Plant Responses to Insect Herbivores

A topical collection in Insects (ISSN 2075-4450). This collection belongs to the section "Insect Behavior and Pathology".

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Editors


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Collection Editor
Department of Botany, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
Interests: plant ecophysiology; photosynthesis; biotic stress; abiotic stress; antioxidative mechanisms; photoprotective mechanisms; reactive oxygen species
Special Issues, Collections and Topics in MDPI journals

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Collection Editor
Institute of Plant Breeding and Genomic Resources, Hellenic Agricultural Organization - "DEMETER", 57001 Thermi, Greece
Interests: chemical ecology; insect-plant-microbes interactions; integrated pest management; invasive species; management of insect vectors; insects as food

Topical Collection Information

Dear Colleagues,

Insect herbivores are the most abundant and diverse attackers of plants, thereby inducing defensive traits that influence consumers at higher trophic levels. Heavy invasions of phloem-feeding herbivores cause prolonged deficiencies of photosynthates and lead to a severe reduction in plant growth. Herbivore insects alter photosynthetic activity and/or photosynthetic gene expression levels in the affected plants. The effects on photosynthesis were determined with the use of chlorophyll fluorescence and thermal imaging system techniques. Foliage damage by insects down-regulates the expression of photosynthesis-related genes, as an adaptive response that allows plants to invest resources in immediate insect defense needs, debilitating near term losses in photosynthetic capacity.
Plants have evolved complex defence mechanisms to withstand and counter herbivore attack with a variety of induced responses. Upon attack by insect herbivores, plants emit a mixture of volatile organic compounds that can act as both attractants and repellents to further colonization by the same or other insect species. These herbivore-induced plant-volatiles can provide specific information on the status of the plant to various community members both below and aboveground, including predators, herbivores, pollinators, or neighboring plants. Moreover, plants are known to synthesize a range of secondary metabolites in response to insect herbivores that either exist in biologically active forms or are stored as inactive precursors and converted by host enzymes to active forms in response to attack or tissue damage. With the application of new modern methods, a better understanding of the interactions between plants and insects can be revealed that can transform crop production through increased disease resistance and crop yield.
We would like to take this opportunity to invite contributions from experts. We encourage original research submissions, as well as review/mini review articles, concerning basic aspects and future directions in the field.

Prof. Michael Moustakas
Dr. Stefanos Andreadis
Collection Editors

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Keywords

  • insect herbivores
  • photosynthesis
  • defense response
  • plant-insect interactions
  • plant volatiles
  • secondary metabolites

Published Papers (14 papers)

