scholarly journals Selectivity of registered pesticides for the corn crop on immature stages of Trichogramma pretiosum (Hymenoptera: Trichogrammatidae)

2019 ◽  
Vol 43 ◽  
Author(s):  
Tatiele Pereira dos Santos ◽  
Claubert Wagner Guimarães de Menezes ◽  
Carlos Henrique Batista ◽  
Eliane Souza Gomes Brito ◽  
Wagner de Souza Tavares ◽  
...  
Keyword(s):  
Biocontrol Agent ◽  
Zea Mays L ◽  
Positive Control ◽  
Egg Parasitoid ◽  
Negative Control ◽  
Trichogramma Pretiosum ◽  
Anagasta Kuehniella ◽  
Lepidoptera Pyralidae ◽  
Low Toxicity ◽  
Chemical Products

ABSTRACT Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae) is an egg parasitoid of lepidopteran pests in corn, Zea mays L. (Poaceae), in Brazil. Chemical products used in agriculture can be toxic to this biocontrol agent. The objective of the present study was to evaluate the longevity, parasitism and emergence of T. pretiosum parasitizing Mediterranean flour moth, Anagasta kuehniella Zeller, 1879 (Lepidoptera: Pyralidae), eggs treated with herbicide solutions with the active ingredients (chemical group) atrazine (triazines), paraquat dichloride (bipyridylium) and nicosulfuron (sulfonylurea). Pure distilled water was used as a negative control, and a solution of a product with λ-cyhalothrin + thiamethoxam (pyrethroid + neonicotinoid, respectively) was used as the positive control. The experimental design was completely randomized, with five treatments and 10 replicates. Anagasta kuehniella eggs were stored for two periods after treatment, 24 and 48 hours. These eggs were subjected to parasitism for two subjecting periods, 24 and 48 hours. The results were analysed statistically and classified according to the International Organization for Biological Control (IOBC). Atrazine and nicosulfuron reduced the longevity of T. pretiosum females. Nicosulfuron and the combination λ-cyhalothrin + thiamethoxam reduced the parasitism and emergence of this natural enemy. The paraquat dichloride-based herbicide was the least toxic and therefore represents a potential option for controlling weeds with low toxicity to the T. pretiosum parasitoid.

Efeito de Óleos Essenciais Sobre Estágios Imaturos de Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae)

2017 ◽  
Vol 21 (2) ◽  
pp. 80
Author(s):  
Douglas Silva Parreira ◽  
Francisco Andreas Rodrigues Dimaté ◽  
Lorena Duarte Batista ◽  
Humberto Corrêa Bomfim Ribeiro ◽  
Rafael Eugênio Guanabens ◽  
...  
Keyword(s):  
Allium Sativum ◽  
Positive Control ◽  
Egg Parasitoid ◽  
Negative Control ◽  
Mentha Piperita ◽  
Trichogramma Pretiosum ◽  
Insecticidal Effect ◽  
Lambda Cyhalothrin ◽  
Class 1 ◽  
Glass Tubes

