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Some of the most significant breakthroughs in the biological sciences this century will emerge from the development of next generation sequencing technologies. The ease of availability of DNA sequence made possible through these new technologies has given researchers opportunities to study organisms in a manner that was not possible with Sanger sequencing. Scientists will, therefore, need to embrace genomics, as well as develop and nurture the human capacity to sequence genomes and utilise the 'tsunami' of data that emerge from genome sequencing. In response to these challenges, we sequenced the genome of Fusarium circinatum, a fungal pathogen of pine that causes pitch canker, a disease of great concern to the South African forestry industry. The sequencing work was conducted in South Africa, making F. circinatum the first eukaryotic organism for which the complete genome has been sequenced locally. Here we report on the process that was followed to sequence, assemble and perform a preliminary characterisation of the genome. Furthermore, details of the computer annotation and manual curation of this genome are presented. The F. circinatum genome was found to be nearly 44 million bases in size, which is similar to that of four other Fusarium genomes that have been sequenced elsewhere. The genome contains just over 15 000 open reading frames, which is less than that of the related species, Fusarium oxysporum, but more than that for Fusarium verticillioides. Amongst the various putative gene clusters identified in F. circinatum, those encoding the secondary metabolites fumosin and fusarin appeared to harbour evidence of gene translocation. It is anticipated that similar comparisons of other loci will provide insights into the genetic basis for pathogenicity of the pitch canker pathogen. Perhaps more importantly, this project has engaged a relatively large group of scientists including students in a significant genome project that is certain to provide a platform for growth in this important area of research in the future.

Pitch canker, caused by the ascomycete fungus Fusarium circinatum, infects a wide range of Pinus species. The pathogen has a global distribution and limits plantation productivity wherever susceptible Pinus species are commercially cultivated. During 2005During -2007 symptoms typical of those associated with F. circinatum were observed in Colombia on nursery seedlings of P. maximinoi, P. tecunumanii and P. patula, as well as established P. patula and P. kesiya trees in plantations. Symptoms on seedlings included collar and root disease while shoot dieback and resinous stem cankers were found on trees in plantations.The aim of this study was to isolate and identify the causal agent of these symptoms and to evaluate the relative tolerance of various families of Pinus species commonly grown in Colombia. By making use of morphology and DNA-based methods, as well as pathogenicity tests on P. patula seedlings, it was possible to show that the symptoms observed in the nursery and field were caused by F. circinatum. Furthermore, the results of pathogenicity tests with two virulent isolates of the pathogen indicated that P. tecunumanii from lowelevation sources and P. maximinoi are significantly more tolerant to infection by F. circinatum than P. tecunumanii from high-elevation sources and P. patula. These results show that there is substantial opportunity to avoid losses due to infection by F. circinatum through deployment of resistant planting stock.2

Mango malformation, caused by Fusarium mangiferae, represents the most important floral disease of mango. The first symptoms of this disease were noticed in the beginning of 2005 in plantations at Sohar in the Sultanate of Oman. The affected inflorescences were abnormally enlarged and branched with heavy and dried-out panicles. Based on morphology and DNA-sequence data for the genes encoding translation elongation factor 1α and β-tubulin, the pathogen associated with these symptoms was identified as F. mangiferae.

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