2024

Jump to: 2023, 2022, 2021, 2020

12 pages, 1193 KiB  
Article
Implications of Temperature and Prey Density on Predatory Mite Amblyseius swirskii (Acari: Phytoseiidae) Functional Responses
by Mohammed M. E. Elmoghazy, Dalia Mahmoud Abdelmonem Elsherbini, Abadi M. Mashlawi, Ateya Megahed Ibrahim, Ahmed A. El-Mansi and Mohamed El-Sherbiny
Insects 2024, 15(6), 444; https://doi.org/10.3390/insects15060444 - 12 Jun 2024
Viewed by 1198
Abstract
Amblyseius swirskii are predaceous mites that feed on phytophagous mites, pollens, and plant exudates and are known as one of the most potent biological pest management agents. Tetranychus urticae is a global mite that is difficult to manage because of its high population [...] Read more.
Amblyseius swirskii are predaceous mites that feed on phytophagous mites, pollens, and plant exudates and are known as one of the most potent biological pest management agents. Tetranychus urticae is a global mite that is difficult to manage because of its high population growth rates, necessitating alternative management measures like biological control. Regarding the functional response, the effects of temperature and prey density are some of the essential behaviors of natural enemies. This study investigates the effect of varying temperatures and prey densities on A. swirskii, a biological control agent for T. urticae. The present results demonstrated the change in the functional response estimates when A. swirskii was reared at various temperatures and different prey densities. The results of the estimates regarding the searching efficiency (a′) showed the highest value (a′ = 0.919) at 26 °C and the lowest value (a′ = 0.751) at 14 °C. The handling time per prey item (Th) for the predatory mites changed with the temperature and prey density, showing the shortest handling time at 26 °C (Th = 0.005) and the highest value at 14 °C (Th = 0.015). The functional response curves matched the type II functional response model, demonstrating the inverse dependence of temperatures and prey density with a positive quadratic coefficient. The predation curves for A. swirskii showed a significant difference between the mean numbers of T. urticae consumed at various prey densities and temperatures, illustrating a relationship between A. swirskii and T. urticae. Therefore, the results of this research may be utilized to forecast the behavior of A. swirskii and its usefulness in controlling T. urticae populations. Full article
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35 pages, 1665 KiB  
Review
Virulence Adaptation by Rice Planthoppers and Leafhoppers to Resistance Genes and Loci: A Review
by Finbarr G. Horgan
Insects 2024, 15(9), 652; https://doi.org/10.3390/insects15090652 - 29 Aug 2024
Viewed by 767
Abstract
In recent decades, research on developing and deploying resistant rice has accelerated due to the availability of modern molecular tools and, in particular, advances in marker-assisted selection. However, progress in understanding virulence adaptation has been relatively slow. This review tracks patterns in virulence [...] Read more.
In recent decades, research on developing and deploying resistant rice has accelerated due to the availability of modern molecular tools and, in particular, advances in marker-assisted selection. However, progress in understanding virulence adaptation has been relatively slow. This review tracks patterns in virulence adaptation to resistance genes (particularly Bph1, bph2, Bph3, and bph4) and examines the nature of virulence based on selection experiments, responses by virulent populations to differential rice varieties (i.e., varieties with different resistance genes), and breeding experiments that interpret the genetic mechanisms underlying adaptation. The review proposes that varietal resistance is best regarded as a combination of minor and major resistance traits against which planthoppers develop partial or complete virulence through heritable improvements that are reversable or through evolutionary adaptation, respectively. Agronomic practices, deployment patterns, and herbivore population pressures determine the rates of adaptation, and there is growing evidence that pesticide detoxification mechanisms can accelerate virulence adaptation. Research to delay adaptation has mainly focused on gene pyramiding (i.e., including ≥ two major genes in a variety) and multilines (i.e., including ≥ two resistant varieties in a field or landscape); however, these strategies have not been adequately tested and, if not managed properly, could inadvertently accelerate adaptation compared to sequential deployment. Several research gaps remain and considerable improvements in research methods are required to better understand and manage virulence adaptation. Full article
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2023

Jump to: 2024, 2022, 2021, 2020

19 pages, 7672 KiB  
Article
Biochemical Defense Responses in Red Rice Genotypes Possessing Differential Resistance to Brown Planthopper, Nilaparvata lugens (Stål)
by Prajna Pati, Mayabini Jena, Swarnali Bhattacharya, Santhosh Kumar Behera, Subhajit Pal, Raghu Shivappa and Tapamay Dhar
Insects 2023, 14(7), 632; https://doi.org/10.3390/insects14070632 - 13 Jul 2023
Cited by 5 | Viewed by 1683
Abstract
The brown planthopper [Nilaparvata lugens (Stål.)] is one of the most destructive insect pests in all the rice-growing regions of the world. The pest is complicated to manage through the blanket application of chemical pesticides. The development of stable, durable N. lugens [...] Read more.
The brown planthopper [Nilaparvata lugens (Stål.)] is one of the most destructive insect pests in all the rice-growing regions of the world. The pest is complicated to manage through the blanket application of chemical pesticides. The development of stable, durable N. lugens-resistant rice varieties is the most economical and efficient strategy to manage the pest. Landraces of red rice genotypes possess numerous nutritional and stress-resistant properties, though an exclusive study on the same is yet to be carried out. In the present study, we evaluated 28 red rice genotypes, along with two resistance checks and one susceptibility check, for their resistance to N. lugens. These promising lines revealed differential responses in the defense mechanism against the pest. The resistant accessions showed a greater accumulation of phenols, peroxidase, polyphenol oxidase, catalase, and superoxide dismutase under N. lugens-stressed conditions. However, the concentration of soluble proteins was substantially decreased in all the test genotypes. The concentration of crude silica was at maximum in highly resistant genotypes. Six red rice genotypes, namely Mata Meher, Manipuri Black, Hermonona, Sonahanan, Bavdi, and Bacharya Khuta fall under the highly resistant category, and can be utilized as valuable sources of resistance in breeding programs. Full article
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2022

