Xanthomonas nasturtii

Xanthomonas nasturtii
Xanthomonas nasturii symptoms on watercress
Scientific classification Edit this classification
Domain: Bacteria
Phylum: Pseudomonadota
Class: Gammaproteobacteria
Order: Xanthomonadales
Family: Xanthomonadaceae
Genus: Xanthomonas
Species:
X. nasturtii
Binomial name
Xanthomonas nasturtii
Vincente, 2017

Xanthomonas nasturii a gram-negative, obligate aerobic bacterium that like many other Xanthomonas spp. bacteria has been found associated with plants, in particular watercress (Nasturtium officinale). It causes black rot of watercress.

Hosts and symptoms

Symptoms include small yellow or dark leaf lesions around the hydathodes, V -shaped leaf lesions, wilt, distortion of plants and early senescence. Initially the symptoms were attributed to Xanthomonas campestris due to the similarity of symptoms with black rot of brassicas.[1]

Distribution and economic importance

Watercress is a relatively small crop worldwide, but economically significant for some particular regions of the globe. Black rot of watercress can lower the quality of the watercress and possibly limit yields.[2][3] It was reported that infections can lead to up to 60% yield reduction and rejection of crops.[3]

The disease has been found in samples from the US, Florida[2] and Hawaii.[3] The disease has been regularly observed in Hawaii production in all islands, mostly during the rainy season from December to April in areas with poor air circulation.[4]

This disease has also been found in Europe, in Spain and Portugal.[5] It is likely that the disease can be seed transmitted as it has been detected in a seed sample from Spain.[5]

Control

Like for other bacterial diseases, control might involve the use of copper bactericides. It is advised to  minimize moisture on leaves by reducing overhead irrigation and increasing air circulation.[4]

References

  1. ^ Vicente, Joana G.; McHugh, John; Bryning, Adam; Carroll, Sarah; Harrison, James; Studholme, David J. (2023-08-01). "First Identification of Xanthomonas nasturtii as the Cause of Black Rot of Watercress in Hawaii". Plant Disease. 107 (8): 2511. doi:10.1094/PDIS-05-22-1043-PDN. ISSN 0191-2917. PMID 36867585. S2CID 257310931.
  2. ^ a b Vicente, Joana G.; Rothwell, Steve; Holub, Eric B.; Studholme, David J. (2017-09-01). "Pathogenic, phenotypic and molecular characterisation of Xanthomonas nasturtii sp. nov. and Xanthomonas floridensis sp. nov., new species of Xanthomonas associated with watercress production in Florida". International Journal of Systematic and Evolutionary Microbiology. 67 (9): 3645–3654. doi:10.1099/ijsem.0.002189. hdl:10871/29178. ISSN 1466-5026. PMID 28840805.
  3. ^ a b c Lascelles, Damien Mark (2019). Leaf edge senescence on watercress crops in southern Spain; cause and potential solutions:Industry Report (masters thesis). Lancaster University.
  4. ^ a b McHugh, J.J.; Constantinides, J.N. (2004). "Pest management strategic plan for watercress production in Hawaii. Workshop summary, University of Hawaii at Manoa, Honolulu, Hawaii, USA" (PDF).
  5. ^ a b Lascelles, D. M.; Roberts, M. R.; Cruz, L.; Cruz, J.; Studholme, D. J.; Harrison, J.; Greer, S. F.; Grant, M.; Holden, J. M.; Carter, B.; Bryning, A.; Carroll, S.; Aspin, A.; Vicente, J. G. (2022). "First report of black rot caused by Xanthomonas nasturtii on watercress in Spain and Portugal". New Disease Reports. 46 (2). doi:10.1002/ndr2.12134. ISSN 2044-0588.