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The Fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith), is a highly destructive lepidopteran pest known for its extensive feeding on maize (Zea mays L.) and other crops, resulting in a substantial reduction in crop yields. Understanding the metabolic response of maize to FAW infestation is essential for effective pest management and crop protection. Metabolomics, a powerful analytical tool, provides insights into the dynamic changes in maize's metabolic profile in response to FAW infestation. This review synthesizes recent advancements in metabolomics research focused on elucidating maize's metabolic responses to FAW and other lepidopteran pests. It discusses the methodologies used in metabolomics studies and highlights significant findings related to the identification of specific metabolites involved in FAW defense mechanisms. Additionally, it explores the roles of various metabolites, including phytohormones, secondary metabolites, and signaling molecules, in mediating plant–FAW interactions. The review also examines potential applications of metabolomics data in developing innovative strategies for integrated pest management and breeding maize cultivars resistant to FAW by identifying key metabolites and associated metabolic pathways involved in plant–FAW interactions. To ensure global food security and maximize the potential of using metabolomics in enhancing maize resistance to FAW infestation, further research integrating metabolomics with other omics techniques and field studies is necessary. [ABSTRACT FROM AUTHOR]

Effect of sowing dates, climatic variables on major insect pests population, and host plant resistance with special reference to pod borer Helicoverpa armigera (Hubner) in pigeon pea (Cajanus cajan (L.) ecosystem was studied on two cultivars namely, ICPL 87 and ICPL 88039. The insect pest population on two cultivars differed significantly across sowing dates. ICPL 87 was most vulnerable to insect pests as it suffered more damage by the pod borer H. armigera, pod sucking bugs (Clavigralla tomentosicollis Stal.) than ICPL 88039. The maximum leaf/pod feeding insect population was recorded on first sowing and then gradually decline for the rest of the plantings. Maximum H. armigera egg population exhibited 21.10 on ICPL 87 in first sowing and at least 1.23 on ICPL 88039 in sixth sowing. Web forming insect pests Maruca virata (3.95) and leaf webber (4.66) weremaximum recorded on ICPL 88039 in second and first planting respectively. The leaf feeding beetle was recorded highest 6.29(ICPL 87) in the third planting. Amid two cultivars maximum insect-pests population was recorded on ICPL 87 when compared to ICPL 88039 except web forming insect Maruca and leaf webber due to its indeterminate genotypic character of ICPL 88039. Between the two genotypes, the sucking pests more preferred to ICPL 87 when compared ICPL 88039. Maximum jassids were recorded 12.76 and 8.38 (ICPL 87) in fourth sowing and third sowing respectively. It was observed that highest spider population recorded 2.23(ICPL 88039) in first and second sowing. Ladybird beetle Coccinella transvasalis population recorded a maximum 8.52 (ICPL 87). The leaf webber (r= 0.449**) and pod bug (r= 0.421**) showed a highly significant positive correlation with maximum temperature and H. armigera larvae population exhibited highly significant positive correlation with minimum temperature (r= 0.491**) and morning relative humidity (r= 0.528**). Solar radiation also exhibited and showed a significant positive correlation with leaf webber (r= 533**). [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Slovenica is the property of Biotechnical Faculty of the University of Ljubljana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Helicoverpa armigera (Hübner) (Noctuidae: Lepidopetra) is a polyphagous pest of major crops grown in India. To prevent the damage caused by H. armigera farmers rely heavily on insecticides of diverse groups on a regular basis which is not a benign practice, environmentally and economically. To provide more efficient and accurate information on timely application of insecticides, this research was aimed to develop a forecast model to predict population dynamics of pod borer using Autoregressive Integrated Moving Average (ARIMA) and Artificial Neural Networks (ANN). The data used in this study were collected from the randomly installed sex pheromone traps at International Crops Research Institute for the Semi-arid Tropics (ICRISAT), Patancheru, Hyderabad. Several ARIMA (p, d, q) (P, D, Q) and ANN models were developed using the historical trap catch data. ARIMA model (1,0,1), (1,0,2) with minimal BIC, RMSE, MAPE, MAE, and MASE values and higher R2 value (0.53) was selected as the best ARIMA fit model, and neural network (7-30-1) was found to be the best fit to predict the catches of male moths of pod borer from September 2021 to August 2023. A comparative analysis performed between the ARIMA and ANN, shows that the ANN based on feed forward neural networks is best suited for effective pest prediction. With the developed ARIMA model, it would be easier to predict H. armigera adult population dynamics round the year and timely intervention of control measures can be followed by appropriate decision-making schedule for insecticide application. [ABSTRACT FROM AUTHOR]