Jump to: 2024, 2023, 2021, 2020

14 pages, 1423 KiB  
Article
Chinese Cabbage Changes Its Release of Volatiles to Defend against Spodoptera litura
by Yuan-Wen Du, Xiao-Bin Shi, Lin-Chao Zhao, Ge-Ge Yuan, Wei-Wei Zhao, Guo-Hua Huang and Gong Chen
Insects 2022, 13(1), 73; https://doi.org/10.3390/insects13010073 - 10 Jan 2022
Cited by 10 | Viewed by 2792
Abstract
Plants respond to herbivorous insect attacks by releasing volatiles that directly harm the herbivore or that indirectly harm the herbivore by attracting its natural enemies. Although the larvae of Spodoptera litura (the tobacco cutworm) are known to induce the release of host plant [...] Read more.
Plants respond to herbivorous insect attacks by releasing volatiles that directly harm the herbivore or that indirectly harm the herbivore by attracting its natural enemies. Although the larvae of Spodoptera litura (the tobacco cutworm) are known to induce the release of host plant volatiles, the effects of such volatiles on host location by S. litura and by the parasitoid Microplitis similis, a natural enemy of S. litura larvae, are poorly understood. Here, we found that both the regurgitate of S. litura larvae and S. litura-infested cabbage leaves attracted M. similis. S. litura had a reduced preference for cabbage plants that had been infested with S. litura for 24 or 48 h. M. similis selection of plants was positively correlated with the release of limonene; linalool and hexadecane, and was negatively correlated with the release of (E)-2-hexenal and 1-Butene, 4-isothiocyanato. S. litura selection of plants was positively correlated with the release of (E)-2-hexenal, 1-Butene, 4-isothiocyanato, and decanal, and was negatively correlated with the release of limonene, nonanal, hexadecane, heptadecane, and octadecane. Our results indicate that host plant volatiles can regulate the behavior of S. litura and M. similis. Full article
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15 pages, 6265 KiB  
Article
Reactive Oxygen Species Initiate Defence Responses of Potato Photosystem II to Sap-Sucking Insect Feeding
by Ilektra Sperdouli, Stefanos S. Andreadis, Ioannis-Dimosthenis S. Adamakis, Julietta Moustaka, Eleni I. Koutsogeorgiou and Michael Moustakas
Insects 2022, 13(5), 409; https://doi.org/10.3390/insects13050409 - 24 Apr 2022
Cited by 19 | Viewed by 3503
Abstract
Potato, Solanum tuberosum L., one of the most commonly cultivated horticultural crops throughout the world, is susceptible to a variety of herbivory insects. In the present study, we evaluated the consequence of feeding by the sap-sucking insect Halyomorpha halys on potato leaf photosynthetic [...] Read more.
Potato, Solanum tuberosum L., one of the most commonly cultivated horticultural crops throughout the world, is susceptible to a variety of herbivory insects. In the present study, we evaluated the consequence of feeding by the sap-sucking insect Halyomorpha halys on potato leaf photosynthetic efficiency. By using chlorophyll fluorescence imaging methodology, we examined photosystem II (PSII) photochemistry in terms of feeding and at the whole leaf area. The role of reactive oxygen species (ROS) in potato’s defence response mechanism immediately after feeding was also assessed. Even 3 min after feeding, increased ROS generation was observed to diffuse through the leaf central vein, probably to act as a long-distance signalling molecule. The proportion of absorbed energy being used in photochemistry (ΦPSII) at the whole leaf level, after 20 min of feeding, was reduced by 8% compared to before feeding due to the decreased number of open PSII reaction centres (qp). After 90 min of feeding, ΦPSII decreased by 46% at the whole leaf level. Meanwhile, at the feeding zones, which were located mainly in the proximity