O manejo integrado de pragas prioriza o uso de táticas de controle, que reduzam o impacto ambiental causado pelo uso maciço e incorreto de produtos químicos sintéticos. A preservação e liberação de inimigos naturais, nos campos agrícolas, e a descoberta de novas moléculas com efeito inseticida extraídas de espécies vegetais têm obtido bons resultados no controle de pragas. Porém, o efeito do uso conjunto dessas táticas de controle é pouco explorado. O objetivo desse trabalho foi avaliar o efeito de óleos botânicos sobre os estágios imaturos de Trichogramma pretiosum em laboratório. Ovos de A. kuehniella colados em cartelas de papel foram expostos a fêmeas, previamente individualizadas, em tubos de vidro durante 24h. Decorrido esse período, os ovos supostamente parasitados foram mergulhados em soluções de óleo essenciais (Allium sativum, Mentha piperita e Syzygium aromarticum), inseticida lambda-cialotrina (testemunha positiva) e etanol (testemunha negativa) durante 5 segundos, secos à sombra por trinta minutos e colocados em tubos de vidro. Os tubos foram mantidos em câmara climatizada a 25 ± 2°C, 70 ± 10% de UR e fotoperíodo de 12 h. Os óleos essenciais de A. sativum, M. piperita and S. aromarticum e o inseticida lambda-cialotrina foram levemente tóxicos (classe 2) a pupas de T. pretiosum. A razão sexual não foi afeta por nenhum composto classificando-os como inócuo (classe 1). Os óleos e o inseticida testado podem ser utilizados em associação com T. pretiosum, desde que os protocolos de seletividade ecológica sejam respeitados.Palavras-chave: Produtos naturais, parasitóide de ovos, seletividade.AbstractIntegrated pest management prioritizes the use of control tactics that reduce the environmental impact caused by the massive and incorrect use of synthetic chemicals. The preservation and release of natural enemies in agricultural fields and the discovery of new molecules with insecticidal effect extracted from plant species, have obtained good results in pest control. However, the effect to the use in joint of these control tactics is little explored. The objective of this work was to evaluate the effect of botanical oils on the immature stages of Trichogramma pretiosum in the laboratory. Eggs of Anticarsia kuehniella glued on paper plates were exposed to previously individualized females in glass tubes for 24 hours. After this period, the supposedly parasitized eggs were immersed in essential oil solutions (Allium sativum, Mentha piperita and Syzygium aromarticum), lambda-cyhalothrin insecticide (positive control) and ethanol (negative control) for 5 seconds, dried in the shade for 30 minutes and placed in glass tubes. The tubes were kept in an air-conditioned chamber at 25 ± 2°C, 70 ± 10% HR and 12-h photoperiod. The essential oils of A. sativum, M. piperita and S. aromarticum and lambda-cyhalothrin insecticide were slightly toxic (class 2) to T. pretiosum pupae. The sex ratio was not affected by any compound by classifying them as innocuous (class 1). The oils and insecticide tested can be used in association with T. pretiosum, since the ecological selectivity protocols are respected.Keywords: Natural products, egg parasitoid, selectivity.

scholarly journals Pengaruh Induksi Resistensi oleh Khamir Candida tropicalis terhadap Pertumbuhan Tanaman Cabai Terinfeksi Colletotrichum acutatum

Agrikultura ◽  
2019 ◽  
Vol 30 (1) ◽  
pp. 17
Author(s):  
Sri Hartati ◽  
Linda Tarina ◽  
Endah Yulia ◽  
Luciana Djaya
Keyword(s):  
Plant Height ◽  
Induced Resistance ◽  
Candida Tropicalis ◽  
Yield Loss ◽  
Biocontrol Agent ◽  
Dry Weight ◽  
Positive Control ◽  
Negative Control ◽  
Leaf Number ◽  
Colletotrichum Acutatum

