Potato spindle tuber viroid (PSTVd) effects tomato, pepper and other solanaceous hosts. Symptoms include stunting, severe yellowing and distortion of the leaves. PSTVd is seed transmitted. 1000 seeds are tested for Potato spindle tuber viroid (PSTVd) by real time RT-PCR (TaqMan). However, this TaqMan assay also detects Tomato chlorotic dwarf viroid (TCDVd), and Tomato planta macho viroid (TPMVd). If the sample was positive, PCR and sequencing would be required to identify which viroid was present. There would be an additional charge for this testing.

Seed will be tested by a TaqMan assay that detects both Potato spindle tuber viroid (PSTVd) and the very closely related Tomato chlorotic dwarf viroid (TCDVd). If the sample was positive, and identification of the viroid was requested, PCR and sequencing would be required to identify if PSTVd or TCDVd was present. There would be an additional charge for this testing.