of the leaf midrib, ΦPSII was lower than 85%, with a concurrent increase in singlet-excited oxygen (1O2) generation, which is considered to be harmful. However, the photoprotective mechanism (ΦNPQ), which was highly induced 90 min after feeding, was efficient to compensate for the decrease in the quantum yield of PSII photochemistry (ΦPSII). Therefore, the quantum yield of non-regulated energy loss in PSII (ΦNO), which represents 1O2 generation, remained unaffected at the whole leaf level. We suggest that the potato PSII response to sap-sucking insect feeding underlies the ROS-dependent signalling that occurs immediately and initiates a photoprotective PSII defence response to reduce herbivory damage. A controlled ROS burst can be considered the primary plant defence response mechanism to herbivores. Full article
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16 pages, 3095 KiB  
Article
The Differential Effects of Tuta absoluta Infestations on the Physiological Processes and Growth of Tomato, Potato, and Eggplant
by Lindiwe Mahlangu, Phumzile Sibisi, Robert S. Nofemela, Titus Ngmenzuma and Khayalethu Ntushelo
Insects 2022, 13(8), 754; https://doi.org/10.3390/insects13080754 - 22 Aug 2022
Cited by 1 | Viewed by 3333
Abstract
Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae) is a destructive insect pest toward crops and belongs to the Solanaceae family. Since it was first recorded in South Africa in 2016, the pest has spread extensively and caused tremendous damage to field [...] Read more.
Tuta absoluta (Meyrick, 1917) (Lepidoptera: Gelechiidae) is a destructive insect pest toward crops and belongs to the Solanaceae family. Since it was first recorded in South Africa in 2016, the pest has spread extensively and caused tremendous damage to field and tunnel-grown tomato crops. This study aimed to investigate how T. absoluta affects the growth and physiology of three Solanaceae plant species: tomato, potato, and eggplant. These three crops were infested with L1 instar larvae, and their growth and physiology were assessed during insect feeding. The damage to the infested tomato host plant was severe, with T. absoluta destroying 100% of the plants. The tomato plants were distorted 15 days after infestation, that is, before the fruit set. For potato, the defoliation was moderate, but the infested plants produced fewer tubers compared to the uninfested host plants. Eggplant had fewer visible signs of feeding, resulting in no significant difference between the infested and uninfested host plants in terms of growth and physiological functions. Infested tomato and potato plants had stagnant growth, fewer and damaged leaves, a reduced chlorophyll content, a reduced photosynthesis rate, a poor transpiration rate, poor water conductance, and poor intercellular carbon dioxide concentrations. This study closes the knowledge gap on the morphological (growth) and physiological responses of different Solanaceae species to T. absoluta infestation, and it also demonstrates the differential risk of T. absoluta infestations in the production of tomato, potato, and eggplant. Full article
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11 pages, 8164 KiB  
Article
Comparative Analysis of Volatiles Emitted from Tomato and Pepper Plants in Response to Infection by Two Whitefly-Transmitted Persistent Viruses
by Saptarshi Ghosh, Shoshana Didi-Cohen, Alon Cna’ani, Svetlana Kontsedalov, Galina Lebedev, Vered Tzin and Murad Ghanim
Insects 2022, 13(9), 840; https://doi.org/10.3390/insects13090840 - 15 Sep 2022
Cited by 4 | Viewed by 3800
Abstract
The whitefly Bemisia tabaci is one of the most important agricultural pests due to its extreme invasiveness, insecticide resistance, and ability to transmit hundreds of plant viruses. Among these, Begomoviruses and recombinant whitefly-borne Poleroviruses are transmitted persistently. Several studies have shown that upon [...] Read more.
