Assessing the Potential of Inoculative Field Releases of Telenomus remus to Control Spodoptera frugiperda in Ghana

In response to the threat caused by the fall armyworm to African maize farmers, we conducted a series of field release studies with the egg parasitoid Telenomus remus in Ghana. Three releases of ≈15,000 individuals each were conducted in maize plots of 0.5 ha each in the major and minor rainy seasons of 2020, and compared to no-release control plots as well as to farmer-managed plots with chemical pest control. No egg mass parasitism was observed directly before the first field release. Egg mass parasitism reached 33% in the T. remus release plot in the major rainy season, while 72–100% of egg masses were parasitized in the minor rainy season, during which pest densities were much lower. However, no significant difference in egg mass parasitism was found among the T. remus release plots, the no-release control plots and the farmer-managed plots. Similarly, no significant decrease in larval numbers or plant damage was found in the T. remus release fields compared to the no-release plots, while lower leaf and tassel damage was observed in farmer-managed plots. Larval parasitism due to other parasitoids reached 18–42% in the major rainy season but was significantly lower in the minor rainy season, with no significant differences among treatments. We did not observe significant differences in cob damage or yield among the three treatments. However, the lack of any significant differences between the release and no-release plots, which may be attributed to parasitoid dispersal during the five weeks of observation, would require further studies to confirm. Interestingly, a single application of Emamectin benzoate did not significantly affect the parasitism rates of T. remus and, thus, merits further investigation in the context of developing IPM strategies against FAW.

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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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Ephestia kuehniella Zeller as a Factitious Host for Telenomus remus Nixon: Host Acceptance and Suitability

Journal of Entomological Science ◽

10.18474/0749-8004-37.1.10 ◽

2002 ◽

Vol 37 (1) ◽

pp. 10-26 ◽

Cited By ~ 4

Author(s):

Laura Martínez-Martínez ◽

Julio S. Bernal

Keyword(s):

Fall Armyworm ◽

Egg Parasitoid ◽

Accessory Gland ◽

Ephestia Kuehniella ◽

Egg Load ◽

Host Acceptance ◽

Adult Size ◽

Parasitism Rates ◽

Novel Host ◽

Telenomus Remus

Telenomus remus Nixon is an egg parasitoid used against fall armyworm, Spodoptera frugiperda (J. E. Smith), in various countries of the Americas. The feasibility of rearing T. remus at lower cost and greater efficiency on a novel host, Ephestia kuehniella Zeller, was addressed in a two-part study. The first part of the study compared acceptance of eggs of E. kuehniella, fall armyworm, and E. kuehniella with a kairomone from the accessory gland of fall armyworm females. Acceptance was assessed as residence time on eggs and parasitism rates. Females of T. remus spent more time and showed higher parasitism rates on eggs of fall armyworm followed by those of E. kuehniella with kairomone, and E. kuehniella. The second part of the study compared the suitability of eggs of fall armyworm versus eggs of E. kuehniella for development of T. remus. Suitability was assessed by comparing various fitness components between parasitoids reared on fall armyworm and E. kuehniella. Compared to T. remus reared on eggs of fall armyworm, those reared on eggs of E. kuehniella had longer egg to adult developmental times, shorter longevities, and reduced egg loads and adult sizes. In contrast, significant differences were not evident in levels of fluctuating asymmetry (lengths of hind tibiae and distances between apices of stigmata and hamular folds of forewings) between T. remus reared on eggs of fall armyworm or E. kuehniella. Longevity was not significantly correlated with adult size, or the correlation was poor, whereas egg load and adult size were significantly correlated in females reared both on fall armyworm and E. kuehniella.

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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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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 natural parasitism in South China

10.1101/697920 ◽

2019 ◽

Author(s):

Yong-Lin Liao ◽

Bin Yang ◽

Miao-Feng Xu ◽

Wei Lin ◽

De-Sen Wang ◽

...

