Cucurbit yellow vine bacterium occurs in Tennessee (US)
As reported in EPPO RS 98/111 and 98/192, a new disease of cucurbits called 'yellow vine' (EPPO Alert List) has been observed for the first time in 1988 in Oklahoma and Texas (US) on courgette and pumpkin (Cucurbita pepo). In 1991, it was also detected on melons (Cucumis melo) and watermelons (Citrullus lanatus). In severely affected fields, disease incidence can range from 50 to 100% with similar yield losses. The disease is thought to be caused by a phloem-limited bacterium but so far it has been impossible to isolate, culture and transmit the pathogen. PCR assays recently showed that the disease is constantly associated with a proteobacterium closely related to Serratia marcescens. Initially, the disease appeared limited to central and north-eastern Oklahoma and north-central Texas. In 1997-1998, it was observed in commercial fields of watermelons and melons from east Texas and in all cucurbit-growing areas of Oklahoma. In late summer 1998, symptoms were observed in one watermelon and three pumpkin fields in Tennessee. In these infected fields, disease incidence ranged from less than 1% to 20 %. PCR tests showed that the bacterium found in Tennessee on watermelon and pumpkin is the same as the one associated with yellow vine disease in Oklahoma and Texas. This new finding in Tennessee may suggest that this emerging disease may be more widespread than originally thought.
Bost, S.C.; Mitchell, F.L.; Melcher, U.; Pair, S.D.; Fletcher, J.; Wayadande, A.; Bruton, B.D. (1999) Yellow vine of watermelon and pumpkin in Tennessee.
Plant Disease, 83(6), p 587.