Alternation of cowpea genotypes affects the biology of Callosobruchus maculatus (fabr.) (Coleoptera: Bruchidae)

Callosobruchus maculatus (Fabr.) is an important pest in stored cowpea, Vigna unguiculata (L.) Walp., with ample distribution in tropical and subtropical regions. The effect of alternation of cowpea genotypes, susceptible (S) and resistant (R), on the biology of (C. maculatus) was studied after four generations. A no-choice test was carried out in a completely randomized design, factorial scheme, with five treatments, four host combinations (RR, RS, SR and SS) and five replications. Each replication consisted of 30 grains of each genotype infested by two insect couples. The number of eggs per female was not different within or between combinations, evidencing that the genotypes and their alternation did not affect C. maculatus fecundity. Egg viability, however, varied between genotypes and between combinations. In combination RR, the longest duration of the immature stage was verified for genotype IT89KD-245; in addition, all genotypes presented the smallest survival for the same stage, resulting in a higher mortality of the pest. The resistance index categorized combination RR as moderately resistant for genotypes IT89KD-245, BR14-Mulato and BR17-Gurguéia, and as susceptible (S) only for IT89KD-260, demonstrating that these combinations were not very adequate for the development of C. maculatus, a fact that was confirmed by the better performance of the pest on the genotype from combination SS, and because of a reduction in its performance when it returned to resistant genotypes.

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Attractiveness, non-preference for feeding and oviposition to Ascia monuste orseis Godart (Lepidoptera: Pieridae) in collard greens

Arquivos do Instituto Biológico ◽

10.1590/1808-1657000362017 ◽

2018 ◽

Vol 85 (0) ◽

Author(s):

Luciano Nogueira ◽

André Cirilo de Sousa Almeida ◽

Marcelo Mueller de Freitas ◽

Zulene Antonio Ribeiro ◽

Arlindo Leal Boiça Junior ◽

...

Keyword(s):

Brassica Oleracea ◽

Free Choice ◽

Choice Test ◽

Breeding Programs ◽

Collard Greens ◽

Randomized Design ◽

Important Pest ◽

Completely Randomized Design ◽

Resistant Genotypes

ABSTRACT: Collard greens Brassica oleracea var. acephala is one of the most important horticultural grown in Brazil for human feeding. The caterpillar Ascia monuste orseis (Lepidoptera: Pieridae) stands out among the important pest in Brassicaceae causing severe plant defoliation. The objective of this study was to identify resistant genotypes (antixenosis) in 26 collard greens genotypes to A. monuste orseis. In free-choice test, randomized blocks were used; and in the non-choice test we adopted a completely randomized design. Manteiga de Jundiaí, crespa de Capão Bonito, couve de Arthur Nogueira 1, manteiga I-1811, manteiga de Ribeirão Pires I-1811, orelha-de-elefante and Pires 1 de Campinas presented antixenosis (non-preference for oviposition). Pires 1 de Campinas, manteiga I-1811, manteiga de São José, verde-escura and manteiga de Monte Alegre presented antixenosis (non-preference for feeding). These collard greens genotypes can be directly used by farmers for cultivation or by breeders as donor sources in breeding programs for resistance to A. monuste orseis.

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Resistência de genótipos de feijão-caupi [Vigna unguiculata (L.) Walp.] ao Ataque do Caruncho Callosobruchus maculatus (Fabr.) (Coleoptera: Chrysomelidae)

EntomoBrasilis ◽

10.12741/ebrasilis.v10i1.650 ◽

2017 ◽

Vol 10 (1) ◽

pp. 19-25

Author(s):

Westerllanya Rodrigues Medeiros ◽

Jayara Dayany da Costa Silva ◽

Paulo Roberto Ramalho Silva ◽

José Edmir Girão Filho ◽

Luiz Evaldo de Moura Padua ◽

...

Keyword(s):

Vigna Unguiculata ◽

First Generation ◽

Callosobruchus Maculatus ◽

Dry Weight ◽

Economic Losses ◽

Egg Viability ◽

Cowpea Weevil ◽

Phase Average ◽

Randomized Design ◽

Completely Randomized Design

Resumo. O caruncho Callosobruchus maculatus (Fabr.) é considerado a principal praga durante o armazenamento de grãos de feijão-caupi [Vigna unguiculata(L.) Walp.]. Devido aos prejuízos econômicos causados por este inseto, é de suma importância que se desenvolvam estudos que selecionem variedades resistentes a essa praga. Neste trabalho avaliou-se o efeito de genótipos de V. unguiculata sobre o comportamento e o desenvolvimento de C. maculatus em duas gerações consecutivas. O trabalho foi conduzido em Laboratório com condições de temperatura e umidade relativa monitoradas, em delineamento inteiramente casualizado utilizando os genótipos BRS Epace 10, Capela, BRS Urubuquara, BRS Pajeu, Itaim, BRS Rouxinol, Pingo de ouro, BRS Corujinha, IT85 F-2687 e BR 17 Gurguéia com oito repetições. Em cada genótipo foram confinados 10 adultos de C. maculatus para que fosse realizada a oviposição. Após um período de cinco dias, os adultos foram retirados dos potes contendo os genótipos. Aguardou-se a emergência dos adultos (primeira geração) e realizou-se nova infestação nos mesmos acessos para obtenção da segunda geração. Os parâmetros avaliados foram número de ovos total, viabilidade de ovos, número de adultos emergidos, viabilidade da fase imatura, período médio de desenvolvimento e peso seco dos adultos. O genótipo IT85 F2687 apresentou resistência do tipo não-preferência para oviposição e os genótipos BR 17 Gurguéia e BRS Urubuquara apresentaram resistência do tipo antibiose em relação à C. maculatus. O genótipo BR 17 Gurguéia foi o mais resistente dentre os genótipos estudados em relação à C. maculatus. Os genótipos Capela e Itaim foram caracterizados como suscetíveis a C. maculatus.Resistance of cowpea [Vigna unguiculata (L.) Walp.] genotypes to weevil attack Callosobruchus maculatus (Fabr.) (Coleoptera: Chrysomelidae)Abstract. The Cowpea weevil Callosobruchus maculatus (Fabr.) is considered the main Prague during storage of grains of Cowpea [Vigna unguiculata (L.) Walp.]. Due to the economic losses caused by this insect, is of paramount importance to develop studies to select varieties resistant to this pest. In this study assessed the effect of genotypes of V. unguiculata about the behavior and the development of C. maculatus in two consecutive generations. The study was conducted in laboratory with conditions of temperature and relative humidity monitored, in completely randomized design using BRS Epace 10, Capela, BRS Urubuquara, BRS Pajeu, Itaim, BRS Rouxinol, Pingo de ouro, BRS Corujinha, IT85 F-2687 and BR 17 Gurguéia genotypes with eight repetitions. In each genotype were confined 10 adults of c. maculatus for it was held the oviposition. After a period of five days, the adults were removed from the pots containing the genotypes. Waited-if the emergence of adults (first generation) and new infestation was held in the same access to obtain the second generation. The parameters evaluated were number of eggs, egg viability, total number of adults emergency, viability of immature phase, average period of development and dry weight of adults. IT85 F2687 genotype presented resistance of non-preference for oviposition and the genotypes BR 17 Gurguéia and BRS Urubuquara presented antibiose type resistance in relation to C. maculatus. BR 17 Gurguéia genotype was the strongest among the genotypes studied in relation to c. maculatus. The genotypes Capela and Itaim were characterized as susceptible to C. maculatus.</p

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Resistance to nematode Meloidogyne paranaensis in Arabica coffee genotypes introgressed with Coffea liberica

Australian Journal of Crop Science ◽

10.21475/ajcs.20.14.08.p2240 ◽

2020 ◽

pp. 1236-1241

Author(s):

Gustavo H. Sera ◽

Filipe G. Carvalho ◽

Inês C. de B. Fonseca ◽

Luciana H. Shigueoka ◽

Santino A. da Silva ◽

...

Keyword(s):

Germplasm Bank ◽

Breeding Programs ◽

Arabica Coffee ◽

Randomized Design ◽

Mother Plants ◽

Completely Randomized Design ◽

Set Up ◽

Moderately Resistant ◽

Reproduction Factor ◽

Coffea Liberica

The aim of this study was to prove that Arabica coffee introgressed with C. liberica, have resistance to Meloidogyne paranaensis (Mp). Open pollinated fruits were harvested from mother plants of 29 Arabica coffee genotypes from the IAPAR germplasm bank. Seeds were collected from the fruits and were sown to obtain seedlings to test the resistance to Mp. The experiment was set up in a completely randomized design with 29 coffee genotypes, 8 replications, and one plant per plot. Cultivars Catuaí Vermelho IAC 99 and IPR 100 were used as susceptible and resistant checks, respectively. Seedlings with three to four pairs of leaves were inoculated with 1,400 eggs and juveniles J2 of Mp (IP). At 120 days after inoculation, seedlings were evaluated by counting the nematodes per gram of roots, and the final nematodes population was obtained (FP). The reproduction factor (RF) was calculated using the formula: RF = FP/IP. The reproduction factor reduction was used to classify the resistance levels of genotypes, which were classified as highly resistant (HR), resistant (R), moderately resistant (MR), moderately susceptible (MS), susceptible (S) an highly susceptible (HS). All genotypes differed from Catuaí in resistance factor (RF), five of which did not differ from IPR 100 for RF, and only the line IAPAR 15242 had RF < 1.0. Out of 28 Arabica genotypes introgressed with C. liberica, five HR, 11 R, 11 MR and one MS were identified. However, only IAPAR 15242 and IPR 100 were classified as HR and presented 100% of HR plants, but only the first showed an RF < 1.0. Results revealed that these Arabica coffee genotypes with introgression of C. liberica genes have great potential to be used in breeding programs and they are a new alternative as a source of resistance.

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Rate of Release of Rhynchophorol Pheromone in Relation to Attraction of Rhynchophorus palmarum (L.) (Coleoptera: Dryophthoridae) in Oil Palm Plantations in Colombia

Journal of Entomological Science ◽

10.18474/0749-8004-55.4.487 ◽

2020 ◽

Vol 55 (4) ◽

pp. 487-498

Author(s):

Rosa Cecilia Aldana-De La Torre ◽

Luis Guillermo Montes-Bazurto ◽

Alex Enrique Bustillo-Pardey

Keyword(s):

Weight Loss ◽

Release Rate ◽

Oil Palm ◽

Release Rates ◽

Rhynchophorus Palmarum ◽

Randomized Design ◽

Baited Traps ◽

Important Pest ◽

Completely Randomized Design ◽

Pheromone Release Rates

Abstract Rhynchophorus palmarum (L.) (Coleoptera: Dryophthoridae) is an important pest in oil palm plantations, and its populations are monitored through rhynchophorol pheromone-baited traps. To optimize the release of rhynchophorol in high-density polyethylene diffusers, five calibers (2, 3, 4, 5, and 6) were evaluated. The experiment was conducted under a completely randomized design with 15 repetitions, recording daily weight loss of pheromones. Release rate of pheromone under laboratory conditions (30.2 ± 0.1°C; 70.8 ± 0.8% relative humidity [RH]) varied between 2.2 and 10.4 mg/day. Three diffusers with 2.4 ± 0.4, 3.6 ± 0.9, and 8.5 ± 1.3 mg/day of release rates, were selected for testing in three palm-growing zones. Adults of R. palmarum captured in traps with different diffusers were counted as well as pheromone weight loss. In two of three plantations, statistical differences were found in the capture of R. palmarum adults among the diffusers that presented different pheromone release rates (Eastern: F = 8.27; df = 2, 9; P = 0.0028; Central: F = 10.79; df = 2, 9; P = 0.0008; Southwestern F= 2.20; df = 2, 9; P= 0.1402). The diffuser with the release rate of 2.4 mg/day was selected because, after remaining 4 mo in the field, the traps with this diffuser registered catches statistically equal to those that had traps with newly installed diffusers. We concluded that the release rate of the pheromone of 2.4 mg/day is optimal for the capture of adults of R. palmarum during a period of 4 mo.

