Populations Of Plutella Xylostella Research Articles

Key Contributions of the Overexpressed Plutella xylostella Sigma Glutathione S-Transferase 1 Gene (PxGSTs1) in the Resistance Evolution to Multiple Insecticides.

The overexpression of insect detoxification enzymes is a typical adaptive evolutionary strategy for insects to cope with insecticide pressure. In this study, we identified a glutathione S-transferase (GST) gene, PxGSTs1, that exhibited pronounced expression in the field-resistant population of Plutella xylostella. By using RNAi (RNA interference), the transgenic fly models, and quantitative real-time polymerase chain reaction (RT-qPCR) methods, we confirmed that the augmented expression of PxGSTs1 mediates the resistance of P. xylostella to various types of insecticides, including chlorantraniliprole, novaluron, λ-cyhalothrin, and abamectin. PxGSTs1 was found to bolster insecticide resistance in two ways: direct detoxification and enhancing antioxidative defenses. In addition, our findings demonstrated that pxy-miR-8528a exerts a pivotal influence on forming insecticide resistance in P. xylostella by downregulating PxGSTs1 expression. In summary, we elucidated the multifaceted molecular and biochemical underpinnings of PxGSTs1-driven insecticide resistance in P. xylostella. Our results provide a new perspective for understanding the insecticide resistance mechanism of P. xylostella.

High resistance levels in brazilian Plutella xylostella populations: needs for adjustments in field concentration

ABSTRACT Plutella xylostella cause severe damage on cruciferous plants all over the world. Farmers in several regions of Brazil report increasing inefficiency of chemical control, even when using high insecticide concentrations. We evaluate here the susceptibility of brazilian diamondback moth populations to the Premio® (Chlorantraniliprole), Dipel® (Bacillus thuringiensis var. kurstaki) and Lannate® BR (Oxime Methylcarbamate) insecticides, frequently used in Brazil. Susceptibility bioassays with five field-collected and two laboratory diamondback moth populations were conducted with increasing concentrations of insecticides up to ten times above the recommended concentration. Extremely high and region-dependent resistances were found in field populations against Chlorantraniliprole and B. thuringiensis, with Resistance Ratios up to 370.0 times for the Camocim de São Felix population. For Oxime Methylcarbamate, we were not able to do Probit analyses for the field populations because of very low mortality rates. Laboratory populations showed resistance to the three tested insecticides with all LC50 concentrations exceeding the recommended doses by at least 3 times. Our results show strong and variable resistance to the three tested insecticides according to the region of origin. To maintain efficient pest control in a large country like Brazil, local levels of resistance need therefore to be monitored by the authorities and reassessment and adjustments of regional doses of insecticides should be implemented as a public policy, to prevent massive spread of insecticides in the field, as well as increases in cases of resistance.

Deciphering the Molecular Mechanisms of Insecticide Resistance From the Transcriptome Data of Field Evolved Spinosad Resistant and Susceptible Populations of Plutella xylostella (Lepidoptera: Plutellidae).

Diamondback moth, Plutella xylostella is a serious pest of cruciferous vegetables and causes substantial economic loss all over the world. This study was undertaken to decipher the molecular mechanisms involved in the field evolved insecticide resistance in P. xylostella upon exposure to spinosad. To do so, spinosad-resistant and susceptible larval populations were subjected to transcriptome analysis using Illumina paired-end sequencing. De novo assembly was generated from raw reads of both the samples which resulted in the identification of 41,205 unigenes. Functional annotation and digital gene expression analysis were carried out to determine the differentially expressed genes. 1,348 unigenes were found to have a significant differential expression in the resistant population. Several genes involved in insecticide resistance like CYP P450, GSTs, small heat shock protein, and UDP glycosyltransferase were found to be up-regulated while genes related to mitochondrial energy metabolism and cuticular processes were down-regulated. Further, gene mining and phylogenetic analysis of two important gene families namely, CYP and GSTs were performed and the results revealed that these genes could play a major role in the development of field evolved spinosad resistance in P. xylostella by gene duplication and differential gene expression.

Susceptibility of Plutella xylostella (L.) to Bacillus thuringiensis Berliner strains

The objective was to observe the susceptibility of a population of Plutella xylostella (L.) maintained for 100 generations in laboratory to strains of Bacillus thuringiensis Berliner. The concentrations 9×104, 1.5×105, 6×105, 8×105, 9×105, 1.5×106, 2×106, 3×106, 4.5×106, 6×106, 7.5×106, 9×106, 1.5×107, 2×107, 3×107, 4×107, 4.5×107, 6×107, 7.5×107, 9.5×107, 1.5×108 e 3×108 spores/mL were evaluated for the strains: E1, 49.30A, E2, 1.7L, T3A.259, T3A.140, T08024, E26, E22 and T07. The strains E26, E22 and T07 did not cause mortality for P. xylostella larvae. The P. xylostella larvae have a very high susceptibility pattern to the concentrations evaluated for six strains tested (E1, 49.30A, E2, 1.7L, T3A.259 and T3A.140). Only the T08.024 strain allowed the estimation of lethal concentration that kills 50% of the population (2.7 spores/mL).

Brassica patch geometry and adjacent matrix: how small-scale changes in landscape can affect Plutella xylostella populations

Herbivorous insects are predicted to have higher densities in larger patches, while their natural enemies will be more affected by the edge of these patches. In this paper, we investigate the effect of the relationship between brassica horticultural plot shape and the adjacent land use on the abundance of P. xylostella and its chances to be parasitised. Samples were collected from brassica plots during spring. Landscape metrics of the study area were estimated using Landsat images. We found a negative relationship between the pest abundance and the perimeter-to-area ratio of the brassica plot, and a positive relationship with land cover estimated from Landsat images. The proportion of parasitised immatures showed opposite relationship with the same variables. Implications of these findings are discussed.

Influence of temperature on spinosad toxicity in different populations of Plutella xylostella (Linnaeus)


 Diamond back moth, Plutella xylostella (Linnaeus) is one of the major insect-pest of cole crops, causing high yield losses. In present study, larval populations of P. xylostella, collected from different regions of Punjab i.e. Amritsar, Kapurthala, Malerkotla and Ludhiana were exposed to different concentrations of spinosad at 15, 20, 25 and 30 °C for evaluation of LC values. The LC (Lethal 50 50 concentration) increased from lower (15 °C) to higher (30 °C) temperature for all populations of P. xylostella. Negative correlation was observed between the temperature coefficient and toxicity of spinosad towards P. xylostella populations, which decreased with increase in temperature. The LC 50 values varied among different populations of P. xylostella i.e. Amritsar populations with higher LC values 50 followed by Kapurthala, Malerkotla and Ludhiana populations. The temperature and insecticide exposure history both affected the toxicity of spinosad for P. xylostella. The information would be helpful in developing management strategies for P. xylostella according to prevailing environment conditions.

Regulation of GSTu1-mediated insecticide resistance in Plutella xylostella by miRNA and lncRNA.

The evolution of resistance to insecticides is well known to be closely associated with the overexpression of detoxifying enzymes. Although the role of glutathione S-transferase (GST) genes in insecticide resistance has been widely reported, the underlying regulatory mechanisms are poorly understood. Here, one GST gene (GSTu1) and its antisense transcript (lnc-GSTu1-AS) were identified and cloned, and both of them were upregulated in several chlorantraniliprole-resistant Plutella xylostella populations. GSTu1 was confirmed to be involved in chlorantraniliprole resistance by direct degradation of this insecticide. Furthermore, we demonstrated that lnc-GSTu1-AS interacted with GSTu1 by forming an RNA duplex, which masked the binding site of miR-8525-5p at the GSTu1-3′UTR. In summary, we revealed that lnc-GSTu1-AS maintained the mRNA stability of GSTu1 by preventing its degradation that could have been induced by miR-8525-5p and thus increased the resistance of P. xylostella to chlorantraniliprole. Our findings reveal a new noncoding RNA-mediated pathway that regulates the expression of detoxifying enzymes in insecticide-resistant insects and offer opportunities for the further understanding of the mechanisms of insecticide and drug resistance.

Comparative Transcriptome Analysis Reveals Sex-Based Differences during the Development of the Adult Parasitic Wasp Cotesia vestalis (Hymenoptera: Braconidae).