Simple Summary: Pigeonpea is an important legume crop that is severely affected by various insect pests, especially pod borer. Because there are low resistance levels to pod borers in the cultivated pigeonpea gene pool, it is necessary to introduce resistance-related traits from its wild relatives. In this study, we conducted a series of crosses to introduce traits related to pod borer resistance from two wild relatives of pigeonpea into two popular cultivated varieties. We generated populations from four different crosses and screened these populations for traits related to pod borer resistance: i.e., low levels of insect damage, high concentrations of insect-deterring compounds in the seeds, and the presence of trichomes on the leaves. The most promising lines were tested across seasons and locations. Ultimately, we identified 21 lines with excellent traits related to pod borer resistance. These lines will be useful for breeding new insect-resistant pigeonpea cultivars. The availability of such cultivars will reduce the use of pesticides to control pests on pigeonpea crop. Pod borer (Helicoverpa armigera) causes the highest yield losses in pigeonpea, followed by pod fly (Melanagromyza obtusa). High levels of resistance to pod borer are not available in the cultivated genepool. Several accessions of wild Cajanus species with strong resistance, and different resistance mechanisms (antixenosis and antibiosis) to pod borer have been identified. These accessions can be utilized to improve the pod borer resistance of cultivated pigeonpea. Using pod borer resistant Cajanus scarabaeoides and Cajanus acutifolius as pollen donors and popular pigeonpea varieties as recipients, pre-breeding populations were developed following simple- and complex-cross approaches. Preliminary evaluation of four backcross populations consisting of >2300 introgression lines (ILs) under un-sprayed field conditions resulted in identifying 156 ILs with low visual damage rating scores (5.0–6.0) and low pod borer damage (<50%). Precise re-screening of these ILs over different locations and years resulted in the identification of 21 ILs having improved resistance to pod borer. Because these ILs were derived from wild Cajanus species, they may contain different alleles for different resistance components to pod borer. Hence, these ILs are ready-to-use novel and diverse sources of pod borer resistance that can be utilized for improving the pod borer resistance of cultivated pigeonpea. [ABSTRACT FROM AUTHOR]

