Broccoli Stunt, a New Disease in Broccoli Plants Associated with Three Distinct Phytoplasma Groups in Brazil

Since 2007, a new disease in broccoli (Brassica oleracea var. italica Plenck) has been observed in the São Paulo state, Brazil. The characteristic symptoms of the disease are plant stunting, inflorescence malformation, reddening of the leaves and phloem necrosis. Nested polymerase chain reaction with P1/Tint and F2n/R2 primer pairs revealed the presence of phytoplasmas in diseased broccoli plants. Restriction fragment length polymorphism and phylogenetic analysis of the 16S rDNA gene showed that phytoplasmas belonging to 16SrI, III and XIII groups were associated with the plants. To the best of our knowledge, this is the first report of phytoplasmas in this Brassica species in Brazil, as well the first time phytoplasmas of 16SrIII and XIII groups have been associated with broccoli plants.