The endoparasitic wasp Cotesia vestalis is an important biological agent for controlling the population of Plutella xylostella, a major pest of cruciferous crops worldwide. Though the genome of C. vestalis has recently been reported, molecular mechanisms associated with sexual development have not been comprehensively studied. Here, we combined PacBio Iso-Seq and Illumina RNA-Seq to perform genome-wide profiling of pharate adult and adult development of male and female C. vestalis. Taking advantage of Iso-Seq full-length reads, we identified 14,466 novel transcripts as well as 8770 lncRNAs, with many lncRNAs showing a sex- and stage-specific expression pattern. The differentially expressed gene (DEG) analyses showed 2125 stage-specific and 326 sex-specific expressed genes. We also found that 4819 genes showed 11,856 alternative splicing events through combining the Iso-Seq and RNA-Seq data. The results of comparative analyses showed that most genes were alternatively spliced across developmental stages, and alternative splicing (AS) events were more prevalent in females than in males. Furthermore, we identified six sex-determining genes in this parasitic wasp and verified their sex-specific alternative splicing profiles. Specifically, the characterization of feminizer and doublesex splicing between male and female implies a conserved regulation mechanism of sexual development in parasitic wasps.

Functional analysis of a carboxylesterase gene involved in beta-cypermethrin and phoxim resistance in Plutella xylostella (L.).

Carboxylesterases (CarEs) are associated with detoxification of xenobiotics, including insecticides, in organism bodies. Overexpression of CarE genes is considered to have an important role in insecticide resistance in insects, however its involvement in multi-insecticide resistance has rarely been reported. This study aimed to assess the function of a CarE gene (PxαE8) in resistance to five insecticides in Plutella xylostella. Relative expression of PxαE8 in three multi-insecticide-resistant Plutella xylostella populations, GD-2017, GD-2019 and HN, was14.8-, 19.5- and 28.0-fold higher than that in the susceptible population. Exposure to lethal concentrations associated with 25% mortality (LC25 ) of beta-cypermethrin, chlorantraniliprole, metaflumizone, phoxim and tebufenozide could induce the specific activity of CarEs and increase the relative expression of PxαE8. By contrast, knockdown of PxαE8 expression dramatically reduced the activity of CarEs and increased the resistance of P. xylostella (GD-2019) larvae to beta-cypermethrin and phoxim by 47.4% and 45.5%, respectively. Further, a transgenic line of Drosophila melanogaster overexpressing PxαE8 was constructed and the bioassay results showed that the tolerance of transgenic Drosophila to beta-cypermethrin and phoxim was 3.93- and 3.98-fold higher than that of the untransgenic line. These results provide evidence that overexpression of PxαE8 is involved in resistance, at least to beta-cypermethrin and phoxim, in multi-insecticide-resistant P. xylostella populations, which could help in further understanding the molecular mechanisms of multi-insecticide resistance in this pest. © 2020 Society of Chemical Industry.

Changes in the Biological Characteristics of Plutella xylostella Using Ethanolic Plant Extracts

The indiscriminate use of synthetic insecticides has led to the emergence of resistant populations of Plutella xylostella L. (Lepidoptera: Plutellidae), hindering its control and causing economic damage to brassica production. Thus, in order to seek control alternatives, this study aimed at assessing the bioactivity of the ethanolic extracts of Schinus terebinthifolius (Anacardiaceae), Annona coriacea (Annonaceae), Annona crassiflora (Annonaceae), and Serjania marginata (Sapindaceae) on the life cycle of P. xylostella. Cabbage leaf discs were immersed in the treatments at a concentration of 10 mg/mL and given daily to the larvae. Larval and pupal duration and survival, pupae weight, the longevity of males and females, number and survival of eggs, incubation period, and days of oviposition parameters were evaluated. All extracts differed significantly from the control in terms of larval and pupal duration, pupal survival, and pupae weight. All the extracts prolonged the larval and pupal period of P. xylostella. Only A. coriacea did not differ significantly from the control in terms of larval survival, and the highest larval mortality was observed in the treatment with S. marginata (50%). Pupal survival, pupae mass, oviposition period, and egg survival were reduced in all treatments with ethanolic extracts. The treatments with Annona and S. marginata species have reduced the number of eggs. Treatments with S. terebinthifolius and S. marginata have reduced the incubation time of eggs. Thus, the treatments with ethanolic plant extracts act on the life cycle of P. xylostella negatively impacting the biological parameters evaluated.

Differential Profiles of Gut Microbiota and Metabolites Associated with Host Shift of Plutella xylostella.