ABSTRACTEffect of induced resistance by Candida tropicalis on the growth of chili plants infected by Colletotrichum acutatumColletotrichum acutatum is a major pathogen of chili that causes a big yield loss. Candida tropicalis has been reported as a biocontrol agent antagonistic to C. acutatum. The research was objected tofind out the effect of induced resistance by C. tropicalis on the growth of chili plants infected by C. acutatum. The application of the yeast was carried out by seed dipping and seedling spraying methods. As treatments, C. acutatum, the pathogen was inoculated at different time, i.e. A = inoculation at 3 days after the induction (dai) by C. tropicalis, B = inoculation at 7 dai, C = inoculation at 10 dai, D = positive control on inoculation at 3 dai, E = positive control on inoculation at 7 dai, F = positive control on inoculation at 10 dai, G = negative control with no induction nor inoculation. The results showed that the induction by C. tropicalis was able to increase the plant height, leaf number, and dry weight. The highest increase of plant height of 30.72% was caused by induction of C. tropicalis inoculated at 7 dai. Induction of C. tropicalis inoculated at 3 dai increased the leaf number by 49.47%, and the plant dry weight by 50%. C. tropicalis has a potency to be developed as plant growth inducer.Keywords: Antagonist, Inoculation, Fungi, YeastABSTRAKJamur Colletotrichum acutatum merupakan patogen penyebab kehilangan hasil panen yang cukup besar pada tanaman cabai. Salah satu mikrob antagonis jamur ini yang telah dilaporkan adalah khamir Candida tropicalis. Penelitian ini bertujuan untuk mengetahui pengaruh induksi resistensioleh C. tropicalis terhadap pertumbuhan tanaman cabai terinfeksi C. acutatum. Penelitian dilaksanakan dengan menggunakan teknik perendaman benih dan penyiraman bibit tanaman cabaimenggunakan suspensi C. tropicalis dengan waktu inokulasi patogen C. acutatum yang berbeda. Perlakuan tersebut adalah A = Inokulasi C. acutatum 3 hari setelah perlakuan induksi C. tropicalis (hsp), B = Inokulasi C. acutatum 7 hsp, C = Inokulasi C. acutatum 10 hsp, D = Kontrol (+) dengan inokulasi C. acutatum 3 hsp, E = Kontrol (+) dengan inokulasi C. acutatum 7 hsp, F = Kontrol (+) dengan inokulasi C. acutatum 10 hsp, G = Kontrol (-) tanpa induksi dan inokulasi. Hasil penelitianmenunjukkan bahwa perlakuan induksi resistensi oleh khamir C. tropicalis mampu meningkatkan tinggi, jumlah daun, dan bobot kering tanaman cabai. Kemampuan meningkatkan tinggi tanamancabai tertinggi terjadi pada perlakuan C. tropicalis dengan waktu inokulasi 7 hsp yaitu sebesar 30,72%. Perlakuan khamir C. tropicalis dengan inokulasi patogen 3 hsp mampu meningkatkan jumlah daun tanaman cabai sebesar 49,47%. Perlakuan C. tropicalis dengan waktu inokulasi 3 hsp mampu meningkatkan bobot kering tanaman sebesar 50%. Khamir C. tropicalis berpotensi untuk dikembangkan sebagai agens pemacu pertumbuhan tanaman.Kata Kunci: Antagonis, Inokulasi, Jamur, Patogen

scholarly journals Lethal, Sublethal And Transgenerational Effects of Insecticides Labeled For Cotton On Immature Trichogramma Pretiosum

2021 ◽  
Author(s):  
Mariana Abreu Costa ◽  
Elizeu Sá Farias ◽  
Eliana Donizete Andrade ◽  
Vinícius Castro Carvalho ◽  
Geraldo Andrade Carvalho
Keyword(s):  
Sex Ratio ◽  
Adult Emergence ◽  
Positive Control ◽  
Egg Parasitoid ◽  
Biological Traits ◽  
Trichogramma Pretiosum ◽  
Transgenerational Effects ◽  
Female Survival ◽  
Chemical Groups ◽  
Lepidopteran Pest