Host plant resistance is an important component for minimizing the losses due to the pod borer, Helicoverpa armigera and other pod borer complex. Among pod borer, which is the most devastating pest of pigeonpea. An understanding of different morphological and biochemical components of resistance is essential for developing strategies to breed for resistance to insect pests. morphological and biochemical components associated with expression of resistance to pod borer complex in Pigeonpea hybrids and cultivars to identify accessions with a diverse combination of characteristics associated with resistance to this pest. Among the genotypes ICPH 3461, ICPH 3762, BSMR 853, ICPL 332 WR, ICPH 2740, ENT 11 showed least preference for pod borer complex as compared to susceptible check ICPL 87. In context to morphological factors pod wall thickness, trichome density of type C and D on calyx and pod with correlation coefficient (r) (-0.508*), ( -0.717**, -0.748**), (-0.810**, -0.749**) exhibited a strong negative association with percent pod damage by pod borer complex. Among the biochemical factors protein, sugar content in pigeonpea seeds exhibited significant positive correlation with correlation coffecient (r) being (0.710**, 0.843**), respectively with percent pod damage by pod borer complex. Whereas, total phenols, tannins, total flavonoids present in seeds showed significant negative correlation with correlation coffecient (r) being (-0.729**, - 0.650**, -0.783**), respectively with percent pod damage by pod borer complex. Thus genotypes with maximum pod wall thickness, high non glandular trichome density and high phenol, tannins, flavonoids content in pigeonpea genotypes showed tolerance to pod borer complex. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Slovenica is the property of Biotechnical Faculty of the University of Ljubljana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Efforts are being made to develop chickpea varieties with resistance to the pod borer, Helicoverpa armigera for reducing pesticide use and minimizing the extent of losses due to this pest. However, only low to moderate levels of resistance have been observed in the cultivated chickpea to this polyphagous pest. Hence, it is important to explore wild relatives as resistance sources to develop insect-resistant cultivars. Therefore, we studied different biochemical components that confer resistance to H. armigera in a diverse array of wild relatives of chickpea. Accessions belonging to wild relatives of chickpea exhibited high levels of resistance to H. armigera as compared to cultivated chickpea genotypes in terms of lower larval survival, pupation and adult emergence, decreased larval and pupal weights, prolonged larval and pupal developmental periods and reduced fecundity of the H. armigera when reared on artificial diet impregnated with lyophilized leaf powders. Amounts of proteins and phenols in different accessions of chickpea wild relatives were significantly and negatively correlated with larval weight, pupation and adult emergence. Phenols showed a negative correlation with pupal weight and fecundity, but positive correlation with pupal period. Total soluble sugars showed a negative correlation with larval period, but positive correlation with pupation and pupal weight, while tannins showed a positive correlation with larval weight, pupation and adult emergence. The flavonoid compounds such as chlorogenic acid, ferulic acid, naringin, 3,4-dihydroxy flavones, quercetin, naringenin, genistein, biochanin-A and formononetin that were identified through HPLC fingerprints, exhibited negative effects on survival and development of H. armigera reared on artificial diet impregnated with lyophilized leaf powders. The wild relatives with diverse mechanisms of resistance conferred by different biochemical components can be used as sources of resistance in chickpea breeding programs to develop cultivars with durable resistance to H. armigera for sustainable crop production. [ABSTRACT FROM AUTHOR]

Insights of antibiosis resistance in various chickpea cultivars against pod borer Helicoverpa armigera (Hubner) under laboratory condtions. The present study was carried out in order to investigate the level of resistance against H. armigera on different cultivars by adopting detach leaf and pod assay. In leaf detach assay, pooled mean of 2012 and 2013, significantly lower and maximum weight gain and percent gain recorded was 101.9 mg (88.5%); 382.3mg (317.4%), respectively for ICCV 097105 and ICCV 07306. During podding stage, lowest pod damage (%) was recorded 55 % (ICCV 92944) and highest pod damage recorded by ICC 3137, LL 550 and ICCV07306 (95 %).Highest pupal weight of one day old pupae was recorded on LL 550 (405.2 mg) and lower pupal weight in ICCV 097105 (202.4 mg). The present result gave clue for future in depth studies on weeds for developing either specific pheromone compound or repellant compound for the ecofriendly management of H. armigera. [ABSTRACT FROM AUTHOR]

The investigation was carried out to evaluate bioefficacy of biopesticides such as Jatropha oil, NSKE and NPV in various combinations along with control under chickpea-coriander intercropping ecosystem for three seasons against Helicoverpa armigera. The results revealed that the most effective treatment was T4 (chickpea; Jatropha treated) + coriander (NPV treated) followed by T9 (chickpea; Jatropha treated alone). The pooled mean of lowest damage for 3 years (2011, 2012, and 2013) was in chickpea (Jatropha treated) + coriander (NPV treated) treatments followed by chickpea (Jatropha treated) treatment alone. The mean grain yield of 1292 kg/ha was recorded for T4 treatment in chickpea (Jatropha at 5 mL/L) + coriander (NPV at 0.5 mL/L). The maximum coriander yield of 1008 kg/ha was obtained in T2 treatment, i.e., chickpea (NSKE treated) + coriander (untreated). The present results suggest that Jatropha curcas seed oil either alone or in combination with other biopesticides could be used as botanical insecticide against chickpea pests under any integrated pest management strategy for insect pest control. [ABSTRACT FROM AUTHOR]