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IDENTIFICATION OF COWPEA GENOTYPES RESISTANT TO FUSARIUM WILT1

Revista Caatinga ◽

10.1590/1983-21252021v34n423rc ◽

2021 ◽

Vol 34 (4) ◽

pp. 957-964

Author(s):

RISONEIDE DE CÁSSIA ZEFERINO SILVA ◽

ANTHONY CARLOS DA SILVA ◽

REZANIO MARTINS CARVALHO ◽

ANTONIO FÉLIX DA COSTA ◽

ALESSANDRO NICOLI ◽

...

Keyword(s):

Fusarium Wilt ◽

Conidial Suspension ◽

The North ◽

Randomized Design ◽

Susceptible Control ◽

Bean Yield ◽

Descriptive Scale ◽

The University ◽

Moderately Resistant ◽

Resistant Genotypes

ABSTRACT Fusarium wilt, caused by soil-borne Fusarium oxysporum f. sp. tracheiphilum (Fot), can reduce cowpea bean yield. Considering that genetic control through resistant genotypes is pivotal for Fusarium wilt control, the aim of the present study was to identify cowpea genotypes that are resistant to Fot from the Germplasm Bank of the Pernambuco Agronomic Institute, Embrapa Middle North, and other producing areas in the North and Northeast regions of Brazil. The cultivar BR-17 Gurguéia was used as a susceptible control and MNC01-649F-2-1 was used as a resistant control. Two experiments were carried out in a completely randomized design in the greenhouse of the Department of Agronomy of the University Federal Rural of Pernambuco. Plants with the first pair of expanded leaves were inoculated with a conidial suspension (106 conidia/mL) using the conidia root-immersion methodology. Fusarium wilt severity in plants was assessed 21 d after inoculation, with the aid of a descriptive scale. In the first experiment, we evaluated the resistance of 38 cowpea genotypes, of which 19 (5 moderately resistant and 14 resistant) were selected for the second experiment. In the first experiment, four genotypes (Canapu PE, Miranda IPA 207, Esperança, and BRS Pujante) did not show any symptoms of Fusarium wilt. In the second, 15 genotypes showed high resistance to Fot, including Canapu PE and Miranda IPA 207, which again had no symptoms of Fusarium wilt. In conclusion, this study identified that the genotypes, Canapu PE, Miranda IPA 207, Esperança, and BRS Pujante have greater resistance to Fusarium wilt.

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Effect of Cowpea Seed Beetle (Callosobruchus maculatus) Infestation on Selected Landraces of Bambara Groundnut During Storage

Bioremediation Science and Technology Research ◽

10.54987/bstr.v9i2.624 ◽

2021 ◽

Vol 9 (2) ◽

pp. 31-34

Author(s):

Isma’ila Muhammad ◽

Nasiru Abdullahi ◽

Abdulmalik Bala Shu’aibu ◽

Ibrahim Musa ◽

Bawa Zakari Gambo ◽

...

Keyword(s):