Abstract The egg parasitoid Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) regulates lepidopteran pest populations in cotton crops. However, cotton harbors dozens of pests, and growers rely on multiple insecticide applications to manage these damaging organisms. A harmonious integration of control tactics is required for proper pest management, and the use of selective insecticides (i.e., those promoting effective pest control while causing little impact on natural enemies) fits within this scope. This study aimed to assess the lethal, sublethal and transgenerational effects of insecticides from varying chemical groups on T. pretiosum. The insecticides were sprayed on parasitized host [Ephestia kuehniella (Zeller)] eggs with developing T. pretiosum stages (egg-larva, prepupa and pupa), and biological traits were assessed following adult emergence. Overall, pupae were more susceptible to the insecticides. We found thiodicarb and chlorfenapyr to reduce F0 adult emergence in rates comparable to the positive control (methomyl). Adult F0 deformation was the highest on flupyradifurone-treated organisms, and both the F0 parasitism rate and female survival were reduced by the insecticides (except for teflubenzuron). The sex ratio was affected by thiodicarb and flupyradifurone. Transgenerational effects occurred on adult emergence, which was reduced on the offspring (F1) of thiodicarb-, chlorfenapyr-, and flupyradifurone-treated T. pretiosum. In addition, thiodicarb lessened the F1 sex ratio. Combined, these results indicate that teflubenzuron is the safest insecticide; the other insecticides (especially thiodicarb and chlorfenapyr) are non-selective to T. pretiosum. Field and semifield studies are required to confirm the harmfulness of thiodicarb and chlorfenapyr towards T. pretiosum.

scholarly journals Temperature effects on Trichogramma pretiosum Riley and Trichogrammatoidea annulata De Santis

2003 ◽  
Vol 46 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Arlei Maceda ◽  
Celso L Hohmann ◽  
Honório R. dos Santos
Keyword(s):  
Temperature Effects ◽  
Entire Temperature Range ◽  
Temperature Threshold ◽  
Trichogramma Pretiosum ◽  
Degree Days ◽  
Parasitoid Species ◽  
Influence Of Temperature ◽  
Anagasta Kuehniella ◽  
Influence Of Temperature On ◽  
Lepidoptera Pyralidae

The influence of temperature on lifetime attributes of Trichogramma pretiosum Riley and Trichogrammatoidea annulata De Santis (Hymenoptera: Trichogrammatidae) was evaluated at four constant temperatures (15, 20, 25, and 30º C), RH 70 ± 10%, photophase 14 h. Anagasta kuehniella (Lepidoptera: Pyralidae) eggs were used as hosts. Developmental times of both parasitoid species were similar when exposed to 20, 25, or 30º C. T. annulata, however, developed slightly faster than T. pretiosum at 15º C. Emergence rates of both species were above 89%. The temperature threshold for T. pretiosum and T. annulata was 11º C and the number of degree-days required for their development was 126.9 and 122.3, respectively. Parasitization was maximal at 25º C. T. annulata, however, parasitized significantly more hosts than T. pretiosum in the entire temperature range. Temperature had no effect in brood size.T. annulata progeny consisted predominantly of males, except at 15º C, whereas in T.pretiosumitconsisted predominantly of females, except at 30º C. Parental females lived longer than males.

scholarly journals SELETIVIDADE DE PRODUTOS FITOSSANITÁRIOS UTILIZADOS NA CULTURA DA SOJA PARA PUPAS DE TRICHOGRAMMA PRETIOSUM RILEY, 1879 (HYMENOPTERA: TRICHOGRAMMATIDAE)

2010 ◽  
Vol 77 (2) ◽  
pp. 283-290 ◽  
Author(s):  
E.L. do Carmo ◽  
A.F. Bueno ◽  
R.C.O.F. Bueno ◽  
S.S. Vieira ◽  
M.M.P. Goulart ◽  
...  
Keyword(s):  
Trichogramma Pretiosum ◽  
Roundup Ready ◽  
Anagasta Kuehniella ◽  
Lepidoptera Pyralidae

