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The leaf roll disease in potatoes is caused by the leaf roll virus (PLRV, Potato leafroll virus , genus Polerovirus , family Luteoviridae ). It causes the upper leaves to curl, lighter foliage, and steeper growth.
As a result of the accumulation of assimilates in the sieve tubes , the removal of starch is inhibited due to the infestation in the vessels, the leaves become hard and brittle. Until the end of the 1980s , PLRV was the most important viral disease in potato cultivation . Infections take place exclusively via vectors ( persistent transmission ). The virus is removed from the sieve tube area by the aphids , reaches the digestive tract and is released again through the salivary glands . A suction process of at least two hours is necessary to infect a potato plant. Once infected, aphids are life-long vectors. The German range of varieties shows great differences in the susceptibility of the varieties, but most varieties are moderately susceptible to susceptible.
