Woodpigeons Columba palumbus cause significant damage to oilseed rape
Brassica napus. (Cruciferae) in Britain, especially between January an
d March. The potential of cinnamamide, a non-lethal chemical repellent
, to protect growing oilseed rape from woodpigeon damage was assessed
in 20 x 20 m plots laid out in a 9-ha held frequented by >500 woodpige
ons. Despite a low initial loading of cinnamamide and low persistence
of the compound after spraying, the inner leaves of treated plants rec
eived less damage than the inner leaves of untreated plants (P < 0.05)
. This was reflected later in the trial in a decline in damage to the
outer leaves of treated plants (P < 0.05). No signs of phytotoxicity w
ere seen on treated leaves during the trial. Cinnamamide did not compl
etely protect the rape, and some plants in treated plots received cons
iderable damage. This was probably due to the compound's poor persiste
nce on the leaf and because it was applied late in the growing season
(late February) when birds had already made inroads into the crop. (C)
1998 SCI.