Black Raspberries Have Resistance to Plant Insect

Till date breeding for aphid resistance has been recognized as an important tool for protecting red raspberries from viral infection.

But a new discovery has found that black raspberries have resistance to a disease-spreading aphid.

Aphids are also known as plant lice. Aphids can weaken a plant, stunt its growth, cause leaves to curl or wilt, and delay fruit or flower production.

Agricultural Research Service (ARS) horticulturist Chad Finn with the agency's Horticultural Crops Research Unit in Corvallis, Ore., and colleague Michael Dossett of Agriculture and Agri-Food Canada are the first to find and report black raspberry resistance to the large raspberry aphid.

For the study the researchers screened seedlings from 132 wild black raspberry populations fro aphid resistance.

A strong resistance was found in three of these populations one each from Ontario, Maine, and Michigan. They noticed that Aphid resistance in the Ontario and Maine populations seems to be controlled by multiple genes, while resistance in the Michigan population is governed by one dominant gene.

By identifying these genes it becomes easier for the breeders to incorporate aphid resistance into commercial black raspberry cultivators.

Aphid control is important because fruit production is severely impacted by black raspberry necrosis virus, which is transmitted by the large raspberry aphid. This and other aphids are important virus vectors in North American black raspberries.