Biology and thermal requirements of Telenomus remus reared on fall armyworm Spodoptera frugiperda eggs

This research aimed at studing Telenomus remus Nixon biology reared on Spodoptera frugiperda (J.E. Smith) eggs at different temperatures. Based on the development of the cycle (egg-adult), the thermal requirements and the number of parasitoid generations at constant temperatures were determined. Initially, 24-hour-old S. frugiperda eggs were submitted to parasitism by T. remus during 5 h, being then transferred to acclimatized chambers regulated at 15, 20, 25, 28, 31, and 35°C. The cycle (egg to adult) was influenced by temperature varying from 8.3±0.01 to 47.2±0.01 for females and 8.1±0.01 to 46.8±0.01 days for males at 31 and 15°C, respectively. The emergency (%) was also influenced by temperature. A reduction in emergency was observed at 15°C and no emergency at 35°C. T. remus sex ratio was not influenced by temperature. Sexual rate was not changed by temperature. Regarding to thermal requirements, thermal constant (K) and inferior thermal threshold (Tb) were higher for T. remus females (158.88 degree-days and 12.5°C) when compared to males (154.12 degree-days and 12.6°C). The estimated number of T. remus generation per year for males and females at laboratory conditions was 5.6 and 5.6, 16.9 and 17.3, 28.3 and 29.0, 35.1 and 36.0, 39.6 and 40.7 at 15, 20, 25, 28, and 31oC, respectively.

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Thermal requirements and estimated number of generations of Neopamera bilobata (Say) in strawberry-producing regions of Brazil

Ciência Rural ◽

10.1590/0103-8478cr20170212 ◽

2017 ◽

Vol 48 (1) ◽

Author(s):

Taciana Melissa de Azevedo Kuhn ◽

Alci Enimar Loeck ◽

Marcos Botton

Keyword(s):

Adult Stage ◽

Thermal Constant ◽

Rio Grande Do Sul ◽

Degree Days ◽

Climate Chamber ◽

Thermal Threshold ◽

Developmental Threshold ◽

Thermal Requirements ◽

Developmental Thresholds ◽

The Mean

ABSTRACT: The thermal threshold and thermal requirements of Neopamera bilobata were determined, and the number of generations that this species may produce in the main strawberry-producing regions of Brazil was estimated. In a climate chamber (70±10% RH and 12h photophase) at 16, 19, 22, 25, 28, or 30±1°C, the development of 120 eggs was monitored until the adult stage, at each temperature. Nymphs were maintained in individual cages and fed on strawberry fruits of the cultivar Aromas. The mean duration and viability of the egg and nymph stages were calculated by estimating the lower and upper developmental thresholds and the thermal constant, and this information was used to estimate the number of generations per year in different strawberry-producing regions of Brazil. The egg-to-adult duration decreased as temperatures increased, up to 28°C (93.4, 83.2, 43.9, and 31.4 days at 19, 22, 25, and 28°C, respectively). Viability of nymphs was highest between 22 and 28°C. At 30°C, the egg-to-adult duration increased (36 days), while the viability decreased (11.11%). The lower egg-to-adult developmental threshold was 15.2°C and the thermal constant was 418.4 degree-days. Calculating the number of generations indicated that the largest number (5.1 generations yr-1) was obtained for the municipality of Jaboti, Paraná, and the smallest for Caxias do Sul, Rio Grande do Sul (1.9 generations yr-1). Our findings demonstrated that important strawberry-producing regions in Brazil are suitable for the development of N. bilobata.

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The Effect of Temperature on the Development of Spodoptera frugiperda (Lepidoptera: Noctuidae)

Insects ◽

10.3390/insects11040228 ◽

2020 ◽

Vol 11 (4) ◽

pp. 228 ◽

Cited By ~ 5

Author(s):

Hannalene Du Plessis ◽

Marie-Louise Schlemmer ◽

Johnnie Van den Berg

Keyword(s):