The whitefly Bemisia tabaci is one of the most important agricultural pests due to its extreme invasiveness, insecticide resistance, and ability to transmit hundreds of plant viruses. Among these, Begomoviruses and recombinant whitefly-borne Poleroviruses are transmitted persistently. Several studies have shown that upon infection, plant viruses manipulate plant-emitted volatile organic compounds (VOCs), which have important roles in communication with insects. In this study, we profiled and compared the VOCs emitted by tomato and pepper plant leaves after infection with the Tomato yellow leaf curl virus (TYLCV) (Bogomoviruses) and the newly discovered Pepper whitefly-borne vein yellows virus (PeWBVYV) (Poleroviruses), respectively. The results identified shared emitted VOCs but also uncovered unique VOC signatures for each virus and for whitefly infestation (i.e., without virus infection) independently. The results suggest that plants have general defense responses; however, they are also able to respond individually to infection with specific viruses or infestation with an insect pest. The results are important to enhance our understanding of virus- and insect vector-induced alteration in the emission of plant VOCs. These volatiles can eventually be used for the management of virus diseases/insect vectors by either monitoring or disrupting insect–plant interactions. Full article
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22 pages, 6908 KiB  
Article
Fall Armyworm Infestation and Development: Screening Tropical Maize Genotypes for Resistance in Zambia
by Chapwa Kasoma, Hussein Shimelis, Mark D. Laing and Bethelihem Mekonnen
Insects 2022, 13(11), 1020; https://doi.org/10.3390/insects13111020 - 4 Nov 2022
Cited by 5 | Viewed by 4578
Abstract
Knowledge of fall armyworm (FAW) (Spodoptera frugiperda J.E. Smith) rearing, infestation and development and precision screening protocols are preconditions for the successful introgression of resistance genes into farmer-preferred varieties. We aimed to determine FAW developmental stages, screen tropical maize and select resistant [...] Read more.
Knowledge of fall armyworm (FAW) (Spodoptera frugiperda J.E. Smith) rearing, infestation and development and precision screening protocols are preconditions for the successful introgression of resistance genes into farmer-preferred varieties. We aimed to determine FAW developmental stages, screen tropical maize and select resistant lines under controlled conditions in Zambia. Field-collected FAW samples constituting 30 egg masses and 60 larvae were reared using maize leaf- and stalk-based and soy- and wheat flour-based diets at 27 ± 1 °C, 60 ± 5% relative humidity and 12 h day length. The resulting neonates were separated into sets A and B. The life cycles of set A and field-collected larvae were monitored to document the FAW developmental features. Set B neonates were used to infest the seedlings of 63 diverse tropical maize genotypes. Egg, larva, pupa and adult stages had mean durations of 2, 24, 20 and 12 days, respectively. Test maize genotypes revealed significant differences (p < 0.05) based on FAW reaction types, with lines TL13159, TL02562, TL142151, VL050120 and CML548-B exhibiting resistance reactions, while CML545-B, CZL1310c, CZL16095, EBL169550, ZM4236 and Pool 16 displayed moderate resistance. These genotypes are candidate sources of FAW resistance for further breeding. This study will facilitate controlled FAW rearing for host screening in the integration of FAW resistance into market-preferred maize lines. Full article
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2021