RESUMO O objetivo do trabalho foi avaliar o efeito de produtos fitossanitários sobre pupas de Trichogramma pretiosum. Foram conduzidos três bioensaios em delineamento inteiramente casualizado com 11 tratamentos e cinco repetições. Em cada repetição, ovos de Anagasta kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae) foram utilizados como hospedeiro alternativo, sendo aderidos em cartelas de cartolina de 1 cm2 com solução de goma arábica à 40% e oferecidos para o parasitismo por 24h. Após 168-192h do parasitismo, quando os parasitoides estavam na fase de pupa, as cartelas foram mergulhadas por cinco segundos nos tratamentos testados. Avaliou-se a sobrevivência dos indivíduos tratados e a redução na emergência dos parasitoides foi classificada segundo as normas da IOBC. Os inseticidas flufenoxurom (Cascade®) 10, diflubenzurom (Dimilin®) 20 e metoxifenozide (Intrepid 240SC®) 21,6 e 36 g i.a. ha-1 foram classificados como inócuos. Permetrina (Valon 384 CE®) 49,92; betaciflutrina 12,5 + imidacloprido 100 (Connect®) e gama-cialotrina (Stallion 150SC®) 3,75 g i.a. ha-1 foram levemente nocivos. Clorpirifós (Lorban 480BR®) 384 e espinosade (Tracer®) 24 g i.a. ha-1 foram moderadamente nocivos. Os herbicidas glifosato 720 + imazetapir 90 (Alteza®); s-metolacloro (Dual Gold®) 1920; flumioxazina (Flumyzin 500®) 60; clomazona (Gamit®) 1000; glifosato 2880 (Gliz 480SL®); dicloreto de paraquate 600 + diurom 300 (Gramocil®); glifosato 1200 (Roundup Ready®); foram classificados como inócuos e os herbicidas 2,4-D (DMA 806BR®) 1209; dicloreto de paraquate (Gramoxone®) 600; glifosato (Roundup Transorb®) 2592 g i.a. ha-1 classificados como levemente nocivos. Os fungicidas tiofanato-metílico (Cercobin 500 SC®) 400; flutriafol 60 + tiofanato-metílico 300 (Celeiro®); carbendazin (Derosal 500SC®) 250; tebuconazole (Folicur EC®) 150; flutriafol (Impact®) 125; tebuconazole 120 + trifloxistrobina 60 (Nativo®); epoxiconazole 30 + piraclostrobina 79,8 (Opera®); epoxiconazole (Opus SC®) 12,5; azoxistrobina (Priori®) 50; azoxistrobina 60 + ciproconazole 24 (Priori Xtra®) g i.a. ha-1 foram classificados como inócuos aT. pretiosumna fase de desenvolvimento avaliada (pupa). Dentre os produtos avaliados, aqueles classificados como inócuos devem ser priorizados no manejo integrado de pragas (MIP) por compatibilizar o uso do controle químico sem prejudicar o controle biológico. Do mesmo modo, os produtos classificados como moderadamente nocivos devem ser evitados sempre que possível ou substituídos por outro de menor impacto.

scholarly journals Desempenho de Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae), submetido a inseticidas e fungicidas em dois hospedeiros

Revista CERES ◽  
2016 ◽  
Vol 63 (5) ◽  
pp. 653-660 ◽  
Author(s):  
Vinícius Pereira dos Santos ◽  
Dirceu Pratissoli ◽  
João Paulo Pereira Paes ◽  
Débora Ferreira Melo Fragoso ◽  
José Romário de Carvalho
Keyword(s):  
Helicoverpa Zea ◽  
Trichogramma Pretiosum ◽  
Anagasta Kuehniella ◽  
Lepidoptera Pyralidae ◽  
Lepidoptera Noctuidae

RESUMO Este trabalho teve como objetivo avaliar a influência de diferentes inseticidas e fungicidas, sobre Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae), em diferentes hospedeiros. Os testes foram realizados com adultos de T. pretiosum nos hospedeiros Anagasta kuehniella (Zeller, 1879) (Lepidoptera: Pyralidae) e Helicoverpa zea (Boddie, 1850) (Lepidoptera: Noctuidae). Os resultados mostraram que os agrotóxicos estudados tiveram efeitos diferentes sobre T. pretiosum, em função do hospedeiro. Os inseticidas IMIDACLORIPRIDO + BETA-CIFLUTRINA e METHOMYL foram os mais agressivos, reduzindo o parasitismo dos adultos de T. pretiosum em ambos os hospedeiros, enquanto, para os fungicidas, DIMETOMORPH + MANCOZEB e MANCOZEB foram os mais influentes. Diante dos resultados, conclui-se que o hospedeiro pode influenciar na ação seletiva dos inseticidas e fungicidas sobre parasitoides do gênero Trichogramma, visto que T. pretiosum foi mais susceptível ao inseticida METHOMYL e ao ACIBENZOLAR-S-METHYL, quando criado em A. kuehniella, e ao fungicida DIMETOMORPH + MANCOZEB, quando criado em H. zea. Não houve reduções expressivas dos percentuais de emergência dos descendentes, quando os fungicidas foram aplicados.

