Controlling aphids in vegetable crops
Warmer spring conditions encourage many species of aphids to accelerate their reproduction.
Several aphid species infest vegetable crops, differing in characteristics such as appendage and body colour, and wing vein size. Most are small, 1.5 to 3 mm in length, and bulbous in shape with thin legs. They can be winged or non-winged as adults. Winged species readily infest other host plants while non-winged aphids and nymphs are usually found in high numbers feeding on plants. Aphids can reproduce quickly. Some reproduce by telescoping generations with females carrying developing daughters who also carry their own developing daughters to be born live, not laid as eggs.
The sap feeding nature of aphids causes stunted plants, leaf curling and some discolouration. High numbers of aphids cause yield losses and their biggest impact on crops is how they spread viruses such as mosaic virus in lettuce and brassicas, and potato virus Y and potato leaf roll virus in potatoes.
One option to control aphids in lettuce and brassica crops is to treat seedling transplants in cell trays with Durivo®. Pirimor® 50 and Chess® WG are both registered for aphid control in potatoes, lettuces, and brassicas. Transform® is registered for aphids in several crops, including a number of vegetables, cereals and forage brassica crops. Potato-specific options include Benevia®, Mainman® or Movento® OD. Note that these three products also control tomato potato psyllid and work in integrated pest management programmes.
Predatory beneficial insects, such as hoverflies, ladybirds and brown lacewing, can help control aphids which they consume as a food source. Parasitic wasps also offer biological control by laying their eggs inside an aphid. The resulting larvae feed inside the aphid until they emerge as an adult, causing the parasitised aphids to take on mummified appearance.
For more information on controlling aphids in vegetable crops, speak to your local Fruitfed Supplies Technical Horticultural Representative.
ACVM registration numbers: Benevia® P008571, Chess® WG P005783, Durivo® P008003, Mainman® P008742, Movento® OD P008257, Pirimor® P001904. Read the registered label before use.