scholarly journals Estimating the differences in critical thermal maximum and metabolic rate of Helicoverpa punctigera (Wallengren) (Lepidoptera: Noctuidae) across life stages

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12479
Author(s):  
Samuel A. Bawa ◽  
Peter C. Gregg ◽  
Alice P. Del Soccoro ◽  
Cara Miller ◽  
Nigel R. Andrew

Temperature is a crucial driver of insect activity and physiological processes throughout their life-history, and heat stress may impact life stages (larvae, pupae and adult) in different ways. Using thermolimit respirometry, we assessed the critical thermal maxima (CTmax-temperature at which an organism loses neuromuscular control), CO2 emission rate (V́CO2) and Q10 (a measure of V́CO2 temperature sensitivity) of three different life stages of Helicoverpa punctigera (Wallengren) by increasing their temperature exposure from 25 °C to 55 °C at a rate of 0.25 °C min−1. We found that the CTmax of larvae (49.1 °C ± 0.3 °C) was higher than pupae (47.4 °C ± 0.2 °C) and adults (46.9 °C ± 0.2 °C). The mean mass-specific CO2 emission rate (ml V́CO2 h−1) of larvae (0.26 ± 0.03 ml V́CO2 h−1) was also higher than adults (0.24 ± 0.04 ml V́CO2 h−1) and pupae (0.06 ± 0.02 ml V́CO2 h−1). The Q10: 25–35 °C for adults (2.01 ± 0.22) was significantly higher compared to larvae (1.40 ± 0.06) and Q10: 35–45 °C for adults (3.42 ± 0.24) was significantly higher compared to larvae (1.95 ± 0.08) and pupae (1.42 ± 0.98) respectively. We have established the upper thermal tolerance of H. punctigera, which will lead to a better understanding of the thermal physiology of this species both in its native range, and as a pest species in agricultural systems.

2008 ◽  
Vol 98 (6) ◽  
pp. 599-603 ◽  
Author(s):  
G.T. Behere ◽  
W.T. Tay ◽  
D.A. Russell ◽  
P. Batterham

AbstractThe four significant pest species in theHelicoverpagenus (H. armigera, H. assulta,H. punctigeraandH. zea) are morphologically similar and can only be reliably distinguished through dissection of adult genitalia. Two partial regions of the mitochondrial DNA (mtDNA), the cytochrome oxidase subunit I (COI) and the cytochromeb(Cytb) genes were amplified by PCR and digested with restriction endonucleases. The restriction patterns, generated by the endonucleasesBstZ17I andHphI, demonstrated reliable differentiation of the fourHelicoverpapest species. This technique is fast, reliable and effective at distinguishing specimens irrespective of their life stages and offers support to conventional taxonomic differentiation based on morphological characters.


1985 ◽  
Vol 75 (1) ◽  
pp. 169-184 ◽  
Author(s):  
Joanne C. Daly ◽  
Peter Gregg

AbstractGenetic (electrophoretic) variation was examined in the two pest species of Heliothis found in Australia, H. armigera (Hübner) and H. punctigera Wallengren. They could be differentiated by seven loci which enabled identification of individual eggs and small larvae not normally distinguishable by their morphology. The traditional criteria for distinguishing the larger larvae of the two species were shown to be unreliable. The genetic distance between the two species was 0·34 ± 0·02. The percentage of loci polymorphic in both species, 32%, and the mean heterozygosities, 11·3% for H. armigera and 10·8% for H. punctigera, are lower than those reported in the American species, H. virescens (F.) and H. zea (Boddie). Populations throughout Australia were differentiated from each other, but there did not appear to be a marked geographic pattern to the variation. Genetic distances between populations of H. armigera were low (<0·01). It was concluded that the effective population size of Heliothis is large and that significant gene flow probably occurs between widely separated regions.


