellency of 60.00% and 73.93%, respectively. The result of olfactory reaction indicated that GC film repellency against BPHs relied on smell. EPG analysis showed the proportion and mean duration of np waveform were significantly higher than in CK and increased following the treatment concentration, which indicated that GC film affected the recognition of BPHs to rice. Further analysis by RNA sequencing analysis showed a total of 679 genes were significantly upregulated and 284 genes were significantly downregulated in the BPHs fed on the rice sprayed with GC film compared to control. Odorant-binding protein (OBP) gene 797 and gustatory receptor gene (GR)/odorant receptor (OR) gene 13110 showed a significant decrease in differential expression and significant increase in differential expression, respectively. There were 0.66 and 2.55 differential expression multiples between treated BPHs and control, respectively. According to the results described above, we reasoned that GC film repellency against BPHs due to smell, by release of citral, caused the recognition difficulties for BPHs to rice, and OBP gene 797 and GR/OR gene 13110 appeared to be the crucial candidate genes for GC film repellency against BPHs. The present study depicted a clear and consistent repellency effect for GC film against BPHs and preliminarily clarified the mechanism of GC film as a repellent against BPHs, which might offer an alternative approach for control of BPHs in the near future. Our results could also help in the development and improvement of GC films.

Download Full-text

Workstation benchmark of Spark Capable Genome Analysis ToolKit 4 Variant Calling

10.1101/2020.05.17.101105 ◽

2020 ◽

Author(s):

Marcus H. Hansen ◽

Anita T. Simonsen ◽

Hans B. Ommen ◽

Charlotte G. Nyvold

Keyword(s):

Dna Sequencing ◽

Genome Analysis ◽

High Speed ◽

High Performance ◽

Variant Calling ◽

Amplicon Sequencing ◽

Targeted Sequencing ◽

Sequencing Analysis ◽

Genome Analysis Toolkit ◽

Order Of Magnitude

AbstractBackgroundRapid and practical DNA-sequencing processing has become essential for modern biomedical laboratories, especially in the field of cancer, pathology and genetics. While sequencing turn-over time has been, and still is, a bottleneck in research and diagnostics, the field of bioinformatics is moving at a rapid pace – both in terms of hardware and software development. Here, we benchmarked the local performance of three of the most important Spark-enabled Genome analysis toolkit 4 (GATK4) tools in a targeted sequencing workflow: Duplicate marking, base quality score recalibration (BQSR) and variant calling on targeted DNA sequencing using a modest hyperthreading 12-core single CPU and a high-speed PCI express solid-state drive.ResultsCompared to the previous GATK version the performance of Spark-enabled BQSR and HaplotypeCaller is shifted towards a more efficient usage of the available cores on CPU and outperforms the earlier GATK3.8 version with an order of magnitude reduction in processing time to analysis ready variants, whereas MarkDuplicateSpark was found to be thrice as fast. Furthermore, HaploTypeCallerSpark and BQSRPipelineSpark were significantly faster than the equivalent GATK4 standard tools with a combined ∼86% reduction in execution time, reaching a median rate of ten million processed bases per second, and duplicate marking was reduced ∼42%. The called variants were found to be in close agreement between the Spark and non-Spark versions, with an overall concordance of 98%. In this setup, the tools were also highly efficient when compared execution on a small 72 virtual CPU/18-node Google Cloud cluster.ConclusionIn conclusion, GATK4 offers practical parallelization possibilities for DNA sequence processing, and the Spark-enabled tools optimize performance and utilization of local CPUs. Spark utilizing GATK variant calling is several times faster than previous GATK3.8 multithreading with the same multi-core, single CPU, configuration. The improved opportunities for parallel computations not only hold implications for high-performance cluster, but also for modest laboratory or research workstations for targeted sequencing analysis, such as exome, panel or amplicon sequencing.