Adult Development ◽

Spodoptera Frugiperda ◽

Far East ◽

Fall Armyworm ◽

Invasion Biology ◽

Larval Survival ◽

Development Rate ◽

Effect Of Temperature ◽

Temperature Threshold ◽

Different Temperatures

The fall armyworm (Spodoptera frugiperda) is a pest of tropical origin which recently invaded Africa, the Far East and Australia. Temperature, therefore, plays an important role in its invasion biology, since this pest does not go into diapause. The aim of this study was to determine the development rate of S. frugiperda at different temperatures and to calculate the number of degree-days (°D) required for each stage to complete its development. This study was conducted at five different temperatures—18, 22, 26, 30 and 32 ± 1 °C. Larvae were reared individually in Petri dishes with sweetcorn kernels provided as food. The development rate of S. frugiperda increased linearly with increasing temperatures between 18 and 30 °C and larval survival was the highest between 26 and 30 °C. The optimal range for egg, larval and egg-to-adult development was between 26 and 30 °C. The optimum temperature with the fastest larval development rate and lowest mortality was at 30 °C. The pupal development period ranged between 7.82 and 30.68 days (32–18 °C). The minimum temperature threshold for egg and larva development was 13.01 and 12.12 °C, respectively, 13.06 °C for pupae and 12.57 °C for egg-to-adult development. Degree-day requirements for the development of the respective life cycle stages of S. frugiperda were 35.68 ± 0.22 for eggs, 204.60 ± 1.23 °D for larvae, 150.54 ± 0.93 °D for pupae and 391.61 ± 1.42 °D for egg-to-adult development.

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THE INFLUENCE OF CONSTANT TEMPERATURES ON THE NON-DIAPAUSE DEVELOPMENT OF HYSSOPUS THYMUS (HYMENOPTERA: EULOPHIDAE)

The Canadian Entomologist ◽

10.4039/ent104113-1 ◽

1972 ◽

Vol 104 (1) ◽

pp. 113-120 ◽

Cited By ~ 1

Author(s):

Paul D. Syme

Keyword(s):

Developmental Stages ◽

Climatic Conditions ◽

Thermal Constant ◽

Regression Equations ◽

Degree Days ◽

Different Temperatures ◽

Potential Impact ◽

Diapause Development ◽

The Relationship ◽

Fluctuating Temperatures

AbstractThe influence of constant temperatures on the non-diapause development of Hyssopus thymus was studied and the results of these studies are presented. A lower threshold for development of less than 12 °C and an upper threshold of about 32 °C were determined. Mean times for and rates of development at different temperatures are presented for all developmental stages. The egg is the stage most sensitive to temperature change. Regression equations describing the relationship between the rate of development and temperature for these stages are given and a thermal constant (K) of about 190 degree-days is calculated for total development. This constant is not applicable to naturally fluctuating temperatures. The results of these studies are discussed in relation to the potential impact of H. thymus on European pine shoot moth dynamics under different climatic conditions. It is concluded that H. thymus should be more effective in warmer seasons and at lower latitudes.

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Thermal Requirements of Ooencyrtus submetallicus (Hym.: Encyrtidae) and Telenomus podisi (Hym.: Platygastridae) Parasitizing Euschistus heros Eggs (Hem.: Pentatomidae)

Insects ◽

10.3390/insects12100924 ◽

2021 ◽

Vol 12 (10) ◽

pp. 924

Author(s):

Valeria Freitas Chaves ◽

Fabricio Fagundes Pereira ◽

Jorge Braz Torres ◽

Ivana Fernandes da Silva ◽

Patrik Luiz Pastori ◽

...

Keyword(s):

Abiotic Factors ◽

Thermal Constant ◽

Cycle Duration ◽

Base Temperature ◽

Thermal Requirements ◽

Euschistus Heros ◽

Different Temperatures ◽

Telenomus Podisi ◽

And Behavior ◽

Number Of Individuals

Temperature is one of the abiotic factors that strongly influences the biology and behavior of insects. In this study, we assessed the development of egg parasitoids Ooencyrtus submetallicus and Telenomus podisi parasitizing Euschistus heros eggs at different temperatures, and estimated the average number of generations for seven representative soybean-producing regions in Brazil. A comparative biology study was conducted, where the percentage of parasitism and emergence, life cycle duration (egg–adult), and longevity were found to be similar between O. submetallicus and T. podisi. The sex ratio and the number of individuals emerged from parasitized egg were higher in O. submetallicus in all regions. In the study of thermal requirements, temperatures of 16, 19, 22, 25, 28, 31, and 33 °C were tested. O. submetallicus and T. podisi developed at temperatures between 16 and 31 °C. The base temperature (Tb) for O. submetallicus and T. podisi was 9.3 and 6.7 °C, respectively; the thermal constant (K) was 336.9 and 272.7 degree-days, respectively. The estimated average number of annual generations of both parasitoids was higher than the host. O. submetallicus and T. podisi have the same ability to parasitize and develop in eggs of E. heros under the conditions studied. Both parasitoids exhibited satisfactory development and parasitism at temperatures between 19 and 31 °C. The development of both parasitoids was faster than their host, and the number of generations was higher for the seven studied localities.

