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Xylella fastidiosa Wells et al. causes disease in a number of plants in the southeastern United States, including southern highbush blueberry (Vaccinium corymbosum interspecific hybrids), but little was known concerning its potential impact in rabbiteye blueberry (Vaccinium virgatum Aiton syn. Vaccinium ashei Reade). In a naturally infected orchard in Louisiana, mean yields of X. fastidiosa–positive plants were 55% and 62% less than those of X. fastidiosa–negative plants in 2013 and 2014, respectively. Average berry weight was also lower in X. fastidiosa–positive plants. Within 3 years of testing positive for X. fastidiosa, four of nine X. fastidiosa–positive plants appeared dead. However, plants that were X. fastidiosa–negative in 2013 remained so until 2015, indicating that the bacterium did not spread rapidly in this established orchard during this time. Other factors, including soil chemistry variables, Phytophthora cinnamomi, ring nematode, and ringspot symptoms, were also investigated to determine if one of these might predispose plants to infection with X. fastidiosa or be partly responsible for observed yield loss. In most cases, interactions were not found, but associations with soil Cu and Zn suggest a need for further research on whether these elements predispose rabbiteye blueberry to X. fastidiosa infection and thereby contribute to yield losses. Researchers, extension workers, and growers should be aware of X. fastidiosa as a potential yield- and survival-impacting factor in rabbiteye blueberry.

Chinese windmill palms (Trachycarpus fortunei) exhibiting canopy decline symptoms suspected of being associated with a phytoplasma were observed in a residential landscape in Baton Rouge, Louisiana, USA. Internal stem tissue from diseased palms was tested for the presence of date palm lethal decline and lethal yellowing-related phytoplasmas. A 'Candidatus Phytoplasma palmae'-related subgroup 16SrIV-D phytoplasma was detected by restriction fragment length polymorphism analysis and confirmed by sequencing. The subgroup 16SrIV-D phytoplasmas have previously been reported on buccaneer palm, cabbage palm, Canary Island date palm, edible date palm, green thatch palm, pigmy date palm, queen palm, Rio Grande palmetto, and silver date palm. To the best of our knowledge, this is the first report of a 'Ca. P. palmae' -related subgroup 16SrIV-D phytoplasma on T. fortunei.

Lethal bronzing (LB), also previously known as date palm lethal decline or Texas Phoenix palm decline, associated with phytoplasma subgroup 16SrIV-D, was first identified in Louisiana in December 2013. A survey of palms showed that the disease was not only confined to City Park in New Orleans, where it was first detected, but is present in other parts of Orleans Parish, as well as two adjacent parishes. Canary Island date palms (Phoenix canariensis) tested positive at the highest frequency, and some edible date palms (P. dactylifera) and a small proportion of cabbage palms (Sabal palmetto) tested positive as well. Symptoms do not appear to be a reliable indicator of LB, because a substantial proportion of palms indicated as symptomatic tested negative. Furthermore, not all infected palms showed symptoms. Since the palm survey conducted in 2015 to 2016, LB has positively been identified from silver date palm (P. sylvestris) and Chinese windmill palm (Trachycarpus fortunei) in three additional parishes in Louisiana.

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