Jump to: 2024, 2023, 2022, 2020

15 pages, 4743 KiB  
Article
Induction of a Compensatory Photosynthetic Response Mechanism in Tomato Leaves upon Short Time Feeding by the Chewing Insect Spodoptera exigua
by Julietta Moustaka, Nicolai Vitt Meyling and Thure Pavlo Hauser
Insects 2021, 12(6), 562; https://doi.org/10.3390/insects12060562 - 18 Jun 2021
Cited by 35 | Viewed by 3543
Abstract
In addition to direct tissue consumption, herbivory may affect other important plant processes. Here, we evaluated the effects of short-time leaf feeding by Spodoptera exigua larvae on the photosynthetic efficiency of tomato plants, using chlorophyll a fluorescence imaging analysis. After 15 min of [...] Read more.
In addition to direct tissue consumption, herbivory may affect other important plant processes. Here, we evaluated the effects of short-time leaf feeding by Spodoptera exigua larvae on the photosynthetic efficiency of tomato plants, using chlorophyll a fluorescence imaging analysis. After 15 min of feeding, the light used for photochemistry at photosystem II (PSII) (ΦPSII), and the regulated heat loss at PSII (ΦNPQ) decreased locally at the feeding zones, accompanied by increased non-regulated energy losses (ΦNO) that indicated increased singlet oxygen (1O2) formation. In contrast, in zones neighboring the feeding zones and in the rest of the leaf, ΦPSII increased due to a decreased ΦNPQ. This suggests that leaf areas not directly affected by herbivory compensate for the photosynthetic losses by increasing the fraction of open PSII reaction centers (qp) and the efficiency of these centers (Fv’/Fm’), because of decreased non-photochemical quenching (NPQ). This compensatory reaction mechanism may be signaled by singlet oxygen formed at the feeding zone. PSII functionality at the feeding zones began to balance with the rest of the leaf 3 h after feeding, in parallel with decreased compensatory responses. Thus, 3 h after feeding, PSII efficiency at the whole-leaf level was the same as before feeding, indicating that the plant managed to overcome the feeding effects with no or minor photosynthetic costs. Full article
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15 pages, 5547 KiB  
Article
Anatomy and Ultrastructure of Galls Induced by Neuroterus quercusbaccarum (Hymenoptera: Cynipidae) on Oak Leaves (Quercus robur)
by Leszek Stanisław Jankiewicz, Marzenna Guzicka and Agnieszka Marasek-Ciolakowska
Insects 2021, 12(10), 850; https://doi.org/10.3390/insects12100850 - 22 Sep 2021
Cited by 5 | Viewed by 3401
Abstract
The structure and ultrastructure of two developmental stages of the spangle gall induced by Neuroterus quercusbaccarum (Hymenoptera, Cynipidae) were investigated using light microscopy (LM), fluorescence microscopy (FM), and transmission (TEM) and scanning (SEM) electron microscopy. The general design of the gall structure was [...] Read more.
