Thermosensibilité des lignées germinales de Trichogramma brassicae Bezdenko (Hymenoptera). Conséquences sur l'efficacité du parasitoïde

1997 ◽  
Vol 75 (3) ◽  
pp. 484-489 ◽  
Author(s):  
J. Chihrane ◽  
G. Laugé
Keyword(s):  
Biological Control ◽  
Ostrinia Nubilalis ◽  
European Corn Borer ◽  
Ovarian Function ◽  
Thermal Conditions ◽  
Seminal Vesicles ◽  
Trichogramma Brassicae ◽  
Corn Borer ◽  
Large Numbers ◽  
Trichogramma Brassicae Bezdenko

Trichogramma brassicae, a parasitoid used in the biological control of the European corn borer, Ostrinia nubilalis, becomes less effective if certain thermal conditions prevail at the time of its release. A laboratory study demonstrated that the generation liberated in the field had reduced fecundity and that the proportion of females was lower in the following generation. These results prompted us to examine the germ lines of the parasitoid. Exposure to a temperature of 35 °C at the white nymph stage does not affect ovarian function, but exposure to 44 °C does: the number of mature ovocytes at emergence is lower than that observed in controls; certain ovaries are abnormal or remain juvenile. At the time of emergence, the seminal vesicles of male controls contain large numbers of typical sperm and a few atypical sperm, the latter becoming more numerous in males exposed to 35 °C. After exposure to 44 °C, vesicles contain only a few sperm or are completely empty. Since T. brassicae is an arrhenotokous parthenogenetic species (unfertilized eggs become males), these observations explain the reduced number of females in the second generation.[Journal translation]

scholarly journals Parasitoid inventarisation of European corn borer (Ostrinia nubilalis Hübner, 1796) and options for its biological control in Slovenia

2016 ◽  
Vol 107 (1) ◽  
pp. 93 ◽  
Author(s):  
Jaka RAZINGER ◽  
Špela MODIC ◽  
Annette HERZ ◽  
Gregor UREK
Keyword(s):  
Ostrinia Nubilalis ◽  
European Corn Borer ◽  
New Taxon ◽  
Agricultural Pests ◽  
Trichogramma Brassicae ◽  
Maize Production ◽  
Corn Borer ◽  
Promising Alternative ◽  
Hymenopteran Parasitoids ◽  
Chemical Pesticides

European corn borer (<em>Ostrinia nubilalis</em>)<em> </em>(ECB) is an important maize pest in central and northern Europe. Presently it is controlled by insecticides or biological agents such as <em>Trichogramma brassicae</em> in several European countries, excluding Slovenia, where the pest’s pressure is highly variable and no appropriate mechanization is available. Lessening the dependence on chemical pesticides is an integral part of the European Union’s agenda for agriculture. Mass release of <em>Trichogramma</em> spp. could be seen as a promising alternative for ECB control in countries with a highly fluctuating ECB pressure and no mechanization for insecticide applications. However, no records of naturally occurring hymenopteran parasitoids of ECB exist in Slovenia. To address this important under-researched topic and provide the expert basis for potential introduction of ECB egg parasitoids in Slovene maize production, a systematic inventarisation programme of ECB parasitoids was launched in 2010. Additionally, ECB flight was monitored in 2011 and 2012 at two locations in Slovenia: Jablje and Rakičan. In both locations two ECB generations  were observed. ECB was fist observed at the end of May in Rakičan. During the five years of the systematic survey we discovered two ECB parasitoid species. ECB egg masses were parasitized by <em>Trichogramma brassicae</em>, whereas ECB pupae were parasitized by <em>Tycherus nigridens</em>, with 6 or 7 % parasitation rate, respectively. <em>T. nigridens</em> represents a new taxon report for Slovenia. We conclude that there is a strong need for undertaking systematic surveys of natural enemies of agricultural pests.

scholarly journals Molecular identification of Trichogramma egg parasitoids of Ostrinia nubilalis in northeastern Serbia

2018 ◽  
Vol 70 (3) ◽  
pp. 425-432 ◽  
Author(s):  
Aleksandar Ivezic ◽  
Paul Rugman-Jones ◽  
Richard Stouthamer ◽  
Aleksandra Ignjatovic-Cupina
Keyword(s):  
Ostrinia Nubilalis ◽  
European Corn Borer ◽  
Preliminary Test ◽  
Egg Parasitoid ◽  
Egg Parasitoids ◽  
Coi Gene ◽  
Trichogramma Brassicae ◽  
Corn Borer ◽  
Trichogramma Species ◽  
Preliminary Identification

The European corn borer Ostrinia nubilalis (Hubner, 1796) (Lepidoptera: Pyralidae) is a major pest of corn (Zea mays Linnaeus, 1753) in Serbia. Regular monitoring of O. nubilalis in the region of Kikinda (province of Vojvodina, Serbia) demonstrated a high percentage of parasitized eggs of this pest. Preliminary identification of the egg parasitoids based on morphological traits revealed that they belong to the genus Trichogramma Westwood, 1833 (Hymenoptera, Trichogrammatidae). The objective of this study was to identify the autochthonous Trichogramma species present in the region of Kikinda by using sequences of ribosomal DNA. Specimens of Trichogramma were reared from parasitized eggs of O. nubilalis collected at different localities in the region of Kikinda. The ITS2 gene was sequenced and subjected to BLAST searches of GenBank NCBI (National Center for Biotechnology Information). The majority of collected specimens were identified as Trichogramma brassicae Bezdenko, 1968, and a single specimen as T. evanescens Westwood, 1833. Intraspecific variation of T. brassicae was assessed by amplifying the mitochondrial cytochrome oxidase I (COI) gene. Wasps were also tested for the presence of the endosymbiotic bacteria Wolbachia Hertig, 1936 using Wolbachia-specific 16S and wsp primers as a preliminary test for evidence of thelytoky. Understanding of the diversity and biology of autochthonous Trichogramma species is a key step in the potential commercial implementation of these egg parasitoid wasps in the protection of corn fields in Serbia.

