This page contains a Flash digital edition of a book.

Grower vigilance remains essential for SWD control

By Judie Steeves

there’s still much to find out about this new invasive pest of soft fruits that has spread across the continent and throughout Europe and England from its native Asia. Considerable research going on in


many different places, which will ultimately help growers to battle it. This year, the tiny vinegar fly

showed up earlier than in 2011 in local berry fields and it caused far more havoc. Tracy Hueppelscheuser,

entomologist with the provincial agriculture ministry in Abbotsford, says last year wild host monitoring showed no infestations until July 6, but this year the first pests appeared June 3. “So, we had an idea it would be a

tougher year,” she comments. Similar to 2010, it showed up in

blueberries and raspberries during late July and began to have an impact on fruit quality. Weather will determine over-

wintering mortality of the pest, but even if temperatures drop low enough to kill most of them some will survive to begin the cycle again in spring, she warns. SWD can survive 4 C and cooler for

 


Canadian Farm Business Management Council

 

 British Columbia Berry Grower • Winter 2012-13 13

lot has been learned about SpottedWing Drosophila during the past three years, but

an extended period of time, and at colder temperatures they are able to find warmer spots such as near buildings where they can overwinter. It’s not in the

commercial fields they overwinter, but in the wild spaces around fields, said Hueppelscheuser. As the weather

gets warmer they cycle faster. So, although females can live three to six months in cooler weather, in summer they live from a few days to a month but still lay 400 eggs in their lifetime. Growers must remember the

importance of good farm sanitation, in weeds and cull fruit. Bushes must be pruned so the

tractor can drive through and spray effectively in summer. Sprays must be applied in a timely

Entomologist Tracy Hueppelscheuser wasn’t surprised that this was a tougher year for Spotted Wing Drosophila.

manner, but fruit must also be harvested on time, to ensure there isn’t time for an infestation to take hold. “If fruit hangs for

too long it becomes a smorgasbord for SWD and the next crop of fruit is then also infested,” she warns. It’s vital that all

growers stay on top of it too, because the

weakest link can harm the whole industry, addsMark Sweeney, berry specialist with the agriculture ministry. In a long season, fruit must be

protected, from June through October. Susceptibility to SWD does vary

somewhat with varieties, but research is ongoing into that. Trapping will continue through winter to monitor populations.

Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16