The structure and ultrastructure of two developmental stages of the spangle gall induced by Neuroterus quercusbaccarum (Hymenoptera, Cynipidae) were investigated using light microscopy (LM), fluorescence microscopy (FM), and transmission (TEM) and scanning (SEM) electron microscopy. The general design of the gall structure was typical of Cynipidae, but some structural features distinguished the spangle gall. Previously undescribed, characteristic multicellular epidermal protuberances with large openings were observed in autumn on the surface of galls. These may facilitate the gas exchange between the atmosphere and the inside of the gall, thus assisting larval respiration. The larval chamber is surrounded by both a sclerenchymatous capsule and numerous cells containing calcium oxalate crystals that may both serve as protective barriers. In young galls, the nutritive tissue is a wall-less protoplasmic mass, potentially easily accessible to young larvae with delicate mandibles. Cell walls only develop at a later stage. The nutritive tissue was found to be rich in proteins and lipids, but starch grains were not observed. Cellular topology suggests that spangle galls grow by anticlinal division of marginal epidermal cells and periclinal division of subepidermal cells. Cellular proliferation (hyperplasia) also occurs in the leaf tissue near the connection with the gall peduncle, which eventually lignifies. Full article
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11 pages, 1144 KiB  
Article
Evaluation of Resistance Development in Bemisia tabaci Genn. (Homoptera: Aleyrodidae) in Cotton against Different Insecticides
by Muhammad Zaryab Khalid, Sohail Ahmed, Ibrahim Al-Ashkar, Ayman EL Sabagh, Liyun Liu and Guohua Zhong
Insects 2021, 12(11), 996; https://doi.org/10.3390/insects12110996 - 5 Nov 2021
Cited by 17 | Viewed by 2779
Abstract
Cotton is a major crop of Pakistan, and Bemisia tabaci (Homoptera: Aleyrodidae) is a major pest of cotton. Due to the unwise and indiscriminate use of insecticides, resistance develops more readily in the whitefly. The present study was conducted to evaluate the resistance [...] Read more.
Cotton is a major crop of Pakistan, and Bemisia tabaci (Homoptera: Aleyrodidae) is a major pest of cotton. Due to the unwise and indiscriminate use of insecticides, resistance develops more readily in the whitefly. The present study was conducted to evaluate the resistance development in the whitefly against the different insecticides that are still in use. For this purpose, the whitefly population was selected with five concentrations of each insecticide, for five generations. At G1, compared with the laboratory susceptible population, a very low level of resistance was observed against bifenthrin, cypermethrin, acetamiprid, imidacloprid, thiamethoxam, nitenpyram, chlorfenapyr, and buprofezin with a resistance ratio of 3-fold, 2-fold, 1-fold, 4-fold, 3-fold, 3-fold, 3-fold, and 3-fold, respectively. However, the selection for five generations increased the resistance to a very high level against buprofezin (127-fold), and to a high level against imidacloprid (86-fold) compared with the laboratory susceptible population. While, a moderate level of resistance was observed against cypermethrin (34-fold), thiamethoxam (34-fold), nitenpyram (30-fold), chlorfenapyr (29-fold), and acetamiprid (21-fold). On the other hand, the resistance was low against bifenthrin (18-fold) after selection for five generations. A very low level of resistance against the field population of B. tabaci, at G1, showed that these insecticides are still effective, and thus can be used under the field conditions for the management of B. tabaci. However, the proper rotation of insecticides among different groups can help to reduce the development of resistance against insecticides. Full article
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2020

