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18. Grasshoppers and locusts

Author

Inglis, G. Douglas, Goettel, Mark S., Erlandson, Martin A., Weaver, David K., Lacey, Lawrence A., editor, and Kaya, Harry K., editor

Published
2007
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19. Using Stable Isotopes to Determine Natal Origin and Feeding Habits of the Army Cutworm Moth, Euxoa auxiliaris (Lepidoptera: Noctuidae).

Author

Dittemore, Clare M, Tyers, Daniel B, Weaver, David K, Nunlist, Erika A, Sowell, Bok F, Peterson, Erik, and Peterson, Robert K D

Subjects
STABLE isotopes, LEPIDOPTERA, NOCTUIDAE, MOTHS, GRIZZLY bear, SPRING, CANADIAN provinces
Abstract

The army cutworm, Euxoa auxiliaris (Grote), is a migratory noctuid that is both an agricultural pest and an important late-season food source for grizzly bears, Ursus arctos horribilis (Linnaeus, Carnivora: Ursidae), within the Greater Yellowstone Ecosystem. Beyond the confirmation of the moths' seasonal, elevational migration in the mid-1900s, little else has been documented about their migratory patterns. To address this missing ecological component, we examined (1) migratory routes during their spring and fall migratory periods throughout their natal range, the Great Plains, and (2) natal origin at two of their summering ranges using stable hydrogen (δ 2H) analyses of wings from samples collected within the areas of interest. Stable carbon (δ 13C) and stable nitrogen (δ 15N) analyses of wings were used to evaluate larval feeding habits of the migrants and agricultural intensity of natal origin sites, respectively. Results suggest that, rather than migrating exclusively east to west, army cutworm moths are also migrating north to south during their spring migration. Moths did not exhibit natal origin site fidelity when returning to the Great Plains. Migrants collected from the Absaroka Range had the highest probability of natal origin in Alberta, British Columbia, Saskatchewan, the most southern region of the Northwest Territories, and second highest probability of origin in Montana, Wyoming, and Idaho. Migrants collected in the Lewis Range had the highest probability of origin in the same provinces of Canada. Results suggest that migrants of the Absaroka Range fed exclusively on C3 plants as larvae and rarely fed in heavily fertilized agroecosystems. [ABSTRACT FROM AUTHOR]

Published
2023
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21. Grasshoppers and Locusts

Author

Inglis, G. Douglas, Goettel, Mark S., Erlandson, Martin A., Weaver, David K., Lacey, Lawrence A., editor, and Kaya, Harry K., editor

Published
2000
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22. Botanicals

Author

Weaver, David K., Subramanyam, Bhadriraju, Subramanyam, Bhadriraju, editor, and Hagstrum, David W., editor

Published
2000
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23. Dietary sugars and amino acids increase longevity and enhance reproductive parameters of Bracon cephi and B. lissogaster, two parasitoids that specialise on wheat stem sawfly.

Author

Cavallini, Laissa, Peterson, Robert K. D., and Weaver, David K.

Subjects
LONGEVITY, AMINO acids, SUGARS, SAWFLIES, DIETARY carbohydrates, FRUCTOSE, SUCROSE, WHEAT
Abstract

The wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), is a major pest of wheat grown on the Northern Great Plains and Canadian Prairies of North America, causing economic losses of as much as $350 million annually. Two species that parasitize wheat stem sawfly larvae in wheat stems are Bracon cephi (Gahan) and B. lissogaster Muesebeck (Hymenoptera: Braconidae). Carbohydrate‐rich diets increase adult parasitoid longevity and reproductive parameters, enhancing their success as natural enemies. In previous studies, these species had increased longevity, egg load, and volume when fed sucrose solutions, encouraging further research on their nutritional needs. Therefore, we conducted experiments with artificial diets using adult females fed sucrose, glucose, and fructose solutions. Females were also fed these sugars in combination with a mixture of amino acids. We assessed individuals daily for longevity. Both species benefited from diets containing carbohydrates, with an increase in longevity from an average of 9 to 51 days for B. cephi, and from 6 to 34 days for B. lissogaster. Additional experiments assessed egg load and volume after 2, 5, and 10 days of cumulative feeding in B. cephi. These females produced 1.4‐fold more eggs when fed amino acids, 2.5‐fold more with sugar, and 2.7‐fold more when fed sugar with amino acids. They had a 1.3‐fold increase in egg volume when fed amino acids, 1.9‐fold with sugar, and 2.1‐fold when fed sugar with amino acids. Our study reveals the nutritional requirements of these braconid parasitoids and the benefits of nutritional sources when implementing conservation biological control strategies. [ABSTRACT FROM AUTHOR]

