Resisting the temptation: Using Transform to control Aphids in Canola

After the well documented Beet Western Yellows Virus (BWYV) outbreak in canola last year and prevalence of its key vector the Green Peach Aphid (GPA) (Myzus persicae) in both canola and cereals many growers will be looking for advice on their control options this year. Broad spectrum insecticides are usually a cost effective answer to pest control, unfortunately when it comes to GPA the resistance issues with organophosphates, synthetic pyrethroids and carbamates are widespread and there are too many cases of spray failure or poor control as a result of resistance to ignore. Anecdotal evidence from past seasons suggests that growers who have gone out early with a broad spectrum insecticides are faced with more pest problems later in the season. In particular issues with another highly insecticide resistant pest the diamondback moth which then in turn requires its own spray program to control. Whilst it is hard to predict the prevalence of any pest in a given season the presence of benefical insects can help to keep pest populations beneath the economic spray threshold and reduce the need for additional, costly control options.

Aphids alone can cause significant damage feeding on crops, depriving plants of nutrients and secreting honey dew which becomes covered in sooty mould, downgrading affected crops. When combined with viruses like Beet Western Yellows Virus and Barley Yellow Dwarf Virus which aphids spread through feeding, it is clear that using an insecticide with rapid knockdown is highly beneficial in reducing both feeding damage and the spread of viruses.

Canola crop infested with green peach aphids, June 2014.

Transform™ insecticide gives rapid knockdown, even in cool weather, of GPA as well as cabbage aphid, turnip aphid, oat aphid, corn aphid, grain aphid and rose grain aphid. Transform works both by contact at the time of application and also systemically providing residual control of feeding aphids for up to 2 weeks after an application. Its active ingredient, Isoclast™active, has not been implicated in any resistance testing. Feedback from last season suggests Transform was critical to many growers gaining control of GPA. Those who went straight to Transform quickly took care of pests and avoided the damage and expense of failed sprays.

Same crop a few hours later showing aphids on the ground and not on the crop.

The spread of aphid resistance means the importance of an effective IPM program for growers is increased. Transform is an excellent fit into IPM programs as it has minimal impact on beneficial insects and predatory mites. Unlike other products, Transform maintains beneficial insect populations which can aid in the control of pests throughout the season. In preference to older broad-spectrum insecticides Transform will help preserve lacewings, ladybeetles and aphid parasites in the crop. It can be aerially applied and has a short harvest WHP so it is ideal for use in that critical period of yield determination in the canola crop.

Business manager at Dow AgroSciences, John Gilmour cautions that whilst Transform is a fantastic product it should not be over used. “Transform can be applied twice to canola and cereal crops. Ideally, if a Group 4A product has been used as a seed treatment, e.g. Gaucho®, imidacloprid, etc., Transform should NOT be the next aphicide used.“ “This is crucial because we do not wish to overuse this very effective tool and promote the development of resistance in aphid populations. Avoid prophylactic sprays and harness Transform for use where it best fits, e.g. when pest pressure is high or when other modes of action (SP. OP or carbamate insecticides) simply do not work.”