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Telenomus remus, a Candidate Parasitoid for the Biological Control of Spodoptera frugiperda in Africa, is already Present on the Continent

Insects ◽

10.3390/insects10040092 ◽

2019 ◽

Vol 10 (4) ◽

pp. 92 ◽

Cited By ~ 20

Author(s):

Marc Kenis ◽

Hannalene du Plessis ◽

Johnnie Van den Berg ◽

Malick Ba ◽

Georg Goergen ◽

...

Keyword(s):

Biological Control ◽

Spodoptera Frugiperda ◽

Fall Armyworm ◽

Classical Biological Control ◽

Egg Parasitoid ◽

Sub Saharan Africa ◽

Great Opportunity ◽

Augmentative Biological Control ◽

Sub Saharan ◽

Telenomus Remus

The fall armyworm, Spodoptera frugiperda, a moth originating from tropical and subtropical America, has recently become a serious pest of cereals in sub-Saharan Africa. Biological control offers an economically and environmentally safer alternative to synthetic insecticides that are being used for the management of this pest. Consequently, various biological control options are being considered, including the introduction of Telenomus remus, the main egg parasitoid of S. frugiperda in the Americas, where it is already used in augmentative biological control programmes. During surveys in South, West, and East Africa, parasitized egg masses of S. frugiperda were collected, and the emerged parasitoids were identified through morphological observations and molecular analyses as T. remus. The presence of T. remus in Africa in at least five countries provides a great opportunity to develop augmentative biological control methods and register the parasitoid against S. frugiperda. Surveys should be carried out throughout Africa to assess the present distribution of T. remus on the continent, and the parasitoid could be re-distributed in the regions where it is absent, following national and international regulations. Classical biological control should focus on the importation of larval parasitoids from the Americas.

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Telenomus remus (Hymenoptera: Platygastridae) parasitism on Spodoptera frugiperda (Lepidoptera: Noctuidae) eggs: different parasitoid and host egg ages

Semina Ciências Agrárias ◽

10.5433/1679-0359.2019v40n6supl2p2933 ◽

2019 ◽

Vol 40 (6Supl2) ◽

pp. 2933

Author(s):

Ana Paula de Queiroz ◽

Bruna Magda Favetti ◽

Pamela Gislaine Luski ◽

Jaciara Gonçalves ◽

Pedro Manuel Oliveira Janeiro Neves ◽

...

Keyword(s):

Sex Ratio ◽

Spodoptera Frugiperda ◽

Choice Test ◽

Host Age ◽

Lack Of Information ◽

Randomized Design ◽

Completely Randomized Design ◽

Lepidoptera Noctuidae ◽

Old Females ◽

Telenomus Remus

Abstract: Release of egg parasitoids for biological control of pests is a promising technique in integrated pest management (IPM). However, there is a lack of information on the performance of parasitoid females of different ages, and specifically on the behavior of the parasitoid Telenomus remus towards pest eggs at different stages of embryonic development. Thus, the relationships between host age, parasitoid age, and parasitism by T. remus on Spodoptera frugiperda eggs were evaluated. Three separate bioassays were performed, each in a completely randomized design. In the first bioassay, T. remus females grouped by age in days (ranging from 1 to 10 days old) were offered 100 ± 20 eggs of S. frugiperda for 24 hours. In the second bioassay, 100 ± 20 eggs of S. frugiperda (24, 48 or 72 hours old) were offered to females of T. remus for 24 hours. In the third bioassay, 24, 48- and 72-hour-old host eggs of S. frugiperda were offered to T. remus females in a choice test. The variables evaluated were: number of parasitized eggs, parasitoid emergence (%), and sex ratio of progeny in bioassays 1 and 2, and the number of eggs parasitized in bioassay 3. The age of T. remus females did not affect the number of S. frugiperda eggs parasitized or emergence of the progeny. However, the sex ratio was more male-biased in the progeny of 1- and 2-day-old females compared to older wasps. In bioassay 2, the highest parasitism was observed in 24- and 48-hour-old eggs. Percentage emergence and sex ratios were not influenced by the ages of the eggs tested. Telenomus remus preferred to parasitize 24-hour-old eggs in bioassays 3. Overall, the age of T. remus females tested did not affect the parasitism of S. frugiperda eggs, but the number of eggs parasitized decreased with increasing host age.

