02376naa a2200217 a 450000100080000000500110000800800410001910000170006024500960007726000090017352016630018265000110184565000220185665000140187870000160189270000200190870000200192870000240194870000190197277301670199116560612010-01-27       2009    bl uuuu     u00u1 u    #d1 aWAALWIJK, C.  aDevelopment of a detection method for tropical race 4 of Fusarium oxysporum f. sp. cubense.  c2009  aFusarium oxysporum f. sp. cubense (Foc) is the causal agent of Fusarium wilt, the devastating disease that ruined the 'Gros Michel' (AAA)-based banana production in the early 1900s. The occurrence of a new variant, called tropical race 4 (TR4), in Southeast Asia that overcomes the resistance in Cavendish clones such as 'Grand Naine' (AAA) is a major concern to current banana production worldwide. The threat posed by this new variant could be overcome by the introduction of resistant cultivars. However, the identification of new resistant sources or breeding for resistance is a log-term effort. At the moment, the only option to control the disease is to eradicate infected plants and isolate infested plantations, to avoid or reduce the spread of the paathogen. This requires a sensitive and highly specific diagnostic that enables early detection of the pathogen and prevents false positives as this will have dramatic economic consequences for the banana growers. A two-locus database of DNA sequences, from over 800 different isolates from multiple formae speciales of F. oxysporum, was used to develop a molecular diagnostic tool that specifically detects isolates from the vegetative Compatibility Group (VCG) 01213, which encompasses the Foc TR4 genotypes. This diagnostic tool was able to detect all Foc TR4 isolates tested, while none of the Foc isolates from 19 VCGS other than 01213 showed any reaction. In addition, the developed diagnostic tool was able to detect Foc TR4 when using DNA samples from different tissues of 'Grand Naine' plants inoculated with TR4 isolates. Details on specificity, sensitivity and accuracy will be presented.  aBanana  aDoença de Planta  aFusariose1 aDITA, M. A.1 aBUDDENHAGEN, I.1 aPAIVA, L. V. K.1 aSOUZA JUNIOR, M. T.1 aKEMA, G. H. J.  tIn: ISHS/PROMUSA BANANA SYMPOSIUM, 2009, Guangzhou, China. Global perspectives on asian challenges: programme and abstracts. Guangzhou: ISHS: Promusa, 2009. p.38.