A mutation was observed in N. tabacum L. cv. Dixie Shade, a cigar-wrapper variety. Mutant plants exhibit an extreme distortion of the lateral veins with a resulting puckering and rugose appearance, most apparent on the lower leaf surface. The leaves are usually narrower than normal, and are asymmetric in shape. Chlorotic areas may become apparent on mature leaves, and light colored streaks develop on the stalks. Considerable variability in degree of mutant expression can be seen in populations of mutant plants and the growth rate is slower than for normal cigar-wrapper varieties. This mutant has been termed roughoid (ro). Genetic evidence indicates roughoid is inherited as a two-factor recessive with variable expressivity. Mutant individuals should be of the genotype ro₁ ro₁ ro₂ ro₂. Functional diploidization for roughoid in the reported parental variety was not demonstrated.

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