Leaf roll virus

Symptoms

- First year: None, or rolling of upper leaves, pale yellow, sometimes with purple discolouration. Rolling often more pronounced at the base of the primary leaflets. Rolling occasionally extending to lower leaves.

Second year: Rolling of lower leaves, usually from the tip of the primary leaflets, sometimes extending to upper foliage. Leaves dry and crisp, becoming brown at edges. The top of the plant may be paler and with leaves in more erect position giving a 'shuttlecock' effect. Generally no tuber symptoms.

Leaf rolling may also be caused by aphid feeding damage, blackleg, stem canker and mechanical injury to the stem base.