2020 ◽  
Vol 3 (1) ◽  
pp. ACCEPTED
Author(s):  
Rho-Jeong Rae

This study investigated the boreal digging frog, Kaloula borealis, to determine the egg hatching period and whether the hatching period is affected by incubation temperature. The results of this study showed that all the eggs hatched within 48 h after spawning, with 28.1% (±10.8, n=52) hatching within 24 h and 99.9% (±0.23, n=49) within 48 h after spawning. A significant difference was noted in the mean hatching proportion of tadpoles at different water temperatures. The mean hatching rates between 15 and 24 h after spawning was higher at a water temperature of 21.1 (±0.2) °C than at 24.1 (±0.2) °C. These results suggest that incubation temperature affected the early life stages of the boreal digging frog, since they spawn in ponds or puddles that form during the rainy season.


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Ghulam Sarwar ◽  
Naeem Arshad Maan ◽  
Muhammad Ahsin Ayub ◽  
Muhammad Rafiq Shahid ◽  
Mubasher Ahmad Malik ◽  
...  

Abstract Background The armyworms, Spodoptera exigua (Hübner), and S. litura (Fabricius) (Lepidoptera: Noctuidae) are polyphagous pests of many cash crops. Heavy crop losses have been reported for the fruit and vegetable crops each year owing to the diverse impact on global economies. The present study was aimed to sort out a novel method of pest control using the insect’s own nucleopolyhedrosis virus (NPV) alone and in combination with a new chemistry insecticide chlorantraniliprole. Results In the study, the effect of indigenous isolated nucleopolyhedrovirus (NPV) and the chemical insecticide (chlorantraniliprole) formulations against the 2nd and 4th larval instars of S. litura and S. exigua, collected from the different geographical region of Punjab (Pakistan) province, was evaluated. Three concentrations of the NPV isolate, sub-lethal (1 × 104, 6 × 104 POB ml−1), lethal (3 × 105 POB ml−1), and chlorantraniliprole 0.01 μl l−1, were applied alone and in combination against the 2nd and 4th larval instars of both pest species. The lethal concentration of NPV + chlorantraniliprole exhibited synergistic interaction and caused high larval mortality against both instars, while in all other combinations, additive effect was observed. Moreover, NPV + chlorantraniliprole at lethal concentration exhibited decreased pupation, adult emergence, and egg eclosion. Conclusion The implications of using NPV alone and in combination with an insecticide are discussed briefly in this study.


2015 ◽  
Vol 68 ◽  
pp. 367-372
Author(s):  
M.M. Davidson ◽  
B.G. Howlett ◽  
R.C. Butler ◽  
N.M. Taylor ◽  
M.K. Walker

Shelterbelts of Pinus radiata and Cupressus macrocarpa are common landscape features on arable farmland in New Zealand This study aimed to determine whether such shelterbelts could influence the relative abundance and diversity of beneficial and pest invertebrates commonly found in arable crops Window intercept yellow sticky and pitfall traps were placed next to shelterbelts or post and wire fences and also 50 m from these borders into adjacent crops on two arable farms in Canterbury and one in Wairarapa over 12 weeks in summer 2012 and autumn 2013 The abundance of given species/taxa varied considerably depending on farm location season and field border type However the mean number of beneficial insect species/taxa per trap did not vary markedly between field border types or adjacent crops while traps at shelterbelts or their adjacent crops caught more of some pest species/taxa than traps beside fences The pine/macrocarpa shelterbelts did not markedly increase relative abundance or diversity of beneficial insects


Zootaxa ◽  
2018 ◽  
Vol 4420 (2) ◽  
pp. 243
Author(s):  
REZA HOSSEINI ◽  
KHADIJEH MADAHI

Many species of cutworms (Lepidoptera: Noctuidae) are important agricultural pest. They feed on roots and foliage of their host plants. Traditionally these species are identified based on morphological characteristics of adults. Hence identification of specimens in poor condition, immature stages and also closely related species or cryptic species is a difficult task. The basics of biological and ecological studies largely rely on an accurate species identification; consequently these investigations are impacted by potential misidentifications. In this study, we amplified 5' region of mitochondrial c cytochrome oxidase subunit I (COI) gene (DNA barcode region) of various common true cutworm species including Agrotis ipsilon (Hufnagel, 1766), Agrotis exclamationis (Linnaeus, 1758), Peridroma saucia (Hübner, 1808) and Xestia c-nigrum (Linnaeus, 1758) from agricultural fields of Guilan province (North of Iran). We were able to detect 66 conservative Single Nucleotide Polymorphisms (SNPs) among the targeted pest species and eventually design specific primers and develop a multiplex polymerase chain reaction assay as a molecular diagnostic tool for immature stages of two the most common and abundant species including A. ipsilon and X. c-nigrum in Guilan province. 


