Black Sigatoka disease: new technologies to strengthen eradication strategies in Australia

Abstract

Abstract. In 2001, an incursion of Mycosphaerella fijiensis, the causal agent of black Sigatoka, was detected in Australia's largest commercial banana growing region, the Tully Banana Production Area in North Queensland. An intensive surveillance and eradication campaign was undertaken which resulted in the reinstatement of the disease-free status for black Sigatoka in 2005. This was the first time black Sigatoka had ever been eradicated from commercial plantations. The success of the eradication campaign was testament to good working relationships between scientists, growers, crop monitors, quarantine regulatory bodies and industry. A key contributing factor to the success was the deployment of a PCR-based molecular diagnostic assay, developed by the Cooperative Research Centre for Tropical Plant Protection (CRCTPP). This assay complemented morphological identification and allowed high throughput diagnosis of samples facilitating rapid decision-making during the eradication campaign. This paper describes the development and successful deployment of molecular diagnostics for black Sigatoka. Shortcomings in the gel-based assay are discussed and the advantages of highly specific real-time PCR assays, capable of differentiating between Mycosphaerella fijiensis, Mycosphaerella musicola and Mycosphaerella eumusae are outlined. Real-time assays may provide a powerful diagnostic tool for applications in surveillance, disease forecasting and resistance testing for Sigatoka leaf spot diseases.

From local to central: a network analysis of who manages plant pest and disease outbreaks across scales

“…Eradication activities were completed in May 2002, but monitoring continued over the next 12 months (Peterson 2002). No black sigatoka was detected after November 2001, and Australia was officially declared free of the pathogen in March 2005 (Henderson et al 2006). In total, the eradication cost of the Tully outbreak was AUD$17 million (Cook et al 2013).…”

“…Success was credited to effective partnerships (Henderson et al 2006). The response mobilized significant local action, with local industry and growers making substantial contributions to the cause of eradication.…”

“…The role of the state and national scales relates to designing and funding plans. In the case of black sigatoka, there was a great deal of conflict across scales, to the point that local stakeholders, i.e., industry and local state government, essentially rejected the state's eradication plan and instead implemented their own project with industry backing (Peterson 2002, Henderson et al 2006). …”

“…Although in more recent years record keeping with respect to incursions has improved dramatically, obtaining such information from Queensland state and Australian national governments was not possible for the 2001 event. Instead we compiled the response network using in-depth interviews with seven key stakeholders and published accounts (Peterson 2002, Henderson et al 2006. The unpublished account in particular provides details on the stakeholders involved at local scales.…”

“…Before 2001, black sigatoka had never been detected in or near a commercial bananagrowing region (Peterson 2002). In April 2001, black sigatoka was detected during a routine survey on a number of wild plants within the Tully Banana Production Area, the largest commercial banana-growing region in Australia (Peterson 2002, Henderson et al 2006, Cook et al 2013.…”