Evolutionary and ecological forces are important factors that shape gut microbial profiles in hosts, which can help insects adapt to different environments through modulating their metabolites. However, little is known about how gut microbes and metabolites are altered when lepidopteran pest species switch hosts. In the present study, using 16S-rDNA sequencing and mass spectrometry-based metabolomics, we analyzed the gut microbiota and metabolites of three populations of Plutella xylostella: one feeding on radish (PxR) and two feeding on peas (PxP; with PxP-1 and PxP-17 being the first and 17th generations after host shift from radish to peas, respectively). We found that the diversity of gut microbes in PxP-17 was significantly lower than those in PxR and PxP-1, which indicates a distinct change in gut microbiota after host shift. Kyoto Encyclopedia of Genes and Genomes analysis revealed that the functions of energy metabolism, signal transduction, and xenobiotics biodegradation and metabolism were increased in PxP-17, suggesting their potential roles in host adaptation. Metabolic profiling showed a significant difference in the abundance of gut metabolites between PxR and PxP-17, and significant correlations of gut bacteria with gut metabolites. These findings shed light on the interaction among plants, herbivores, and symbionts, and advance our understanding of host adaptation associated with gut bacteria and metabolic activities in P. xylostella.

Field survey of ryanodine receptor mutations (G4946E and I4790K) and their effects on biotic performance in the diamondback moth.

This study examined changes in the proportions of ryanodine receptor mutations (G4946E and I4790K) for Plutella xylostella populations in the field. Results show that the proportion of G4946E decreased during the survey years without diamide application and that insects with I4790K were observed less frequently during the survey period. This study also examined the biotic performances of diamide-resistant P. xylostella strains. The results show that the diamide-resistant strains exhibited hatchability, larval development, and fecundity equivalent to those of diamide-susceptible strains.

Variation in Performance and Resistance to Parasitism of Plutella xylostella Populations.

Two major ecological factors determine the fitness of an insect herbivore: the ability to overcome plant resistance strategies (bottom-up effects) and the ability to avoid or resist attack by natural enemies such as predators and parasitoids (top-down effects). In response to differences in selection pressure, variation may exist in host-plant adaptation and immunity against parasitism among populations of an insect herbivore. We investigated the variation in larval performance of six different Plutella xylostella populations originating from four continents when feeding on a native Dutch plant species, Brassica rapa. One of the used populations has successfully switched its host plant, and is now adapted to pea. In addition, we determined the resistance to attack by the endoparasitoid Diadegma semiclausum originating from the Netherlands (where it is also native) and measured parasitoid performance as a proxy for host resistance against parasitism. Pupal mortality, immature development times, and adult biomass of P. xylostella differed significantly across populations when feeding on the same host plant species. In addition, parasitism success differed in terms of parasitoid adult emergence and their biomass, but not their development times. Variation among natural populations of insects should be considered more when studying interactions between plants and insects up the food chain.

Identification of a nativeBacillus thuringiensisstrain from Sri Lanka active against Dipel-resistantPlutella xylostella

BackgroundBiopesticides based on strains of the bacterium Bacillus thuringiensis (Bt) are used globally for effective and environmentally friendly pest control. The most serious threat to the sustainable use of these microbial pesticides is the development of resistance on targeted pests. Populations of Plutella xylostella (diamondback moth) have evolved field resistance to Bt pesticides at diverse locations worldwide. Discovery of novel Bt strains with varied toxin profiles that overcome resistance is one of the strategies to increase sustainability of Bt pesticides against P. xylostella. In this study, we report isolation and characterization of a Bt strain named AB1 from Sri Lanka displaying toxicity towards larvae of P. xylostella resistant to the commercial Bt pesticide Dipel.MethodsStrains of Bt from diverse environments in Sri Lanka were evaluated for protein crystal production through Differential Interference Contrast (DIC) microscopic examination, and for insecticidal activity against P. xylostella in bioassays. The genome of the AB1 strain was sequenced by Hiseq Illumina sequencing to identify the insecticidal genes present in the genome and nano liquid chromatography followed by tandem mass spectrometry (nanoLC/MS/MS) of purified crystal proteins of AB1 was performed to identify the expressed insecticidal proteins. Multilocus sequence typing and Gyrase B gene sequence analyses were performed to identify the phylogenetic origin of the AB1 strain.ResultsThe AB1 strain was identified as producing high levels of bipyramidal crystals and displaying insecticidal activity against susceptible and Dipel-resistant strains of P. xylostella. Multilocus sequence typing and phylogenetic analysis of the Gyrase B gene identified that AB1 belongs to the B. thuringiensis subsp. aizawai serotype. Comparative analysis of genomic and proteomic data showed that among the insecticidal protein coding genes annotated from the AB1 genome (cry1Aa, cry1Ca, cry1Da, cry1Ia, cry2Ab and cry9), Cry1Ca and Cry1Da toxins represented most of the toxin fraction in parasporal crystals from AB1. Overall findings warrant further development of B. thuringiensis subsp. aizawai AB1 strain as a pesticide to control P. xylostella.