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Natural Enemies of Fall Armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) in Different Agro-Ecologies

Insects ◽

10.3390/insects12060509 ◽

2021 ◽

Vol 12 (6) ◽

pp. 509

Author(s):

Albert Fomumbod Abang ◽

Samuel Nanga Nanga ◽

Apollin Fotso Kuate ◽

Christiant Kouebou ◽

Christopher Suh ◽

...

Keyword(s):

Natural Enemies ◽

Spodoptera Frugiperda ◽

Development Time ◽

Fall Armyworm ◽

Spodoptera Eridania ◽

Southern Armyworm ◽

Parasitism Rates ◽

Emergency Actions ◽

Indigenous Natural Enemies ◽

Telenomus Remus

Fall armyworm (FAW) Spodoptera frugiperda (J.E. Smith) and southern armyworm (SAW) Spodoptera eridania (Stoll) have become major threats to crops in Africa since 2016. African governments adopted emergency actions around chemical insecticides, with limited efforts to assess the richness or roles of indigenous natural enemies. Field surveys and laboratory studies were conducted to identify and assess the performance of parasitoids associated with spodopterans in Cameroon. FAW was the most abundant spodopteran pest. Telenomus remus (Nixon), Trichogramma chilonis (Ishi), Charops sp. (Szépligeti), Coccygidium luteum (Cameron), Cotesia icipe (Fernandez & Fiaboe), and Cotesia sesamiae (Cameron) are the first records in the country on spodopterans. Telenomus remus, T. chilonis, C. icipe, and Charops sp. were obtained from both FAW and SAW; C. luteum and C. sesamiae from FAW. The distribution of spodopterans, their endoparasitoids, and parasitism rates varied with host, season and location. In the laboratory, T. remus showed significantly higher parasitism on FAW than SAW, and significant differences in the development parameters between the two host eggs, with shorter development time on FAW. It induced significant non-reproductive mortality on FAW but not on SAW. Developmental parameters showed that C. icipe has a shorter development time compared to other larval parasitoids. Implications for conservative and augmentative biocontrol are discussed.

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First report of Telenomus remus parasitizing Spodoptera frugiperda and its field parasitism in southern China

Journal of Hymenoptera Research ◽

10.3897/jhr.73.39136 ◽

2019 ◽

Vol 73 ◽

pp. 95-102 ◽

Cited By ~ 1

Author(s):

Yong-Lin Liao ◽

Bin Yang ◽

Miao-Feng Xu ◽

Wei Lin ◽

De-Sen Wang ◽

...

Keyword(s):

Biological Control ◽

Spodoptera Frugiperda ◽

Southern China ◽

Management Strategies ◽

Fall Armyworm ◽

Invasive Pest ◽

Egg Mass ◽

Molecular Evidence ◽

Parasitism Rates ◽

Telenomus Remus

The fall armyworm, Spodoptera frugiperda, is a lepidopteran pest that feeds on many economically important cereal crops such as corn, rice, sorghum, and sugarcane. Native to the Americas, it has become a serious invasive pest in Africa and Asia. Recently, this pest was found in China and has spread quickly across the country. As S. frugiperda will most likely become a major pest in China, Integrated Pest Management strategies, including biological control methods, should be developed to manage its populations. Here, we report the detection of Telenomus remus parasitizing S. frugiperda eggs in cornfields in southern China based on morphological and molecular evidence. Our preliminary surveys indicated that the parasitism rates of T. remus on S. frugiperda could reach 30% and 50% for egg masses and per egg mass, respectively. Further application of T. remus against S. frugiperda in biological control programs are discussed.

