scholarly journals Fitness Costs of Chlorantraniliprole Resistance Related to the SeNPF Overexpression in the Spodoptera exigua (Lepidoptera: Noctuidae)

2021 ◽  
Vol 22 (9) ◽  
pp. 5027
Author(s):  
Changwei Gong ◽  
Xinge Yao ◽  
Qunfang Yang ◽  
Xuegui Wang ◽  
Yuming Zhang ◽  
...  

Spodopteraexigua, a multifeeding insect pest, has developed a high level of resistance to chlorantraniliprole, which is a benzoylurea insecticide that targets the ryanodine receptors (RyRs). Herein, the resistant strain (SE-Sel) and sensitive strain (SE-Sus) were obtained by bidirectional screening for six generations. The potential oviposited eggs and oviposition rate of the SE-Sel strain were dramatically lower than those of the SE-Sus strain; on the contrary, the weights of prepupae and preadult were significantly increased. As a post-mating response, the higher number of non-oviposited eggs in the SE-Sel strain was caused by a lower mating rate. In addition, the expression levels of vitellogenin (SeVg) and its receptor (SeVgR) in the SE-Sel strain were consistently lower than those in the SE-Sus strain. An RyRI4743M mutation, contributing to the resistance to chlorantraniliprole, was located in the S3 transmembrane segments and might have affected the release of calcium ions; it led to the upregulated expression of the neuropeptide SeNPF and its receptor SeNPFR, and the mating and oviposition rate were significantly recovered when the SeNPF was knocked down though RNA interference (RNAi) in the male adult of the SE-Sel strain. Moreover, the expression of the juvenile hormone-binding proteins SeJHBWDS3 and SeJHBAN in the male adult of the SE-Sel strain was significantly decreased, which proved the existence of a fitness cost from another angle. Therefore, these results indicate that the fitness cost accompanied by chlorantraniliprole resistance in S. exigua may be related to the decrease in mating desire due to SeNPF overexpression.

PLoS Biology ◽  
2021 ◽  
Vol 19 (4) ◽  
pp. e3001190
Author(s):  
Rui Pang ◽  
Ke Xing ◽  
Longyu Yuan ◽  
Zhikun Liang ◽  
Meng Chen ◽  
...  

Chemical insecticides have been heavily employed as the most effective measure for control of agricultural and medical pests, but evolution of resistance by pests threatens the sustainability of this approach. Resistance-conferring mutations sometimes impose fitness costs, which may drive subsequent evolution of compensatory modifier mutations alleviating the costs of resistance. However, how modifier mutations evolve and function to overcome the fitness cost of resistance still remains unknown. Here we show that overexpression of P450s not only confers imidacloprid resistance in the brown planthopper, Nilaparvata lugens, the most voracious pest of rice, but also leads to elevated production of reactive oxygen species (ROS) through metabolism of imidacloprid and host plant compounds. The inevitable production of ROS incurs a fitness cost to the pest, which drives the increase or fixation of the compensatory modifier allele T65549 within the promoter region of N. lugens peroxiredoxin (NlPrx) in the pest populations. T65549 allele in turn upregulates the expression of NlPrx and thus increases resistant individuals’ ability to clear the cost-incurring ROS of any source. The frequent involvement of P450s in insecticide resistance and their capacity to produce ROS while metabolizing their substrates suggest that peroxiredoxin or other ROS-scavenging genes may be among the common modifier genes for alleviating the fitness cost of insecticide resistance.


Plants ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 469 ◽  
Author(s):  
Vila-Aiub

Herbicide resistance is the ultimate evidence of the extraordinary capacity of weeds to evolve under stressful conditions. Despite the extraordinary plant fitness advantage endowed by herbicide resistance mutations in agroecosystems under herbicide selection, resistance mutations are predicted to exhibit an adaptation cost (i.e., fitness cost), relative to the susceptible wild-type, in herbicide untreated conditions. Fitness costs associated with herbicide resistance mutations are not universal and their expression depends on the particular mutation, genetic background, dominance of the fitness cost, and environmental conditions. The detrimental effects of herbicide resistance mutations on plant fitness may arise as a direct impact on fitness-related traits and/or coevolution with changes in other life history traits that ultimately may lead to fitness costs under particular ecological conditions. This brings the idea that a “lower adaptive value” of herbicide resistance mutations represents an opportunity for the design of resistance management practices that could minimize the evolution of herbicide resistance. It is evident that the challenge for weed management practices aiming to control, minimize, or even reverse the frequency of resistance mutations in the agricultural landscape is to “create” those agroecological conditions that could expose, exploit, and exacerbate those life history and/or fitness traits affecting the evolution of herbicide resistance mutations. Ideally, resistance management should implement a wide range of cultural practices leading to environmentally mediated fitness costs associated with herbicide resistance mutations.