INUNDATIVE RELEASE OF TRICHOGRAMMA BRASSICAE BEZDENKO (HYMENOPTERA: TRICHOGRAMMATIDAE) FOR CONTROL OF EUROPEAN CORN BORER IN SWEET CORN

1994 ◽  
Vol 126 (2) ◽  
pp. 291-301 ◽  
Author(s):  
Dicky S. Yu ◽  
J. Robert Byers
Keyword(s):  
European Corn Borer ◽  
Sweet Corn ◽  
Potential Method ◽  
Trap Catch ◽  
Trichogramma Brassicae ◽  
Corn Borer ◽  
Inundative Release ◽  
Southern Alberta ◽  
Experimental Plots ◽  
Trichogramma Brassicae Bezdenko

AbstractInundative release of Trichogramma brassicae Bezdenko for control of European corn borer was tested in experimental plots in 1991 and 1992 in southern Alberta, Canada, to determine its effectiveness as a potential method of control in sweet corn. The tests were conducted in 1-ha plots, in three different fields of irrigated sweet corn each year, at a release level of about 196 000 wasps per ha. The reduction in European corn borer damage in the release plots ranged from 85 to 87% in 1991 and from 45 to 95% in 1992. The reduction in damage was not significantly different in fields with 25 and 49 release points. General area degree-day accumulation for postdiapause development was not adequate to determine the timing of release for individual fields because European corn borer phenology varied among fields. Total moth catch in pheromone traps, however, was directly related to the number of plants damaged by European corn borer, and releases near the time of peak trap catch produced the greatest reduction in damage.

Predation by American crows reduces overwintering European corn borer populations in southwestern Ontario

1988 ◽  
Vol 66 (10) ◽  
pp. 2143-2145 ◽  
Author(s):  
Dan T. Quiring ◽  
Peter R. Timmins
Keyword(s):  
Biological Control ◽  
Zea Mays ◽  
Ostrinia Nubilalis ◽  
European Corn Borer ◽  
Biological Control Agents ◽  
Essex County ◽  
Corn Borer ◽  
Corvus Brachyrhynchos ◽  
American Crows ◽  
Ca 50

American crows (Corvus brachyrhynchos) overwintering in Canada's largest known crow roost near Essex, in southwestern Ontario, often forage during the day in surrounding fields of corn, Zea mays, where they perforate cornstalks and eat overwintering larvae of the European corn borer, Ostrinia nubilalis. Survival of overwintering larvae was ca. 50% less in uncaged than in caged plants in a field 26 km from the roost. Although crows perforated stalks in all fields < 25 km from the rookery that were sampled, the number of perforations per cornstalk was negatively correlated with the distance from the roost to the cornfields. In Essex county migratory crows do not arrive until October when most corn has been harvested and they leave in March, before corn is planted. Thus overwintering crows usually do not damage standing corn, increasing their importance as biological control agents.

Integration of Trichogramma ostriniae releases and habitat modification for suppression of European corn borer (Ostrinia nubilalis Hübner) in bell peppers

2009 ◽  
Vol 24 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Kathleen Russell ◽  
Ric Bessin
Keyword(s):  
Biological Control ◽  
Ostrinia Nubilalis ◽  
European Corn Borer ◽  
Block Design ◽  
Habitat Modification ◽  
Corn Borer ◽  
Promising Alternative ◽  
Randomized Block Design ◽  
Bell Peppers ◽  
Nectar Source

AbstractA two-year field study was conducted to evaluate the effectiveness of Trichogramma ostriniae Pang et Chen (T.o.) releases in combination with habitat modification, to enhance biological control of European corn borer (ECB), Ostrinia nubilalis Hübner, the key pest of bell peppers in Kentucky. A randomized block design with a split-plot treatment arrangement was used in both years. Buckwheat, Fagopyrum esculetum Moench, was inter-planted as a nectar source for the wasps and as an attractant for ECB natural enemies. Sentinel ECB egg masses were placed in each subplot to monitor establishment and dispersal of T. ostriniae within and between plots. Fruit were harvested at maturity, graded according to USDA standards, inspected for insect damage, and dissected to confirm ECB presence when evidence of entry was suspected, to determine percentage of infested fruits. Percent ECB infested fruit was reduced in plots with wasp releases and in plots with buckwheat inter-planted. The interaction of habitat modification and wasp releases significantly reduced pepper damage as a result of the synergy between tactics. Percentage of T. ostriniae parasitized sentinel eggs was significantly higher in wasp release plots compared to non-release plots. T. ostriniae releases used in conjunction with habitat modification for ECB control in bell peppers appears to be a promising alternative to traditional insecticide-based strategies for small-acreage and organic farms. This study displays an example system utilizing conservation biological control at a landscape level for pest suppression.

Dynamics of Nosema pyrausta in natural populations of the European corn borer, Ostrinia nubilalis: A six-year study

BioControl ◽  
2006 ◽  
Vol 51 (5) ◽  
pp. 627-642 ◽  
Author(s):  
Leslie C. Lewis ◽  
Douglas V. Sumerford ◽  
Lori A. Bing ◽  
Robert D. Gunnarson
Keyword(s):  
Ostrinia Nubilalis ◽  
European Corn Borer ◽  
Natural Populations ◽  
Corn Borer
Sign in / Sign up

Export Citation Format

Share Document