scholarly journals Influência do Fotoperíodo Sobre Aspectos Biológicos e Parasitismo de Ovos de Anagasta kuenhiella (Lepidoptera, Pyralidae) por Trichogramma pretiosum (Hymenoptera, Trichogrammatidae)

2012 ◽  
Vol 5 (2) ◽  
pp. 115-119 ◽  
Author(s):  
Marcelo Zart ◽  
Oderlei Bernardi ◽  
Adrise Medeiros Nunes ◽  
Fabiana da Silva Andersson ◽  
Silvana Manfredi-Coimbra ◽  
...  
Keyword(s):  
Sex Ratio ◽  
Controlled Environment ◽  
Alternative Host ◽  
Trichogramma Pretiosum ◽  
Cumulative Percentage ◽  
Daily Exposure ◽  
Anagasta Kuehniella ◽  
Lepidoptera Pyralidae ◽  
Biological Aspects ◽  
Old Females

Nesse trabalho estudou-se a influência do fotoperíodo e da densidade de ovos de Anagasta kuehniella (Zeller) sobre a biologia de Trichogramma pretiosum Riley. Diariamente foram expostas ao parasitismo cartelas contendo 40 ovos inviabilizados de A. kuehniella em ambiente controlado (25±1ºC, 70±10% UR) e com diferentes regimes de fotofase: escotofase (F:E): 0:24, 10:14, 12:12, 14:10 e 24:0 horas. Foram avaliados o número de parasitóides emergidos diariamente para determinação do percentual acumulado de parasitismo e a razão sexual. Com exceção da condição de fotoperíodo 24:0, houve uma redução linear na razão sexual das progênies ao longo dos dias de sobrevivência da fêmea, com 80% dos ovos parasitados até o oitavo dia de vida da fêmea. A partir do fotoperíodo mais adequado (12:12 horas) foi estudado o efeito da densidade de ovos do hospedeiro alternativo sobre o parasitismo por T. pretiosum através da exposição diária de 10, 20, 30 e 40 ovos de A. kuehniella ao parasitóide. Houve um aumento no número de ovos parasitados/dia/fêmea com as densidades crescentes de ovos expostos ao parasitismo. O parasitismo diário reduziu linearmente após a emergência da fêmea nas densidades de 20, 30 e 40 ovos/parasitóide, com exceção da densidade de 10 ovos em que o número de ovos parasitados/dia aumentou de forma quadrática até o sexto dia após a emergência da fêmea e depois reduziu. A melhor condição para criação de T. pretiosum é fotoperíodo 12:12 horas, com relação de 30 ovos de A. kueniella para cada fêmea do parasitóide. Influence of Photoperiod and the Density of Eggs Anagasta kuenhiella (Zeller) on Parasitism and Biological Aspects by Trichograma pretiosum Riley Abstract. In this work we studied the influence of photoperiod and density of Anagasta kuehniella (Zeller) on the biological aspects of Trichogramma pretiosum Riley. Cards containing 40 unviable eggs of A. kuehniella were daily exposed to parasitism in a controlled environment (25 ± 1 º C, 70 ± 10% RH) and in different photoperiod: scotophase (F: S): 0:24, 10:14, 12:12, 24:0 and 14:10 hours. We evaluated the number of emerged parasitoids for determining the cumulative percentage of parasitism and sex ratio. With the exception of 24:0 photoperiod condition, there was a linear decrease in sex ratio of progenies throughout the days of survival of the female, with 80% of eggs parasitized by 8-day old females. There was an increase in the number of parasitized eggs/day/female with increasing densities of eggs exposed to parasitism. The effect of eggs density of the alternative host on parasitism by T. pretiosum was studied in the 12:12 hour photoperiod, through daily exposure of 10, 20, 30 and 40 eggs of A. kuehniella to the parasitoid. Daily parasitism decreased linearly after the emergence of female densities of 20, 30 and 40 eggs/parasitoid, except the density of 10 eggs in which the number of eggs parasitized/day increased quadratically until the sixth day after the emergence of female, then reduced. The best condition for creation of T. pretiosum is 12:12 hours photoperiod, compared with 30 eggs of A. kueniella for each parasitoid female.