2013 ◽  
Vol 145 (3) ◽  
pp. 338-342 ◽  
Author(s):  
Henry Murillo ◽  
David W.A. Hunt ◽  
Sherah L. VanLaerhoven

AbstractSpecimens of Chrysodeixis chalcites (Esper) (Lepidoptera: Noctuidae) have been found in different municipalities in southwestern Ontario, Canada since 2008. This nonnative species occurs in tomato and green bean crops where it has the potential of becoming an important insect pest.


2003 ◽  
Vol 81 (5) ◽  
pp. 757-762 ◽  
Author(s):  
Edward B Mondor ◽  
Bernard D Roitberg

For an alarm signal to evolve, the benefits to the signaler must outweigh the costs of sending the signal. Research has largely focused on the benefits of alarm signaling, and the costs to an organism of sending an alarm signal are not well known. When attacked by a predator, aphids secrete cornicle droplets, containing an alarm pheromone, for individual protection and to warn clonemates. As aphid alarm pheromone is synthesized de novo in a feedback loop with juvenile hormone, we hypothesized that the secretion of cornicle droplets may result in a direct fitness cost to the emitter. We show that the secretion of a single cornicle droplet by pre-reproductive (third- and fourth-instar) pea aphids, Acyrthosiphon pisum, directly altered the timing and number of offspring produced. Third-instar pea aphids delayed offspring production but produced more offspring overall than non-secreting aphids, demonstrating a life-history shift but no significant fitness cost of droplet secretion. Fourth-instar pea aphids also delayed offspring production but produced the same number of offspring as non-secretors, resulting in a direct fitness cost of droplet secretion. Offspring production by adult, reproductive pea aphids that secreted a cornicle droplet did not differ from that of non-secretors. Thus, the fitness costs of secreting cornicle droplets containing an alarm signal are age-dependent.


2000 ◽  
Vol 349 (1) ◽  
pp. 323-332 ◽  
Author(s):  
François-Xavier BOITTIN ◽  
Frédéric COUSSIN ◽  
Jean-Luc MOREL ◽  
Guillaume HALET ◽  
Nathalie MACREZ ◽  
...  

Localized Ca2+-release signals (puffs) and propagated Ca2+ waves were characterized in rat ureteric myocytes by confocal microscopy. Ca2+ puffs were evoked by photorelease of low concentrations of Ins(1,4,5)P3 from a caged precursor and by low concentrations of acetylcholine; they were also observed spontaneously in Ca2+-overloaded myocytes. Ca2+ puffs showed some variability in amplitude, time course and spatial spread, suggesting that Ins(1,4,5)P3-gated channels exist in clusters containing variable numbers of channels and that within these clusters a variable number of channels can be recruited. Immunodetection of Ins(1,4,5)P3 receptors revealed the existence of several spots of fluorescence in the confocal cell sections, supporting the existence of clusters of Ins(1,4,5)P3 receptors. Strong Ins(1,4,5)P3 photorelease and high concentrations of acetylcholine induced Ca2+ waves that originated from an initiation site and propagated in the whole cell by spatial recruitment of neighbouring Ca2+-release sites. Both Ca2+ puffs and Ca2+ waves were blocked selectively by intracellular applications of heparin and an anti-Ins(1,4,5)P3-receptor antibody, but were unaffected by ryanodine and intracellular application of an anti-ryanodine receptor antibody. mRNAs encoding for the three subtypes of Ins(1,4,5)P3 receptor and subtype 3 of ryanodine receptor were detected in these myocytes, and the maximal binding capacity of [3H]Ins(1,4,5)P3 was 10- to 12-fold higher than that of [3H]ryanodine. These results suggest that Ins(1,4,5)P3-gated channels mediate a continuum of Ca2+ signalling in smooth-muscle cells expressing a high level of Ins(1,4,5)P3 receptors and no subtypes 1 and 2 of ryanodine receptors.