Keyword(s):

Biological Control ◽

South China ◽

Spodoptera Frugiperda ◽

Management Strategies ◽

Invasive Pest ◽

Egg Mass ◽

Molecular Evidence ◽

Parasitism Rates ◽

Telenomus Remus ◽

Natural Parasitism

AbstractThe 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 invaded China and has spread exceptionally fast 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 win the battle against it. Here, we report the detection of Telenomus remus parasitizing S. frugiperda eggs in cornfields in South China based on morphological and molecular evidence. Our preliminary surveys indicated that the natural 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, Seasonal Abundance, and Superparasitism of Ooencyrtus kuvanae (Hymenoptera: Encyrtidae) as an Egg Parasitoid of the Spotted Lanternfly (Lycorma delicatula) in North America

Forests ◽

10.3390/f10020079 ◽

2019 ◽

Vol 10 (2) ◽

pp. 79 ◽

Cited By ~ 6

Author(s):

Houping Liu

Keyword(s):

North America ◽

Biological Control Agent ◽

Egg Parasitoid ◽

Seasonal Abundance ◽

Egg Mass ◽

Laboratory Incubation ◽

Significant Difference ◽

Lycorma Delicatula ◽

Ooencyrtus Kuvanae ◽

Oviposition Sites

The occurrence of egg parasitoid Ooencyrtus kuvanae (Howard) (Hymenoptera: Encyrtidae) on its new host, the spotted lanternfly (Lycorma delicatula (White) (Hemiptera: Fulgoridae)), was surveyed at 4 study plots in 2016 and 10 additional plots in 2017 in Pennsylvania through field collection and laboratory incubation. O. kuvanae adults were found on L. delicatula egg mass surfaces at two plots (ODSouth and Lutz) in 2016, but at none in 2017. The results of laboratory incubation showed that O. kuvanae adults were only recovered from host eggs collected at plot ODSouth in 2016, with adults emerging between 22 April and 2 May 2016 at 22 ± 1 °C, 40% ± 5% relative humidity (RH), and a 16:8 h photoperiod (light/dark). The overall parasitism at this study plot was 6.0% by egg mass and 1.2% by egg. Two oviposition sites contained parasitized L. delicatula eggs, with 12.3% (9.5–15.0%) host egg masses and 3.1% (1.3–5.0%) host eggs utilized by the parasitoid. O. kuvanae parasitism by egg was significantly higher on oviposition site ODSouth #7 than on ODSouth #8. No O. kuvanae adults were reared out of field-collected host eggs from the 10 plots in 2017. Seasonal abundance and superparasitism of O. kuvanae was examined at plot ODSouth in 2017. O. kuvanae-parasitized L. delicatula eggs were found on all four oviposition sites based on field monitoring of parasitoid adult emergence, resulting in a parasitism of 35.4% (18.8–55.6%) by egg mass and 2.2% (0.5–3.9%) by egg. No significant difference in parasitism by egg was observed among oviposition sites. O. kuvanae adults emerged in the field between 2 May and 1 June 2017. Superparasitism was confirmed for O. kuvanae on L. delicatula eggs based on parasitoid production (1.0–3.3 adults/parasitized egg) and adult exit holes (1–3 exit holes/parasitized egg). As the first parasitoid recorded from L. delicatula in North America, O. kuvanae has the potential to become an important biological control agent for L. delicatula in North America, with its well-synchronized life history in the spring, century-long field establishment, superparasitism, and female-biased progeny population. L. delicatula complements the gypsy moth well as an alternative host for O. kuvanae in the field.

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The use of Telenomus remus (Nixon, 1937) (Hymenoptera: Scelionidae) in the management of Spodoptera spp.: potential, challenges and major benefits

CABI Agriculture and Bioscience ◽

10.1186/s43170-021-00071-6 ◽

2022 ◽

Vol 3 (1) ◽

Author(s):

Yelitza Coromoto Colmenarez ◽

Dirk Babendreier ◽

Francisco Ramón Ferrer Wurst ◽

Carlos Luis Vásquez-Freytez ◽

Adeney de Freitas Bueno

Keyword(s):

Biological Control ◽

Fall Armyworm ◽

Control Program ◽

Mass Rearing ◽

Egg Parasitoid ◽

Crop Damage ◽

Rearing Techniques ◽

Global Threat ◽

Lepidoptera Noctuidae ◽

Telenomus Remus

AbstractSpodoptera frugiperda (Smith, 1797) (Lepidoptera: Noctuidae), also known as fall armyworm (FAW) is a polyphagous pest which can cause significant losses and is considered a global threat to different crops and a risk to food security. Currently, in maize, the pest is predominantly controlled by pesticides or transgenic events. However, the use of biological control agents is considered the most sustainable and preferred method of control, providing high effectiveness. Among the various natural enemies reported for FAW, the egg parasitoid Telenomus remus has gained most interest, and has been mass released against FAW in the Americas for many years. In addition to FAW, other armyworms of the genus Spodoptera often cause high crop damage and may be controlled using T. remus. Among other important aspects, this paper presents a review on T. remus mass rearing techniques, estimated costs of mass production, and release strategies. Due to the recent invasion of FAW in Africa, Asia, and Australia T. remus provides good opportunities for the establishment of an augmentative biological control program, reinforcing sustainable production of major crops such as maize in affected countries.

