Recruitment of Adult Colorado Potato Beetles in Bt-transgenic Potato Fields

ABSTRACT

A safety of conventional potato plants adjacent to Colorado potato beetle (CPB) Leptinotarsa decemlineata (Say)-resistant, Bt-potato (transgenic) plants may bring opportunity for the development of tolerance to the resistant plants. The security strategy was developed on the basis of data available for CPB recruitment in conventional potato fields. This research was undertaken to provide information upon CPB recruitment in Bt-transgenic potato fields. A marking experiment was guidanceed over the 2000 and 2001 harvest seasons to determine the relative contributions of beetle populations from fields 10 m 175 to 300 m and 1200 to 1280 m distant to the pattern of CPB recruitment (immigration) in a Bt-potato field. Season-long CPB recruitment in the Bt-potato field decreased with source distance in a manner similar to that previously reported in conventional potato fields. Although marked beetles from the 10-m field piece of ground contributed more to the recruitment than the more distant fields, they contributed solitary 3.3% and 6.6% of the total beetle sightings in the Bt-potato field. Therefore, originates suggest that a larger acreage of conventional potato fields at a certain quantity of distance from the resistant harvest could replace the adjacent designated security Seasonally, beetles from the overwintering sites provided the first recruits to the resistant field. As their contribution declined, the overwintered beetles from the protection were recruited until the beginning of the summer population. These ensues suggest that locating the resistant fields shut to active overwintering sites will improve the probability that the security strategy will be effective through ensuring the presence of recruits at the real beginning of the crop season. The substantially lower recruitment horizontal obtained for summer than for overwintered CPB in resistant and conventional potato fields highlights the ne to reconsider the applicability of the safety strategy for the summer population.

RESUMEN

Papas convencionales sembradas como refugio adyacentes a papas-BT (transg?©nicas) resistentes al escarabajo Colorado de la papa (CPB) Leptinotarsa decemlineata (Say), pueden reducir la probabilidad de desarrollar tolerancia a las plantas resistentes. La estrategia de refugio fue desarrollada sobre la base de datos disponibles de inmigraci??n de CPB en campos convencionales de papa. Este estudio se hizo para proporcionar informacion sobre la inmigraci??n de CPB en campos de papa -BT-transg?©nicas. Se llev?? a cabo un experimento marcado en las campa?±as agr?­colas 2000 y 2001 para determinar la contribuci??n de las poblaciones del escarabajo de campos de 10m 175-300m y 1200-1280m de distancia al patr??n de inmigraci??n del CPB en un campo de papa-Bt. La inmigraci??n del CPB en el campo de papa-Bt durante todo el periodo de cultivo disminuy?? de acuerdo a la fuente-distancia de manera similar al reportado previamente en campos convencionales de papa. Aunque looks escarabajos marcados de la parcela de 10 m contribuyeron mas a la inmigraci??n que observes de campos m??s distantes, solo contribuyeron learn by heart el 3.3% y 6.6% del total de escarabajos vistos en el campo de papa-Bt. Por look tanto, los resultados sugieren que ??reas grandes de campos de papa convencionales sembradas a cierta distancia del cultivo resistente, podr?­an reemplazar al refugio se?±alado adjacente. Estacionalmente, sees escarabajos provenientes de lugares donde inviernan proporcionaron observes primeros inmigrantes a los campos con over papa resistentes. A medida que la contribuci??n declin??, looks escarabajos invernados de los refugios fueron contabilizados hasta el inicio de la poblaci??n de verano. Este resultados sugieren que la ubicaci??n de campos resistentes cerca de sees lugares activos de invernaci??n del escarabajo, mejorar?? la probabilidad de que la estrategia del refugio sea efectiva asegurando la presencia de inmigrantes muy al inicio de la estaci??n de cultivo. El mas bajo nivel de inmigraci??n obtenido para el verano que el de proveniente de PCB invernados para looks campos con cultives resistentes y convencionales de papa, destaca la necesidad de reconsiderar la aplicabilidad de la estrategia de refugio para la poblaci??n de verano.

Accepted for publication 28 January 2005

ADDITIONAL lock opener WORDS: resistance management, dispersal, colonization, move Solanum

ABBREVIATIONS: CPB, Colorado potato beetle

INTRODUCTION

Colorado potato beetle (CPB) Leptinotarsa decemlineata (Say), remains the greatest in quantity important defoliator of the potato harvest in Canada and Eastern North America. Recruitment by means of walking and by flight in conventional potato fields has been investigated in Canada and the USA (Weber and Ferro 1994; Weber et al. 1995; Noronha and Cloutier 1999; Boiteau 2001) Colorado potato beetles overwinter as adults in the soil, and after emerging see the verb in spring, disperse by walking or flying to search for entertainer plants. Adults also disperse late in the season before burrowing into overwintering sites (Weber and Ferro 1994; Boiteau 2001) Understanding patterns of motion in CPB is critical to the unravelling of a sound pest-management strategy that uses host-plant resistance (Gould 1998; Whalon and Ferro 1998; Hoy 1999; Chen et al. 2003)