New Disease Reports

Figure 3 In October 2013, in a plantain farm in El Carmen canton in Manabí, Ecuador, the occurrence of wilted plants of cv. Barraganete with necrosis in vascular tissue of rhizomes and pseudostem was observed. Fruits were observed to ripen prematurely and exhibited an internal dry rot. Reddish necrotic spots were also noted in the rachis of the diseased bunches (Fig. 1). Symptoms resembled those described for Moko disease by Thwaites et al. (2000). Samples were taken to the Litoral Sur Experimental Station of INIAP for pathogen identification. A whitish ooze exuded from the vascular vessels of affected fruits when suspended in clean water. Pieces of infected tissue from rhizome and fruits were macerated in distilled water then plated onto triphenyl tetrazolium chloride (TZC) medium (Kelman, 1954). The resulting isolates of bacteria were tested for solubility in KOH, growth in King's B, nutrient agar (NA) and yeast extract-dextrose-calcium carbonate (YDC) media, and soft-rotting activity on potato slices. The resulting colonies were Gram negative according to their reaction with KOH, non-fluorescent in King's B, had cream colour in YDC and NA, had a reddish centre with white periphery on TZC (Fig. 2), and did not rot potato slices.