Jump to: 2024, 2023, 2022, 2021

18 pages, 3545 KiB  
Article
Transcriptomic and Metabolomic Responses of Rice Plants to Cnaphalocrocis medinalis Caterpillar Infestation
by Yuqi Wang, Qingsong Liu, Lixiao Du, Eric M. Hallerman and Yunhe Li
Insects 2020, 11(10), 705; https://doi.org/10.3390/insects11100705 - 15 Oct 2020
Cited by 27 | Viewed by 4140
Abstract
Interactions between plants and insect herbivores are important determinants of plant productivity in cultivated and natural agricultural fields. The rice leaf folder (Cnaphalocrocis medinalis) causes tremendous damage to rice production in Asian countries. However, little information is available about how rice [...] Read more.
Interactions between plants and insect herbivores are important determinants of plant productivity in cultivated and natural agricultural fields. The rice leaf folder (Cnaphalocrocis medinalis) causes tremendous damage to rice production in Asian countries. However, little information is available about how rice plants defend themselves against this destructive pest at molecular and biochemical levels. Here, we observed the transcriptomic and metabolomic differences in rice leaves after 0, 1, 6, 12, and 24 h of being fed by C. medinalis using RNA sequencing and metabolome profiling. Transcriptional analyses showed that gene expression responds rapidly to leaf folder infestation, with the most significant transcriptional changes occurring within 6 h after the initiation of feeding. Metabolite abundance changed more slowly than gene expression. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the rice transcriptional response to infestation involved genes encoding protein kinases, transcription factors, biosynthesis of secondary metabolites, photosynthesis, and phytohormone signaling. Moreover, the jasmonic acid-dependent signaling pathway triggered by leaf folder herbivory played a vital role in rice defense against this pest. Taken together, our results provide comprehensive insights into the defense system of rice to this species and may inform the development of insect-resistant rice varieties. Full article
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12 pages, 3093 KiB  
Article
Diamondback Moth Larvae Trigger Host Plant Volatiles that Lure Its Adult Females for Oviposition
by Mubasher Hussain, Jing Gao, Summyya Bano, Liande Wang, Yongwen Lin, Steve Arthurs, Muhammad Qasim and Runqian Mao
Insects 2020, 11(11), 725; https://doi.org/10.3390/insects11110725 - 23 Oct 2020
Cited by 8 | Viewed by 3033
Abstract
The diamondback moth (DBM) is a destructive pest of crucifer crops. In this study, DBM larvae shown to herbivore induced plant volatiles (HIPVs) that were attractive to adult females exposed in a Y-tube olfactometer. Our results showed that olfactory responses of adult females [...] Read more.
The diamondback moth (DBM) is a destructive pest of crucifer crops. In this study, DBM larvae shown to herbivore induced plant volatiles (HIPVs) that were attractive to adult females exposed in a Y-tube olfactometer. Our results showed that olfactory responses of adult females to HIPVs induced by third instar larvae feeding on Barbarea vulgaris were significantly higher (20.40 ± 1.78; mean moths (%) ± SD) than those induced by first instar larvae (14.80 ± 1.86; mean moths (%) ± SD). Meanwhile, a significant concentration of Sulphur-containing isothiocyanate, 3-methylsulfinylpropyl isothiocyanate, and 4-methylsulfinyl-3-butenyl isothiocyanate were detected in HIPVs released by third instar larvae compared to those released by first instar larvae while feeding on B. vulgaris. When the DBM females were exposed to synthetic chemicals, singly and in blend form, a similar response was observed as to natural HIPVs. Our study demonstrated that the relationship between isothiocyanates acting as plant defense compounds, host plant cues emission and regulation of the DBM adult female behavior due to key volatile triggered by the DBM larvae feeding on B. vulgaris. Full article
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18 pages, 958 KiB  
Article
Data on Herbivore Performance and Plant Herbivore Damage Identify the Same Plant Traits as the Key Drivers of Plant–Herbivore Interaction
by Zuzana Münzbergová and Jiří Skuhrovec
Insects 2020, 11(12), 865; https://doi.org/10.3390/insects11120865 - 4 Dec 2020
Cited by 4 | Viewed by 3037
Abstract
Data on plant herbivore damage as well as on herbivore performance have been previously used to identify key plant traits driving plant–herbivore interactions. The extent to which the two approaches lead to similar conclusions remains to be explored. We determined the effect of [...] Read more.
Data on plant herbivore damage as well as on herbivore performance have been previously used to identify key plant traits driving plant–herbivore interactions. The extent to which the two approaches lead to similar conclusions remains to be explored. We determined the effect of a free-living leaf-chewing generalist caterpillar, Spodoptera littoralis (Lepidoptera: Noctuidae), on leaf damage of 24 closely related plant species from the Carduoideae subfamily and the effect of these plant species on caterpillar growth. We used a wide range of physical defense leaf traits and leaf nutrient contents as the plant traits. Herbivore performance and leaf damage were affected by similar plant traits. Traits related to higher caterpillar mortality (higher leaf dissection, number, length and toughness of spines and lower trichome density) also led to higher leaf damage. This fits with the fact that each caterpillar was feeding on a single plant and, thus, had to consume more biomass of the less suitable plants to obtain the same amount of nutrients. The key plant traits driving plant–herbivore interactions identified based on data on herbivore performance largely corresponded to the traits identified as important based on data on leaf damage. This suggests that both types of data may be used to identify the key plant traits determining plant–herbivore interactions. It is, however, important to carefully distinguish whether the data on leaf damage were obtained in the field or in a controlled feeding experiment, as the patterns expected in the two environments may go in opposite directions. Full article
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