UJI EFIKASI INSEKTISIDA BAHAN AKTIF PERMETRIN 300 g/l TERHADAP POPULASI HAMA ULAT DAUN (Plutella xylostella L) PADA TANAMAN KUBIS (Brassica oleracea)

Cabbage plants (Brassica oleracea) are one of the vegetables that are widely cultivated by farmers in Indonesia, both in the highlands and lowlands. Cabbage plants are usually cultivated at the beginning of the dry season. Cabbage has high production potential and its marketing is relatively easy. So that it is right if the cabbage is prioritized as one of the leaf vegetable plants that needs to be further developed. Cabbage production in the last six years shows a trend of fluctuations every year. Production in 2012 increased by 0.14% to 7,550,021 tons from 7,539,533 tons, then increased by 1.95% to 7,469,013 tons in 2013, and decreased 3.06% to 7,461,697 tons in 2014, then in 2015 it decreased 2.62% to 7,265,840 tons, then in 2016 the production increased to 7,274,126 tons and subsequently in 2017 it increased 2.64%. Fluctuations in cabbage production are inseparable from the effect of an increase or decrease in the area of harvest and the attack of plant pests. The aim of this study was to determine the most effective concentration of the active ingredient of Permethrin 300 g/l to control Plutella xylostella L caterpillar pest in cabbage plants. This research was conducted in Sudimoro Village, Teras Subdistrict, Boyolali Regency at an altitude of 196 m above sea level with alluvial brown soil types, with soil solum thickness > 90 cm. Based on the Oldeman classification, Sudimoro Village is a D3 zone, with a wet month length of 3-4 months and a dry month length of 3-6 months. The method used in the study was a non factorial Complete Group Randomized Design (RAKL) with 5 (five) different concentrations of insecticide treatments. The concentration treatments used were 1 cc/ liters (C1), 0.75 cc/ liters (C2), 0.5 cc/ liters (C3), 0.25 cc/ liters (C4), and control (C5). The results showed that the treatment of the active ingredient concentration of insecticide Permethrin 300 g/l had a very significant effect on the parameters of the Plutella xylostella L population, the weight of the wet stover, the weight of the crop, and the diameter of the crop. However, it does not significantly affect the parameters of plant height and dry stover weight.The effectiveness of the active ingredient insecticide Permethrin 300 g/l in the parameters of the population of Plutella xylostella L is best in the treatment concentration of 0.75 cc/ liters (C2), with a 100% efficacy rate.

Management of insect pests of cabbage with intercropping and their planting pattern

Field experiment was conducted on the incidence of insect pests and natural enemies on cabbage, Brassica oleracea var. capitata. Seven treatments with combinations comprising of three intercrops (fenugreek, lucerne and turnip) with two (linear and square) patterns of planting were evaluated in 2016–17 and 2017–18. Square planting of cabbage with lucerne was observed to be the most effective planting pattern with the least population of Plutella xylostella (0.71 and 0.33/plant), Pieris brassicae (21.98 and 34.95 larvae/plant), aphids (228.25 and 186.13 aphids/plant) along with maximum occurrence of syrphids (1.94 and 1.93 maggots/plant). Also, maximum population of coccinellids of (2.65 and 3.21 grubs+ adults/plant), along with parasitization of P. xylostella (31.39 and 36.12%) and P. brassicae (32.18 and 36.20%) were observed when square planting of cabbage with turnip was followed.