Storage Time ◽

Callosobruchus Maculatus ◽

Bambara Groundnut ◽

State University ◽

Sources Of Resistance ◽

Improvement Program ◽

Randomized Design ◽

Percentage Weight ◽

Cowpea Seed ◽

Completely Randomized Design

The study was carried out to assess the effect of Callosobruchus maculatus infestation on selected Bambara groundnut (Vigna subterranean) landraces in Gombe during storage to determine the Landrace (s) that are less susceptible to infestation caused by C. maculatus during storage. The trial was done in the Botany laboratory of Gombe State University, Gombe. Seeds were collected from five different Landraces, 40 grams each of healthy and C. maculatus infestation free seeds were infested with two males and three females. Completely Randomized Design (CRD) with three replicates was used to assess the effects of C. maculatus infestation on the selected landraces of Bambara groundnut during storage. The results of the analysis of variance displayed significant differences (p≤ 0.05) among the parameters studied. It indicated that the Mottled and Cream landraces are relatively less susceptible and witness lower damage from the bruchids attack 14.6 (36%) and 17 (46%), whereas Red and Black landraces are more susceptible 24 (61 %) and 22 (57 %) (recorded higher damage from the C. maculatus in terms of percentage weight loss recorded). These results showed the existence of variation among the different Bambara groundnut landraces used due to the infestation of C. maculatus. It can be observed from this study that the use of infestation free landraces at storage time may perhaps be a worthwhile and auspicious factor for integrated pest management especially on bruchids in Bambara groundnuts. additionally, Mottle and Cream landraces might be employed as sources of resistance genes for the subsequent plant improvement program.

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Perubahan perilaku Callosobruchus maculatus Faaabricius terhadap warna cahaya pada kacang-kacangan di penyimpanan

Jurnal Agro ◽

10.15575/3735 ◽

2019 ◽

Vol 6 (1) ◽

pp. 15-23

Author(s):

Lukmanul Hakim ◽

Irhamni Irhamni

Keyword(s):

Callosobruchus Maculatus ◽

Oviposition Behavior ◽

Red Light ◽

Bean Seed ◽

Yellow Light ◽

Green Beans ◽

Randomized Design ◽

Completely Randomized Design ◽

Yellow Lights ◽

Copulation Behavior

Callosobruchus maculatus (Fab.) adalah salah satu species serangga dari ordo Coleoptera, family Brucidae yang merupakan hama kacang-kacangan di gudang penyimpanan. Kerusakan kacang selama penyimpanan diawali dengan perilaku oviposisi telur serangga betina dewasa pada kotiledon biji kacang. Serangga C. maculatus (Fab.) tidak menyukai tempat dengan cahaya terang. Penelitian ini bertujuan untuk mengamati perubahan perilaku oviposisi dan kopulasi serangga dewasa pada kacang-kacangan dengan penerangan empat warna cahaya pada ruang penyimpanan. Pengamatan dan analisis data menggunakan Rancangan Acak Lengkap Faktorial. Faktor petama menggunakan cahaya lampu merah, kuning, hijau dan putih, sedangkan faktor kedua terdiri dari tiga jenis kacang (Fabaceae) yaitu kacang hijau, kacang kedelai dan kacang merah. Hasil penelitian menunjukkan perilaku oviposisi telur terjadi pada cahaya lampu kuning, sedangkan perilaku kopulasi terjadi pada cahaya lampu merah. Cahaya lampu merah dan kuning dapat memengaruhi perilaku oviposisi dan kopulasi Callosobruchus maculatus (Fab.).ABSTRACTCallosobruchus maculatus (Fab.) is one of the insect species of the order Coleoptera, family Brucidae which is a pest for stored beans. Damage to beans during the storage starts with the behavior of the egg oviposition of adult female insects on bean seed cotyledons. C. maculatus (Fab.) do not like to be in a bright place. This study aimed to observe changes in the behavior of oviposition and copulation of adult insects in beans with four-colour lighting in the storage. The observation and analysis of data used factorial completely randomized design. The first factor were light colors; red, yellow, green, and white light while the second factor consists of three types of beans (Fabaceae); green beans, soybeans and red beans. The results showed that copulation behavior occurred in red light. While the oviposition behavior of eggs occured in yellow light. The red and yellow lights can affect the behavior of oviposistion and copulation of C.maculatus (Fab.).

