Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

PCR based detection of latent infections of Botrytis aclada Fres. in onion bulbs.

Abstract

The ribosomal internal transcribed spacers (ITS1 and ITS2) were sequenced from isolates of Botrytis aclada [B. allii], the causal agent of onion neck rot, and isolates of the closely related species B. byssoidea and B. squamosa [Sclerotinia squamosa]. Alignment of the obtained ITS1 and ITS2 DNA sequences and published sequences from other closely related species showed very little variation between the species of Botrytis. Differences were only found at 4 positions in the ITS1 DNA region and none were found in the ITS2 DNA region. A B. aclada specific primer pair (ITS1ba and ITS2rev) was designed based on 1 base pair difference, giving a polymerase chain reaction amplification product of 280 base pairs. Using pure fungal cultures it was possible to exclusively amplify DNA from B. aclada.