Seasonal incidence of Brevicoryne brassicae and Plutella xylostella on Brassica oleracea in Jind District, Haryana

The maximum population of Brevicoryne brassicae was recorded 352 aphids/plant in 9th SW of year 2017 when the temperature range were 10.2–25.1°C and RH 37–72%. The maximum population of Plutella xylostella in the year 20162017 was recorded 11.40/plant in 6th SW when the temperature range and RH were 10.2–23.1 and 50–89%, respectively. The population of aphid had positive influence of maximum, minimum temperatures and wind fall while RHmorng and RHevng showed negative influence on them. Rainfall did not show any influence on aphid population. Similarly the population of P. xylostella had positive correlation with maximum, minimum temperatures and RH while rainfall and wind speed had positive non-significant correlation.

Functional validation of target-site resistance mutations against sodium channel blocker insecticides (SCBIs) via molecular modeling and genome engineering in Drosophila

Sodium channel blocker insecticides (SCBIs) like indoxacarb and metaflumizone offer an alternative insecticide resistance management (IRM) strategy against several pests that are resistant to other compounds. However, resistance to SCBIs has been reported in several pests, in most cases implicating metabolic resistance mechanisms, although in certain indoxacarb resistant populations of Plutella xylostella and Tuta absoluta, two mutations in the domain IV S6 segment of the voltage-gated sodium channel, F1845Y and V1848I have been identified, and have been postulated through in vitro electrophysiological studies to contribute to target-site resistance.In order to functionally validate in vivo each mutation in the absence of confounding resistance mechanisms, we have employed a CRISPR/Cas9 strategy to generate strains of Drosophila melanogaster bearing homozygous F1845Y or V1848I mutations in the para (voltage-gated sodium channel) gene. We performed toxicity bioassays of these strains compared to wild-type controls of the same genetic background. Our results indicate both mutations confer moderate resistance to indoxacarb (RR: 6–10.2), and V1848I to metaflumizone (RR: 8.4). However, F1845Y confers very strong resistance to metaflumizone (RR: >3400). Our molecular modeling studies suggest a steric hindrance mechanism may account for the resistance of both V1848I and F1845Y mutations, whereby introducing larger side chains may inhibit metaflumizone binding.

Susceptibility of Field Populations of Plutella xylostella and Spodoptera exigua to Four Diamide Insecticides

The present study evaluated the susceptibility of field populations of Plutella xylostella and Spodoptera exigua larvae to four diamide insecticides—chlorantraniliprole, cyantraniliprole, cyclaniliprole, and flubendiamide. All the four diamide insecticides induced 100% mortality in the populations from Seongju (SJ) and Geochang (GC) when treated at a concentration recommended for P. xylostella. However, a very low insecticidal activity was observed in the population from Pyeongchang (PC) with 42.3% 3 d after treatment with chlorantraniliprole. Further, the populations of S. exigua from Cheongju (CJ), Jindo (JD), and Yeonggwang (YG) were not completely controlled by the 4 diamide insecticides. A comparison of susceptibility of S. exigua larvae to chlorantraniliprole between 2014 and 2017 showed that chlorantraniliprole induced 100% mortality in all populations in 2014, whereas a very low insecticidal activity was observed among the populations in 2017. This study can serve as a basis to control pests effectively using diamide insecticides.

Plant Growth Promoting Rhizobacteria (PGPR) and Plutella xylostella (L.) (Lepidoptera: Plutellidae) interaction as a resistance inductor factor in Brassica oleracea var. capitata

Resistance of Plutella xylostella populations to chemical insecticides has made its management difficult, and the utilization of resistant cabbage cultivars has been shown to be a useful alternative. The objective of this study was to demonstrate the induction of cabbage plant resistance to P. xylostella using PGPR and injuries caused by the pest larvae as elicitors. Therefore, we evaluated the insects’ responses utilizing a specific bioassay. Furthermore, this assay was used for selecting a PGPR strain that affects the insect’s biology, and to examine molecular and biochemical responses of the plants influenced by the plant-microbe-insect interaction. Among the strains used in this study, Kluyvera ascorbata showed the most relevant results by influencing biological characteristics of the insect. Thus, the following tests demonstrated that the cited strain possesses a high influence on plant metabolism when it undergoes different types of stress such as injuries caused by the pest. These findings were determined from the different responses obtained by the chemical analyses of the tested plants and from the differentiation in the genetic sequences obtained from plants inoculated with or without PGPR that were injured by the pest. The PGPR K. ascorbata alters the metabolism of cabbage plants, which directs a specific plant defense against P. xylostella.