Published
2023
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24. Using Stable Isotopes to Determine Natal Origin and Feeding Habits of the Army Cutworm Moth, Euxoa auxiliaris(Lepidoptera: Noctuidae)

Author

Dittemore, Clare M, Tyers, Daniel B, Weaver, David K, Nunlist, Erika A, Sowell, Bok F, Peterson, Erik, and Peterson, Robert K D

Abstract

The army cutworm, Euxoa auxiliaris(Grote), is a migratory noctuid that is both an agricultural pest and an important late-season food source for grizzly bears, Ursus arctos horribilis(Linnaeus, Carnivora: Ursidae), within the Greater Yellowstone Ecosystem. Beyond the confirmation of the moths’ seasonal, elevational migration in the mid-1900s, little else has been documented about their migratory patterns. To address this missing ecological component, we examined (1) migratory routes during their spring and fall migratory periods throughout their natal range, the Great Plains, and (2) natal origin at two of their summering ranges using stable hydrogen (δ2H) analyses of wings from samples collected within the areas of interest. Stable carbon (δ13C) and stable nitrogen (δ15N) analyses of wings were used to evaluate larval feeding habits of the migrants and agricultural intensity of natal origin sites, respectively. Results suggest that, rather than migrating exclusively east to west, army cutworm moths are also migrating north to south during their spring migration. Moths did not exhibit natal origin site fidelity when returning to the Great Plains. Migrants collected from the Absaroka Range had the highest probability of natal origin in Alberta, British Columbia, Saskatchewan, the most southern region of the Northwest Territories, and second highest probability of origin in Montana, Wyoming, and Idaho. Migrants collected in the Lewis Range had the highest probability of origin in the same provinces of Canada. Results suggest that migrants of the Absaroka Range fed exclusively on C3 plants as larvae and rarely fed in heavily fertilized agroecosystems.

Published
2023
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28. Evaluation of wheat stem sawfly‐resistant solid stem Qss.msub‐3BLalleles in hard red winter wheat

Author

Wong, Mei Ling, Bruckner, Philip L., Berg, Jim E., Lamb, Peggy F., Hofland, Megan L., Caron, Christopher G., Heo, Hwa‐Young, Blake, Nancy K., Weaver, David K., and Cook, Jason P.

Abstract

Host plant resistance provided by solid stems has been the most effective means for mitigating wheat stem sawfly (WSS) (Cephus cinctusNorton) damage in spring and winter wheat (Triticum aestivumL.). The solid stem trait originates from the spring wheat cultivar “Rescue” and is associated with a quantitative trait locus allele Qss.msub‐3BL.bthat explains the majority of the variation for stem solidness. Recently, a new Qss.msub‐3BLsolid stem allele, designated Qss.msub‐3BL.c, was identified in the spring wheat cultivar “Conan”. It produces a solid stem phenotype early in plant development but dissipates during plant growth. The Qss.msub‐3BL.callele provides effective WSS resistance in spring wheat but has not been tested in winter wheat. To examine if the Qss.msub‐3BL.callele provides adequate WSS resistance in winter wheat, near‐isogenic lines (NILs) were developed using marker‐assisted backcrossing. This enabled comparisons between the hollow stem Qss.msub‐3BL.a, solid stem Qss.msub‐3BL.band solid stem Qss.msub‐3BL.calleles for stem solidness, WSS resistance, and agronomic traits in Montana growing environments. Compared to the hollow stem allele, the NILs with the Qss.msub‐3BL.callele increased stem solidness and reduced WSS stem cutting. However, the Qss.msub‐3BL.callele resulted in lower solid stem scores and greater WSS stem cutting compared to the Qss.msub‐3BL.ballele. Overall, these findings indicate that the Qss.msub‐3BL.callele failed to provide sufficient WSS resistance in the winter wheat backgrounds tested in this study. Qss.msub‐3BLsolid stem alleles for wheat stem sawfly (WSS) resistance in hard red winter wheat are compared.Qss.msub‐3BL.bsolid stem allele provides better WSS resistance than the Qss.msub‐3BL.csolid stem allele.Winter wheat variety, Judee, has a unique temporal solid stem phenotype.

Published
2023
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