FARMERS are being warned to continue aphid control even as the growing season draws to a close.
Department of Primary Industries Horsham lentil breeder Michael Materne said aphids had appeared in large numbers this season and it was important to protect lentils and chickpeas from the insects.
Dr Materne said aphids fed on lentils, colonised the plants and could multiply very quickly.
"In large numbers, the aphids can physically cause damage to lentil plants and potentially reduce grain yield," he said. "But the biggest concern with aphids is their ability to spread viruses which cause yield losses."
Dr Materne said this year detailed surveys of northwest Victorian chickpea crops had revealed high incidences of both cucumber mosaic virus, which was seed borne, and beet yellow mosaic virus which was spread by aphids.
"In less preferred crops such as chickpeas, aphids tend to move through the crop feeding and spreading viruses but do not remain in the crop."
Dr Materne said while the growing season was nearly over, aphid control remained an important consideration in lentil crops that were still flowering.
"This will prevent some viruses such as CMV and Alfalfa Mosaic Virus spreading to plants that may then produce virus-infected seed that affects next year's crop," Dr Materne said.
He said seed from paddocks that had virus symptoms should be tested for the virus before planting.
Dr Materne said the earlier aphids were controlled in lentils, the less chance there was of aphids multiplying and spreading viruses in lentils and other pulse crops.
