Symptoms of
bacterial leaf streak observed in barley, May 23, 2023
With crops emerging,
it’s time to scout for pests and diseases that can reduce yield. Don’t forget
to add bacterial leaf streak (caused by Xanthomonas translucens) to your
cereal diseases scouting list. Symptoms of this disease – such as water-soaking
lesions along the midrib of early leaves – have already been reported in barley
in southern Alberta in the county of Warner around May 23rd.
While there are no
in-season management options for control of bacterial leaf streak, monitoring
and recording the appearance, progress and impact of the disease will help you
learn by experience what might be expected in subsequent years.
Management
recommendations include:
- Use seed with little or no detectable bacterial
leaf streak risk - Rotate crops to provide at least a two-year
break between cereal crops - If possible, allow the canopy to dry thoroughly
between irrigation events
Prairie Crop Disease Monitoring Network, Quick Disease Reporter Tool Update map for bacterial leaf streak as of May 25, 2023. Map courtesy of Matthew McBurney, GIS Data Modeller, AAFC Winnipeg.
B Bacterial leaf streak symptoms on barley seedling leaves are quite distinct from those caused by the fungal leaf spot complex that includes scald, net- and spot-form net blotch, and spot blotch. Scald initially starts out as oval lesions that can have a water-soaked appearance. However, lesions then turn a grayish or turquoise colour, while mature scald lesions have an tan coloured interior with dark purple-brown borders and yellowing around the lesions. Net and spot blotch symptoms start off as small brownish lesions that may be oval in shape. As the infection progresses and the lesions mature, there can be yellowing around the brownish lesions. Net-form net blotch lesions can have a netted appearance with lesions being long and narrow, while symptoms of spot-form net blotch or spot blotch will be more oval to oblong in shape. Confirmation of scald and net-form net blotch is fairly straightforward as symptoms are quite diagnostic, while differentiating symptoms due to spot-form net blotch from spot blotch will require laboratory analyses.
ey leaf disease symptoms can be found at the following Prairie Crop Disease Monitoring Network (PCDMN) links:
More re information on typically barley leaf disease symptoms can be found at the following Prairie Crop Disease Monitoring Network (PCDMN) links: