Author: Deana L. SexsonPublisher:
ISBN:
Category :
Languages : en
Pages : 196
Book Description
Colorado Potato Beetle Movement in Wisconsin Potato Cropping Systems
Author: Deana L. SexsonOff-crop Management of the Colorado Potato Beetle, Leptinotarsa Decemlineata (Say)
Author: Phillip E. KaufmanSome Insects Injurious to Truck Crops
Author: Charles Holcomb PopenoePublisher:
ISBN:
Category : Colorado potato beetle
Languages : en
Pages : 16
Book Description
Movement and Spatial Costs of Resistance in the Colorado Potato Beetle, Leptinotarsa Decemlineata (say), Coleoptera: Chrysomelidae
Author: Kathleen Schnaars UvinoPublisher:
ISBN: 9781303762789
Category :
Languages : en
Pages : 326
Book Description
The Colorado potato beetle, Leptinotarsa decemlineata is infamous for its' ability to develop resistance to insecticides and remains the most important insect defoliator of potatoes today. Long Island populations of the Colorado potato beetle have been at the forefront of developing resistance to every newly developed insecticide. Managing the evolution of resistance requires cultural as well as chemical means. Cultural efforts include field rotation, crop rotation, chemical rotation as well as refugia. Movement plays an integral part of both, the cultural schemes intended to thwart resistance evolution and the life history traits of the Colorado potato beetle. The use of refuges and crop rotation are often promoted to supplement the use of chemical pesticides in an effort to control crop pests. Refuges are untreated areas adjacent to treated crops, where susceptible genes can survive. The efficacy of refuges depends on movement between treated and untreated areas. Differences in movement between resistant and susceptible beetles can play a big role in the success of the refuge or rotation plan. Crop rotation can reduce the amount of insecticide used through dosage levels or frequency of application and slows insects' resistance evolution. Resistance to insecticides often has fitness costs associated with that resistance. I hypothesized that resistance to the insecticide Imidacloprid is correlated with reduced movement capability in Colorado potato beetles, Leptinotarsa decemlineata (Say) (henceforth potato beetles), the primary insect defoliator of potato plants. I examined whether migratory ability or flight propensity have a cost of resistance to imidacloprid in Colorado potato beetles, Leptinotarsa decemlineata (Say) by examining LD50's of flying emergers and walking emergers in the spring. Imidacloprid is the most widely used and in some cases the only effective insecticide for Colorado potato beetle control and there is currently a wide range of variation in resistance. In the spring overwintering potato beetle adults halt diapause and emerge from overwintering sites. For the purposes of this work I will use the definition of diapause presented by Tauber et al (1986): "a neurohormonally mediated, dynamic state of minimal activity that occurs during a genetically determined stage(s) of metamorphosis, usually in response to environmental stimuli that precede unfavorable conditions." Diapause in the Colorado potato beetle begins before the harsh conditions set in (loss of host and cold temperatures). It is an important strategy employed by many temperate zone insects for overwintering. Upon emergence from the overwintering site they emigrate to colonize local and distant fields. Emergence from diapause therefore offers an opportunity to sample genetically diverse groups of beetles. My results indicate that emerging flyers have a higher level of resistance than emerging walkers from overwintering sites. I also examined populations that were under intense selection pressure from one chemical, Spinosad, and largely isolated from other fields or populations. Spinosad is produced by a soil dwelling bacterium called Saccharopolyspora spinosa and it kills by ingestion. Spinosad is currently the only approved chemical available to Organic farmers on Long Island. These results indicate complete failure of Spinosad on that population but less resistance on distant populations and less resistance on populations from conventionally managed fields, all in Suffolk County, Long Island. Additionally early spring colonists of rotated and `non-rotated' fields were evaluated for resistance levels for 3 years. For two of the three years, colonists on long distance rotated fields had high LD50. Assuming long distance colonization is more likely dependent on flight, this is consistent with my results that emerging flyers have a higher LD50 than emerging walkers.
Colorado Potato Beetle Adaptation to Changing Agricultural Landscapes and Management Practices
Author: Michael Scott CrossleyPublisher:
ISBN:
Category :
Languages : en
Pages : 227
Book Description
Agricultural systems present a great opportunity, but also a number of great challenges, to herbivorous insects. Few insects that have ventured into agricultural systems have gained a foothold. One such insect, Colorado potato beetle (CPB; Leptinotarsa decemlineata Say), made its first appearance in a potato (Solanum tuberosum L.) field in 1859, and had risen to global superpest status by the 1990's. Critical to CPB's success was rapid adaptation to insecticides, but not all CPB populations have evolved resistance at the same rate. In the United States, CPB exhibits a striking regional pattern of decreasing insecticide resistance from East to West, and fine-scale spatial structure in resistance levels within some regions. In Chapter 1, I build on this knowledge by resurveying CPB resistance to a widely used class of insecticides, the neonicotinoids, in the Columbia Basin of northeastern Oregon and southeastern Washington, and find that susceptibility to neonicotinoids has persisted despite 20-40 generations of exposure. In Chapters 2 and 3, I use a landscape genetics framework to examine relationships between historic and contemporary land cover composition and population genetic differentiation, and find weak, correlated effects of contemporary potato and wheat land cover on genetic differentiation among CPB in the Columbia Basin, but no effect of land cover in the Central Sands of Wisconsin. In Chapter 4, I use a landscape genomics approach to identify genes putatively associated with insecticide resistance, and find evidence of adaptation from standing genetic variation at multiple genes. In Chapter 5, I combine literature review with new data analyses to evaluate the importance of key factors in maintaining susceptibility to insecticides among CPB populations in the northwestern US, and raise the hypothesis that maintenance of small population sizes, partly related to climate suitability, has been most influential. In Chapter 6, I curated historical US agricultural census data and used it to examine changes in amount, diversity, spatial pattern, and novelty of crop land cover in the conterminous US between 1840 and 2012. Results from this chapter provide a solid foundation for future studies of the causes and consequences of agricultural land cover change.
Colorado Potato Beetle
Author: Karen A. DelahautThe Colorado Potato Beetle in Mississippi
Author: Howard Evarts WeedPublisher:
ISBN:
Category : Colorado potato beetle
Languages : en
Pages : 22
Book Description
Potato Pests
Author: Charles Valentine RileyPublisher:
ISBN:
Category : Colorado potato beetle
Languages : en
Pages : 116
Book Description
The Colorado Beetle
Author: Charles Valentine RileyPublisher:
ISBN:
Category : Colorado potato beetle
Languages : en
Pages : 138
Book Description
Author: Scott Alan Chapman