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Occurrence of natural enemies of fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae) in Nigeria

PLoS ONE ◽

10.1371/journal.pone.0254328 ◽

2021 ◽

Vol 16 (7) ◽

pp. e0254328

Author(s):

Akindele Oluwole Ogunfunmilayo ◽

Shakiru Adewale Kazeem ◽

Joy Ejemen Idoko ◽

Raphael Abiodun Adebayo ◽

Elizabeth Yetunde Fayemi ◽

...

Keyword(s):

Natural Enemies ◽

Spodoptera Frugiperda ◽

Management Strategies ◽

Fall Armyworm ◽

Parasitic Mite ◽

Maize Plants ◽

Staple Crop ◽

Lepidoptera Noctuidae ◽

Eggs And Larvae ◽

Telenomus Remus

Fall armyworm (FAW; Spodoptera frugiperda), an exotic moth which recently invaded Africa, is a highly destructive pest of cereals especially maize a highly valued staple crop in Nigeria. The use of natural enemies such as predators or parasitoids for FAW control is more economically viable and environmentally safer than currently recommended synthetic insecticides. Natural enemies to combat the pest have not yet been reported in Nigeria. An exploration for the pests’ natural enemies was undertaken by collecting FAW eggs and larvae from maize fields. These were reared in the laboratory for emergence, identification and efficacy as natural enemies. This yielded Euplectrus laphygmae (Hymenoptera: Eulophidae); Telenomus remus (Hymenoptera: Platygastridae) and Trombidium sp. (Acari.: Trombidiidae). Cotesia or Apanteles spp. were inferred to occur since Stictopisthus sp. (Hym.: Ichneumonidae), a secondary parasitoid, that attacks cocoons of Microgasterinae (e.g. Cotesia, Apanteles etc.) also emerged. Species of yet-to-be identified predators were also observed in various niches of maize plants. A positive relationship was found between FAW instar and the number of E. laphygmae eggs/instar ranging, on average, from 1.5 on second instar to 5.5 on fourth instars hosts. Parasitism rate of T. remus on FAW eggs was 100%. Parasitic mite infestation resulted in increasing paleness, reduced feeding, growth and movement as well as death of FAW 1st instars. Thus, the occurrence of FAW natural enemies in Nigeria calls for advocacy campaign to incorporate their use into integrated pest management strategies that attract and allow natural enemies to thrive for FAW management.

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Larval and pupal stage of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in sweet and field corn genotypes

Brazilian Journal of Biology ◽

10.1590/s1519-69842003000400009 ◽

2003 ◽

Vol 63 (4) ◽

pp. 627-633 ◽

Cited By ~ 6

Author(s):

L. M. Santos ◽

L. R. Redaelli ◽

L. M. G. Diefenbach ◽

C. F. S. Efrom

Keyword(s):

Sex Ratio ◽

Spodoptera Frugiperda ◽

Sweet Corn ◽

Fall Armyworm ◽

Pupal Stage ◽

Phase Duration ◽

Larval Phase ◽

Field Corn ◽

Lack Of Information ◽

And Control

Spodoptera frugiperda, the fall armyworm, is a very significant polyphagous pest due to the damages it causes, and control difficulties. Lack of information about its impact on sweet corn motivated a comparison of its biology, with respect to the larval and pupal stages, among the genotypes ELISA, BR 400 (sweet corns), and BR PAMPA (field corn). In laboratory conditions (25 ± 1ºC; 70 ± 10% RH; photophase 12 hours), 35 caterpillars were individualized and fed daily with 3.14 cm² sections of corn leaves from the referred-to genotypes, cultivated in plots in the experimental area of the Departament of Fitossanidade, UFRGS, Porto Alegre, RS from October to November 2000. The caterpillars were weighed daily; after each molt, the cephalic capsules were collected and measured (in width), to establish growth rate; pupae were weighed and sexed when 24 hours old. The duration of the larval instars, the pupal sex ratio, and the mortality of larvae and pupae were evaluated. In the first three instars there were no differences registered in capsule width. In the fourth and fifth instars, capsules of caterpillars kept in BR 400 were smaller. The weight of caterpillars and pupae, instar duration and sex ratio did not differ among the genotypes. Pupal phase duration was less in females kept in BR 400. Mortality was greater in the larval phase in ELISA and in the pupal phase in BR PAMPA.

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