scholarly journals Biopesticidal Properties of Aqueous Crude Extracts of Tobacco (Nicotiana Tabacum L.) Against Fall Armyworm (Spodoptera Frugiperda J.E Smith) on Maize Foliage (Zea Mays L.) Diets

2020 ◽  
Vol 2 (1) ◽  
pp. p47
Author(s):  
Nyasha Sakadzo ◽  
Kasirai Makaza ◽  
Liberty Chikata
Keyword(s):  
Zea Mays ◽  
Nicotiana Tabacum ◽  
Spodoptera Frugiperda ◽  
Zea Mays L ◽  
Fall Armyworm ◽  
Positive Control ◽  
Negative Control ◽  
Distilled Water ◽  
Leaf Extracts ◽  
Nicotiana Tabacum L

Pesticidal plants offer valuable and sustainable options for managing Lepidopteran pests with considerable health, environmental and economic benefits in smallholder agro-ecosystem. This study Biopesticidal properties of aqueous crude extracts of tobacco (Nicotiana tabacum L.) against fall armyworm (Spodoptera frugiperda J.E Smith) on maize foliage (Zea mays L.) diets. Bio-efficacy of aqueous crude N. tabacum leaf extracts was evaluated under average room temperature at Great Zimbabwe University, Biology laboratory. The treatments were tobacco leaf extracts at four dosage levels (25 %, 33.33%, 41.67 % and 50% W/V ) and a negative control of untreated maize leaf foliage (distilled water) was used. A positive control of Carbaryl 85% WP was also used at label rates. The experiment was arranged in a Complete Randomized Design (CRD) replicated three times. Five larvae were placed into each of the experimental jars with maize foliage diets drenched into 10ml of distilled water in each treatment extract to keep the maize leaf foliage moist. Mortality for each treatment was recorded at 2 hourly intervals for 20 hours. Results showed that tobacco crude aqueous leaf extracts had Antifeedent activities against FAW larvae. The highest dose of 50% had significantly higher mean FAW larval mortalities (p< 0.05) than lower dosage (25%) and the negative control after 20 hours. However, 50% concentration was not significantly different (p>0.05) from the positive control and that of 33.33% and 41.67% dosages. The bioassay indicated that the 33.33% extract was superior in toxicity to 25% dose and the negative control but similar to higher extract doses though inferior to positive control. However, the mean mortality of 50% extract was not significantly different (p<0.05) from that of the positive control. This study recommends that 50% tobacco aqueous crude leaf extract dose to be used when controlling FAW in maize in the smallholder sector.

scholarly journals Biological characteristics of Trichogramma pretiosum and Trichogramma acacioi (Hym.: Trichogrammatidae), parasitoids of the avocado defoliator Nipteria panacea (Lep.: Geometridae), on eggs of Anagasta kuehniella (Lep.: Pyralidae)