Insects ◽  
2020 ◽  
Vol 11 (9) ◽  
pp. 615
Author(s):  
Albasini Caniço ◽  
António Mexia ◽  
Luisa Santos

The alien invasive insect pest Spodoptera frugiperda Smith (Lepidoptera: Noctuidae), commonly referred to as fall armyworm (FAW), is causing significant losses to maize production in Africa since its detection in 2016. As an emergency response, governments in several countries distributed and/or promoted massive use of synthetic insecticides among smallholder farmers to fight FAW. The inappropriate use of synthetic insecticides by non-trained and ill-equipped farmers raises environmental and health concerns. This study aimed to assess the occurrence of native parasitoids of FAW, their parasitism rates, and relative abundance in the central province of Manica, Mozambique. A field collection of FAW egg masses and larvae was conducted from May to August 2019 (dry season of the 2018/2019 cropping season) and in December 2019 and January 2020 (rainy season of 2019/2020 cropping season). A total of 101 egg masses and 1444 larvae of FAW were collected from infested fields. Five larval parasitoids were recorded, but no egg parasitism was observed. Coccygidium luteum Brullé (Hymenoptera: Braconidae) and Drino quadrizonula Thomson (Diptera: Tachinidae) were the primary parasitoids. Maximum parasitism of 23.68% and 8.86% and relative abundance of 100 and 96.3 were recorded for C. luteum and D. quadrizonula, respectively. Total parasitism by different parasitoid species was at 9.49%. Cultural practices favoring the action of these parasitoids should be advocated.


2018 ◽  
Vol 47 (4) ◽  
pp. 927-934 ◽  
Author(s):  
Shengyuan Zhao ◽  
Xiaowei Fu ◽  
Jianglong Guo ◽  
Yan Zhou ◽  
Kris A G Wyckhuys ◽  
...  

Abstract The spotted clover moth, Protoschinia scutosa (Denis & Schiffermüller) (Lepidoptera: Noctuidae), is an important polyphagous pest that is widely distributed in the world. P. scutosa overwinters as pupae in agricultural soils in Northern China. Yet, it is unclear whether P. scutosa also engages in seasonal migration over mid- to long-range distances. In this study, we employ light trapping, field surveys, and ovarian dissection of captured adults over a 2003–2015 time period to assess P. scutosa migration in Northern China. Our work shows that P. scutosa migrates across the Bohai Strait seasonally; the mean duration of its windborne migration period was 121.6 d, and the mean trapping number was 1053.6 moths. Nightly catches of P. scutosa were significantly different between months, but the differences between years were not significant. During 2009–2011 and 2013, the monthly proportion of migrating females (65.5%) was significantly higher than that of males and showed no difference between months. In May to June, the majority of females (May: 63.0%; June: 61.1%) were mated individuals with relatively high level of ovarian development; however, in August and September, most females were unmated. The mean proportion of mated females was significantly different across months but did not differ between years. The results of long-term searchlight trapping and ovarian dissection indicate that P. scutosa exhibits a seasonal characteristic of typical population dynamics and reproductive development of migratory insects. Our work sheds light upon key facets of P. scutosa ecology and facilitates the future development of pest forecasting systems and pest management schemes.


1990 ◽  
Vol 38 (4) ◽  
pp. 347 ◽  
Author(s):  
GR Allen

A field study was undertaken to determine the phenologies of the solitary larval endoparasitoids Cotesia urabae and Dolichogenidea eucalypti in relation to that of their bivoltine host Uraba lugens. C. urabae had two generations within both the summer and the winter generation of U. lugens, and D. eucalypti had two generations in the summer but only one generation in the winter. D. eucalypti parasitised a narrower range of host sizes in the field. Both parasitoids attacked recently hatched (typically 1st instar) or 'small hosts' at the beginning at each host generation. In summer D. eucalypti was the first to emerge from hosts, but both D. eucalypti and C. urabae, emerged from hosts which had modes of 0.85-1.05 mm in head capsule width and 0.9-1.5 mg in dry weight (mid hosts). In winter, C. urabae emerged from hosts which had modes of 1.15 mm in head capsule width and 2.7 mg in dry weight (large hosts). Both species in summer, and C. urabae in winter, then proceeded to parasitise hosts of around these sizes to commence second parasitoid generations. In its second generation in summer and its first generation in winter, D. eucalypti typically emerged after most unparasitised hosts had pupated. Both species of parasitoid overwintered within the larval stage of their host. Levels of parasitisation appeared to be low, and dropped between first and second generations within each host generation. It was concluded that C. urabae and D. eucalypti displayed continuity of generations and a high level of synchronisation with U. lugens in the Adelaide region.


Sign in / Sign up

Export Citation Format

Share Document