Download Full-text

Effects of Different Water Regimes and Spacing on Insect Pest Infestation and Efficacy of Control Measures in Cucumber (Cucumis sativus)

Journal of Experimental Agriculture International ◽

10.9734/jeai/2019/v41i530415 ◽

2019 ◽

pp. 1-8

Author(s):

A. A. Oso ◽

G. O. Awe

Keyword(s):

Integrated Pest Management ◽

Pest Management ◽

Pest Control ◽

Control Strategies ◽

Insect Pest ◽

Cultural Control ◽

Irrigated Agriculture ◽

Yield Attributes ◽

Pest Infestation ◽

And Control

Aim: Information on the influence of water availability during different seasons of rainfed or irrigated agriculture as it relates to insect pest population build-up in crops could assist in the development of integrated pest management. A study was therefore conducted to investigate effects of spacing, pest infestation and control on cucumber under rainfed and irrigated conditions. Place and Duration of Study: At the Teaching and Research Farm, Ekiti State University, Ado Ekiti, Nigeria during the 2016/2017 rainy and dry seasons. Methodology: The experiment was laid out using randomized complete block design (RCBD) in a split-plot arrangement in five replications, with spacing (60 x 60 cm, 60 x 90 cm and 60 x 120 cm) as the main plot treatments and the sub-plot treatments were different pest control strategies. The pest control strategies include synthetic insecticide (Lambda-cyhalothrin), botanical insecticide (Anogeissus leiocarpus) and control. Growth parameters and yield attributes were recorded. Insect pest occurrence, their build-up and percentage infestation on cucumber and the efficacy of the management strategies were monitored. Results: The results showed that yield was enhanced in irrigated system with the widest spacing of 60 x 120 cm botanical treatment interaction. Bemisia tabaci was the most prominent insect pest attacking cucumber under irrigated system. Conclusion: Other cultural control practices such as the use of trap crops with little or no financial implication should also be added to botanical pesticides as an integrated pest management tactic for effective management and control of the pest.

Download Full-text

First results of Central Asiatic Euchalcia DNA-studies: comparison of nucleotide sequence differences in COI between Euchalcia herrichi and Euchalcia gyulai (Lepidoptera: Noctuidae)

Acta Biologica Sibirica ◽

10.3897/abs.6.e52836 ◽

2020 ◽

Vol 6 ◽

pp. 1-4

Author(s):

Stanislav K Korb

Keyword(s):

Nucleotide Sequence ◽

Cytochrome C ◽

Dna Barcoding ◽

Cytochrome C Oxidase ◽

Coi Gene ◽

First Results ◽

The Difference ◽

Coi Sequences ◽

Lepidoptera Noctuidae ◽

Two Populations

We submitted first results of the DNA studies of the Central Asiatic owlet moths of the genus Euchalcia. Standard cytochrome C oxidase subunit I (COI) gene fragments were sequenced for DNA barcoding of six specimens belonging to Euchalcia herrichi and Euchalcia gyulai. We compared the received sequences between discussed species and with two European Euchalcia species (E. variabilis and E. consona). We found no variability within the COI sequences of the samples collected in the same locality (Alai Mts., Kyrgyzstan), whereas the difference in COI sequences between two populations (Ketmen Mts., Kazakhstan and Alai Mts., Kyrgyzstan) was 0.005.

Download Full-text

Monitoring Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) Infestation in Soybean Using Hyperspectral Remote Sensing

10.20944/preprints202010.0229.v1 ◽

2020 ◽

Author(s):

Pedro P. S. Barros ◽

Inana X. Schutze ◽

Fernando H. Iost Filho ◽

Pedro Takao Yamamoto ◽

Peterson Fiorio ◽

...

Keyword(s):

Remote Sensing ◽

Bemisia Tabaci ◽

Insect Pest ◽

Remote Sensing Data ◽

Management Program ◽

Hyperspectral Remote Sensing ◽

Negative Effects ◽

Soybean Plants ◽

Soybean Leaves ◽

Different Levels

Although monitoring and observing insect pest populations in the fields is essential in crop management, it is still a laborious and sometimes ineffective process. High infestation levels may diminish the photosynthetic activity of soybean plants, affecting their development and reducing the yield. An imprecise decision making in integrated pest management program may lead to an ineffective control in infested areas or the excessive use of insecticides. In order to reach a more efficient control of arthropods population it is important to evaluate the infestation in time to mitigate its negative effects on the crop and remote sensing is an important tool for monitoring. It was proposed that infested soybean areas could be identified, and the arthropods quantified from non-infested areas in a field by hyperspectral remote sensing. Thus, the goals of this study were to investigate and discriminate the reflectance characteristics of soybean non-infested and infested with Bemisia tabaci using hyperspectral remote sensing data. Therefore, samples of infested and non-infested soybean leaves were collected and transported to the laboratory to obtain the hyperspectral curves. The results obtained allowed to discriminate the different levels of infestation and to separate healthy from whitefly infested soybean leaves based on their reflectance.

Download Full-text