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Incubation Temperature Influences the Duration of Egg Hatching and Early Development in the Boreal Digging Frog, Kaloula Borealis

Journal of Zoo Biology ◽

10.33687/zoobiol.003.01.2267 ◽

2020 ◽

Vol 3 (1) ◽

pp. ACCEPTED

Author(s):

Rho-Jeong Rae

Keyword(s):

Water Temperature ◽

Early Life ◽

Rainy Season ◽

Incubation Temperature ◽

Life Stages ◽

Early Life Stages ◽

Egg Hatching ◽

Significant Difference ◽

The Mean ◽

Hatching Rates

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.

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Integrative taxonomy and phylogeography of Telenomus remus (Scelionidae), with the first record of natural parasitism of Spodoptera spp. in Brazil

Scientific Reports ◽

10.1038/s41598-021-93510-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ana P. G. S. Wengrat ◽

Aloisio Coelho Junior ◽

Jose R. P. Parra ◽

Tamara A. Takahashi ◽

Luis A. Foerster ◽

...

Keyword(s):

Biological Control ◽

Mitochondrial Gene ◽

First Record ◽

Mass Rearing ◽

Classical Biological Control ◽

Egg Parasitoid ◽

Integrative Approach ◽

Agricultural Pests ◽

Telenomus Remus ◽

Natural Parasitism

AbstractThe egg parasitoid Telenomus remus (Hymenoptera: Scelionidae) has been investigated for classical and applied biological control of noctuid pests, especially Spodoptera (Lepidoptera: Noctuidae) species. Although T. remus was introduced into Brazil over three decades ago for classical biological control of S. frugiperda, this wasp has not been recorded as established in corn or soybean crops. We used an integrative approach to identify T. remus, combining a taxonomic key based on the male genitalia with DNA barcoding, using a cytochrome c oxidase subunit I mitochondrial gene fragment. This is the first report of natural parasitism of T. remus on S. frugiperda and S. cosmioides eggs at two locations in Brazil. We also confirmed that the T. remus lineage in Brazil derives from a strain in Venezuela (originally from Papua New Guinea and introduced into the Americas, Africa, and Asia). The occurrence of T. remus parasitizing S. frugiperda and S. cosmioides eggs in field conditions, not associated with inundative releases, suggests that the species has managed to establish itself in the field in Brazil. This opens possibilities for future biological control programs, since T. remus shows good potential for mass rearing and egg parasitism of important agricultural pests such as Spodoptera species.

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Factors influencing the occurrence of fall armyworm parasitoids in Zambia

Journal of Pest Science ◽

10.1007/s10340-020-01320-9 ◽

2020 ◽

Author(s):

Léna Durocher-Granger ◽

Tibonge Mfune ◽

Monde Musesha ◽

Alyssa Lowry ◽

Kathryn Reynolds ◽

...

Keyword(s):

Biological Control ◽

Natural Enemies ◽

Smallholder Farmers ◽

Insect Pest ◽

Fall Armyworm ◽

Parasitoid Species ◽

Maize Crop ◽

Parasitism Rates ◽

Control Programmes ◽

Interest In Research

AbstractInvasive alien species have environmental, economic and social impacts, disproportionally threatening livelihood and food security of smallholder farmers in low- and medium-income countries. Fall armyworm (FAW) (Spodoptera frugiperda), an invasive insect pest from the Americas, causes considerable losses on maize to smallholder farmers in Africa since 2016. The increased use of pesticides to control FAW in Africa raises concerns for health and environmental risks resulting in a growing interest in research on biological control options for smallholder farmers. In order to evaluate the occurrence of local natural enemies attacking FAW, we collected on a weekly basis FAW eggs and larvae during a maize crop cycle in the rainy season of 2018–2019 at four locations in the Lusaka and Central provinces in Zambia. A total of 4373 larvae and 162 egg masses were collected. For each location and date of collection, crop stage, the number of plants checked and amount of damage were recorded to analyse which factors best explain the occurrence of the natural enemy species on maize. Overall parasitism rates from local natural enemies at each location varied between 8.45% and 33.11%. We identified 12 different egg-larval, larval and larval-pupal parasitoid species. Location, maize growth stage, pest density and larval stage significantly affected parasitoid species occurrence. Our findings indicate that there is potential for increasing local populations of natural enemies of FAW through conservation biological control programmes and develop safe and practical control methods for smallholder farmers.

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