A laboratory experiment was conducted to evaluate the efficacy of different biopesticides against the second instar larva of Helicoverpa armigera at International Crops Research Institute for the Semi-Arid Tropics during 2016-2017. Varied doses of biopesticides were used during experiment against second instar larvae of H. armigera and recorded the per cent morality. Among the selected biopesticides neem seed powder, HaNPV and Spinosad showed superior and recorded maximum per cent morality at 24 hr and 48 hr day after release. The metarhizium anisopliae, Streptomyces sp. and consortia were at par with each other. [ABSTRACT FROM AUTHOR]

• Improved parental lines were evaluated for morphological and physio-chemical traits. • Morphological and Biochemical traits impact expression of resistance to shoot fly. • HPLC and GC–MS fingerprints revealed diverse mechanisms of resistance to shoot fly. • Morpho-biochemical traits can be used as markers for selecting resistant germplasm. Sorghum shoot fly, Atherigona soccata, causes substantial economic losses in sorghum globally. Cultural practices and host plant resistance are effective measures for mitigating the losses caused by sorghum shoot fly. Therefore, we evaluated 32 sorghum genotypes consisting of a set of 10 restorer lines, 10 CMS (cytoplasmic male-sterile) lines and their respective maintainers exhibiting resistance/susceptibility to shoot fly along with resistant and susceptible checks under field conditions. The traits such as leaf glossiness, leaf sheath pigmentation, percentage plants with shoot fly deadhearts and number of shoot fly eggs per plant were used as morphological markers for selecting genotypes with resistance to shoot fly during the rainy and post rainy seasons of 2016 and 2017. The test material was also subjected to biochemical analysis (total soluble sugars, protein and tannin contents), while the leaf surface chemicals were analysed by GC–MS to identify the compounds associated with resistance/susceptibility to shoot fly. The genotypes differed significantly for all the traits, except percentage plants with shoot fly deadhearts during the 2016 rainy season. The genotypes ICSB 458, ICSA/B 467, ICSA/B 487, ICSA/B 14037, IS 18551 and ICSV 93046 exhibited moderate to high levels of resistance to shoot fly based on number of plants with shoot fly deadhearts, plants with shoot fly eggs and total number of shoot fly eggs. The shoot fly resistant genotypes ICSB 84, ICSA/B 467, ICSB 487, ICSB 14024, and IS 18551 had low shoot fly deadheart incidence, higher amounts of condensed tannins, soluble sugars, phenols and lower protein content as compared to the susceptible genotypes. Thirteen unique compounds were identified from leaf surface extracts by GC–MS which were associated with shoot fly resistance/susceptibility. While HPLC analysis revealed that Protocatechuic and coumaric acids were present in most of the sorghum genotypes, but their amounts were significantly greater in resistant as compared to the susceptible ones. The findings of the study highlight the importance of various morphological and biochemical traits conferring resistance to sorghum shoot fly, and these traits can be used as markers to identify shoot fly resistant genotypes for use in breeding programs. [ABSTRACT FROM AUTHOR]

Genetic enhancement for resistance against the pod borer, Helicoverpa armigera is crucial for enhancing production and productivity of chickpea. Here we provide some novel insights into the genetic architecture of natural variation in H. armigera resistance in chickpea, an important legume, which plays a major role in food and nutritional security. An interspecific recombinant inbred line (RIL) population developed from a cross between H. armigera susceptible accession ICC 4958 (Cicer arietinum) and resistant accession PI 489777 (Cicer reticulatum) was evaluated for H. armigera resistance component traits using detached leaf assay and under field conditions. A high-throughput AxiomCicerSNP array was utilized to construct a dense linkage map comprising of 3,873 loci and spanning a distance of 949.27 cM. Comprehensive analyses of extensive genotyping and phenotyping data identified nine main-effect QTLs and 955 epistatic QTLs explaining up to 42.49% and 38.05% phenotypic variance, respectively, for H. armigera resistance component traits. The main-effect QTLs identified in this RIL population were linked with previously described genes, known to modulate resistance against lepidopteran insects in crop plants. One QTL cluster harbouring main-effect QTLs for three H. armigera resistance component traits and explaining up to 42.49% of the phenotypic variance, was identified on CaLG03. This genomic region, after validation, may be useful to improve H. armigera resistance component traits in elite chickpea cultivars., (© 2020 The Authors. The Plant Genome published by Wiley Periodicals LLC on behalf of Crop Science Society of America.)