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Evaluation of some Accessions of Bambara Groundnut (Vigna Subterranean L. Verdc) for Resistance to Bruchid Infestation, Based on Grain Source and Seed Coat Colour

Journal of Plant Protection Research ◽

10.2478/jppr-2013-0032 ◽

2013 ◽

Vol 53 (3) ◽

pp. 210-214 ◽

Cited By ~ 1

Author(s):

Bonaventure Chukwujindu Echezona ◽

Chinedu Felix Amuji ◽

Simon Eze

Keyword(s):

Seed Coat ◽

Callosobruchus Maculatus ◽

Adult Emergence ◽

Coat Colour ◽

Bambara Groundnut ◽

Oviposition Deterrence ◽

Seed Coat Colour ◽

Randomized Design ◽

Laboratory Trial ◽

Completely Randomized Design

Abstract The relative susceptibility of different accessions of Bambara groundnut (Vigna subterranean L. Verdc) to Callosobruchus maculatus (F.) was assessed in a laboratory trial in Nigeria. Treatments were comprised factorial combinations of four grain sources from Nigeria (Enugu, Anambra, Benue and Kogi state) and three predominantly contrasting seed coat colours (black, brown, and milky-colour) laid out in a completely randomized design (CRD). There were four replications of each treatment. Egg depositions by adult C. maculatus were affected by grain sources such that ovipositions on those sourced from the state of Anambra were significantly (p < 0.05) higher than those from other sources. Similarly, black coloured grains harboured more insects and eggs compared to other seed coat colours. Accesssions collected from Benue and/or those with a milky-coloured seed coat showed some levels of oviposition deterrence. However, the interaction of grain source and seed coat colour was not significant based on oviposition, adult emergence, and mortality counts. Grain sources and seed coat colour were, therefore, important traits to be considered while selecting ideotypes for resistance to C. maculatus

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Damage quantification and reaction of bean genotypes (Phaseolus vulgaris L.) to Meloidogyne incognita race 3 and M. javanica

Summa Phytopathologica ◽

10.1590/s0100-54052012000100004 ◽

2012 ◽

Vol 38 (1) ◽

pp. 24-29 ◽

Cited By ~ 7

Author(s):

Leonardo Nazário Silva dos Santos ◽

Fábio Ramos Alves ◽

Leônidas Leoni Belan ◽

Pablo Diego Silva Cabral ◽

Frederico de Pina Matta ◽

...

Keyword(s):

Root Nodules ◽

Root Weight ◽

Fresh Matter ◽

Damage Quantification ◽

Final Population ◽

Randomized Design ◽

Bean Plants ◽

Completely Randomized Design ◽

Moderately Resistant ◽

Dry Matter Weight

The damage and the resistance levels of cultivars and accessions of common beans rescued in the South and mountain regions of Espírito Santo State, Brazil, to M. incognita race 3 and M. javanica parasitism were evaluated under a greenhouse. Four rescued bean genotypes ("FORT-10", "FORT-13", "FORT-16" and "FORT-19") and 2 commercial cultivars: "Pérola", and "Aporé", were tested. The cultivar "Rico-23" was included as standard of susceptibility to nematodes and non-inoculated plants constituted the control. Thus, the experiment was carried out in a completely randomized design in 3 (treatments considering nematodes) x 7 (genotypes and bean cultivars) factorial arrangement, with 7 replicates. Data were measured at 50 days after plant inoculation. For damage quantification, the following variables were evaluated: plant height (PHE), number of nodes (NNO), number of trifoliate leaves (NRT), fresh matter weight (FWE) and dry matter weight (DWE) of shoots, root weight (RWE), number of root nodules (NRO) and final population (FPO) of nematodes per root system. There were no significant differences between the effects caused by M. incognita and M. javanica, but both species showed inferior values of PHE, NNO, NRT, RWE, FWE and DWE compared to controls. Concerning the levels of resistance of bean plants to M. incognita, the genotypes "FORT-10", "FORT-13", "Aporé" and "FORT-16" behaved as moderately resistant, the cultivars "Rico 23" and "Pérola" low resistant, and the genotype "FORT-19" as highly susceptible. When parasitized by M. javanica, the beans "FORT-19", "Rico-23", "FORT-16" and "FORT-13" were low resistant, "Pérola" and "Aporé" susceptible and "FORT-10" highly susceptible.

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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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