q-LAMP Assays for the Detection of Botryosphaeria dothidea Causing Chinese Hickory Canker in Trunk, Water, and Air Samples

Plant Dis. 2019 Dec;103(12):3142-3149. doi: 10.1094/PDIS-04-19-0773-RE. Epub 2019 Sep 25.

Abstract

Trunk canker disease caused by Botryosphaeria dothidea with a prolonged latent infection phase poses a serious threat to Chinese hickory production. To further understand the epidemiological characteristics and develop reasonable management techniques, a quantitative loop-mediated isothermal amplification (q-LAMP) assay was developed to quantitatively monitor B. dothidea in hickory plants, water, and air samples. Specific primers were designed based on the different sites of the β-tubulin sequence between B. dothidea and other fungi commonly found on Chinese hickory. At the optimum reaction temperature of 65.9°C, this loop-mediated isothermal amplification (LAMP) assay can specifically distinguish B. dothidea from other tested fungi. The limit of detection of LAMP assays for B. dothidea was 0.001 ng/µl of pure genomic DNA and 10 spores per 1 ml of water. The q-LAMP assay enables rapid detection of B. dothidea within 60 min in hickory trunk, water in hickory forests, and spores captured on tapes. These results provide a powerful and convenient tool for monitoring B. dothidea, which could be applied widely in epidemiology, forecast, and management of tree canker disease.

Keywords: pathogen detection; tree nuts.

MeSH terms

  • Air Microbiology
  • Ascomycota* / genetics
  • Carya* / microbiology
  • Microbiological Techniques* / methods
  • Nucleic Acid Amplification Techniques*
  • Water Microbiology