2001 ◽  
Vol 61 (4) ◽  
pp. 661-666 ◽  
Author(s):  
J. A. TESTON ◽  
A. SPECHT ◽  
E. CORSEUIL

Larvae of Anicla infecta (Ochsenheimer, 1816) (Noctuidae) feed upon many grasses and may be harmful to cereals and fodder of economic importance. This study was developed aiming to contribute to knowledge of the biology of this species. The rearing was done in an environmental chamber with the following settings: temperature of 25 ± 1ºC; relative humidity of 70% <FONT FACE=Symbol>±</FONT> 10%, and photoperiod of L14: D10. The larvae fed on ryegrass, Lolium multiflorum Lam. The results express the mean and standard error for the length of every stage in days. For each stage we observed the following time of development: egg 3.2 <FONT FACE=Symbol>±</FONT> 0.09; larvae 18.7 <FONT FACE=Symbol>±</FONT> 0.07; pre-pupae 3.3 <FONT FACE=Symbol>±</FONT> 0.04; pupae 12.6 <FONT FACE=Symbol>±</FONT> 0.14; and adult longevity was 12.1 <FONT FACE=Symbol>±</FONT> 1.03. Also the pre-egg-laying period was 4.4 <FONT FACE=Symbol>±</FONT> 0.59; the egg-laying period was 8.1 <FONT FACE=Symbol>±</FONT> 0.84; and the post-egg-laying period was 0.3 <FONT FACE=Symbol>±</FONT> 0.14. The mean number of egg-laying cycles per female was 6.7 <FONT FACE=Symbol>±</FONT> 0.73; that of eggs per cycle was 77.5 <FONT FACE=Symbol>±</FONT> 4.37; and total eggs per female was 521.4 <FONT FACE=Symbol>±</FONT> 47.36.


2019 ◽  
Vol 9 (5) ◽  
pp. 2933-2944 ◽  
Author(s):  
Tom K. Walsh ◽  
Omaththage Perera ◽  
Craig Anderson ◽  
Karl Gordon ◽  
Cecilia Czepak ◽  
...  

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.


2008 ◽  
Vol 98 (3) ◽  
pp. 317-322 ◽  
Author(s):  
V. Caron ◽  
J.H. Myers

AbstractDevelopment of resistance to insecticides has generally been associated with fitness costs that may be magnified under challenging conditions. Lepidopterans which are resistant to the biopesticide Bacillus thuringiensis subsp. kurstaki (Btk) have been shown to have reduced fitness, such as lower survival when subjected to overwintering stress. Recently, resistance to Btk has been found in some populations of Trichoplusia ni Hübner in greenhouses in British Columbia. This situation provides an opportunity to investigate potential trade-offs between overwintering survival and insecticide resistance in a major pest species. Here, we assess the survival and eventual fecundity of Btk resistant and susceptible T. ni pupae exposed to cool temperatures. Contrary to our expectations, resistant T. ni had higher overwintering survival than susceptible individuals. This is the first account of a potential advantage associated with Btk resistance. Resistant and susceptible moths had reduced fecundity and smaller progeny after cold exposure compared to controls, and this may counteract the survival advantage. Nevertheless, it seems unlikely that this is sufficient to select out the resistant phenotype in the presence of strong selection for resistance and in the absence of immigration of susceptible moths. The appearance of resistance without evidence of a trade-off in overwintering survival presents a major challenge to management in production greenhouses.


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