2005 ◽  
Vol 48 (1) ◽  
pp. 7-13 ◽  
Author(s):  
Dirceu Pratissoli ◽  
José Cola Zanuncio ◽  
Ulysses Rodrigues Vianna ◽  
Josimar Souza Andrade ◽  
Luiz Carlos Marozzi Zanotti ◽  
...  
Keyword(s):  
Biological Control ◽  
Development Rate ◽  
Quadratic Model ◽  
Extreme Temperatures ◽  
Alternative Host ◽  
Trichogramma Pretiosum ◽  
Anagasta Kuehniella ◽  
Cubic Model ◽  
Lepidoptera Pyralidae ◽  
Number Of Individuals

The objective of this investigation was to study Trichogramma pretiosum and T. acacioi (Hymenoptera: Trichogrammatidae), parasitoids of the avocado defoliator Nipteria panacea (Lepidoptera: Geometridae) on the eggs of the alternative host Anagasta kuehniella (Lepidoptera: Pyralidae) aiming to use them for biological control of this pest in avocado orchards. The cubic model presented better adjustment for duration of the life cycle of T. pretiosum and T. acacioi with the host A. kuehniella which shows that development rate of these species increases with temperature within the range tested. The number of individuals of both Trichogramma species emerged per egg from this host was higher than one. The quadratic model was significant for viability of T. pretiosum and T. acacioi. This parameter was more affected by extreme temperatures and higher emergence rates of adults of both parasitoids species occurred at temperatures of 20, 25 and 30°C.

scholarly journals Selectivity of chlorantraniliprole and lambda-cyhalothrin to the egg parasitoid Telenomus podisi (Hymenoptera: Platygastridae)

2018 ◽  
Vol 39 (2) ◽  
pp. 549
Author(s):  
Gabriela Vieira Silva ◽  
Adeney De Freitas Bueno ◽  
Bruna Magda Favetti ◽  
Pedro Manuel Oliveira Janeiro Neves
Keyword(s):  
Positive Control ◽  
Egg Parasitoid ◽  
Negative Control ◽  
Stink Bug ◽  
Time Of Application ◽  
Lambda Cyhalothrin ◽  
Crop Development ◽  
Class 1 ◽  
Soybean Plants ◽  
Telenomus Podisi

Soybean plants host a diverse complex of pest insects, which can occur simultaneously during crop development. Thus, the use of egg parasitoids for the management of Euschistus heros (Fabricius) (Hemiptera: Pentatomidae) depends on the selectivity of the pesticides to the stink bug. Thus, the selectivity of the active ingredients chlorantraniliprole and chlorantraniliprole + lambda-cyhalothrin to the parasitoid Telenomus podisi (Ashmead) (Hymenoptera: Platygastridae) was evaluated. The bioassays were carried out under controlled conditions (27 ± 2 ºC and 50 ± 10% relative humidity) for the pupal and adult phases of the parasitoid. The design was completely randomized, with 10 treatments and five replicates composed of the insecticides chlorantraniliprole and chlorantraniliprole + lambda-cyhalothrin in different doses, as well as a negative control using water and a positive control using chlorpyrifos. We used a Potter Tower for the applications, and evaluations were carried out 24, 72, and 120 hours after the applications. Experimental methods and analyses to determine the harmfulness of the products to the insects were in accordance with International Organization for Biological Control standards. Chlorantraniliprole, at all doses tested, was less harmful to the parasitoid, especially in the adult phase; the doses were classified as class 1. The chlorantraniliprole + lambda-cyhalothrin mixture at its highest dose was classified as class 4, at 72 and 120 hours after application. For the pupal phase of the parasitoid, there were no significant differences, and the products were classified as class 1, except for the highest dose of chlorantraniliprole, which classified as class 2, at 24 hours after application. Thus, chlorantraniliprole can be considered a tool in the management of soybean pests. Its selectivity to T. podisi under the conditions tested presents low or no negative interference when sprayed on pupae and adults. However, the chlorantraniliprole + lambda-cyhalothrin mixture should be used with caution, respecting the time of application and the recommended doses, as it interferes negatively in the development of the parasitoid and should be replaced when possible.

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