Externally funded project

Entwicklung eines situationsbezogenen Konzeptes zur Regulation des Erbsenwicklers in Gemüse- und Körnererbsen (Erbsenwickler BLE)


Project Details
Project duration: 01/200612/2008


Abstract


We appraisedmating disruption (MD) to control peamoth, Cydia nigricana (Fabricius) (Lepidoptera:Tortricidae), by assessing male attraction to monitor traps, larval pod infestation, and larval agestructure in pheromone-treated and untreated grain pea fields [Pisum sativum L. (Fabaceae)], over a5-year period. Cellulose pheromone dispensers were manually attached to the top shoots of peaplants and released 540 mg ha1 day1 synthetic pheromone E8,E10-dodecadien-1-yl acetate in afirst test series (2000-2001) and ca. 4 200 mg pheromone ha1 day1 in a second series (2004-2006). The dispensers had a half-life of about 30 days. Although male attraction to pheromonemonitoring traps was largely suppressed at the edges and within MD fields in both test series, MDtreatments did not reduce pod infestation in the open field in 2000 and 2001. In the 2004-2006 series,larval damage reduction was achieved in themajority of the trials but overallMDefficacy in the openfield was only 61%and not significant. In contrast, in field cages placed within the experimental sitesand supplied with unmated pea moths,MD control was consistently high and significant. There wereno obvious differences in the larval age distribution in allMDand control treatments, suggesting thatinfestations started and developed further similarly. As a univoltine species, C. nigricana larvae stayin the soil of pea fields for hibernation and pupate. The following year, emerging adults disperse andfly to the closest pea crop. Combined emergence site and pea crop treatments were conducted over2 years to include this early migration phase of C. nigricana adults. However, the emergence sitetreatments did not enhance MD-control efficacy. We conclude that mating activity was only preventedin cage tests, whereas substantial mating occurred during the transit phase outside the pheromone-treated fields either within non-crop vegetation and/or at the edges of pheromone-treated peafields orientated upwind. Thus, resulting gravid female entry can be regarded as the major constraintto reliableMDcontrol.



Last updated on 2017-11-07 at 12:17