First report of Cassava Bacterial Blight caused by Xanthomonas phaseoli pv. manihotis in the Amazonian forest of Ecuador

Xanthomonas phaseoli pv. manihotis (Xpm) is a plant pathogenic bacterium known as the causal agent of cassava bacterial blight (CBB). CBB is the most limiting bacterial disease affecting cassava (Manihot esculenta Crantz), characterized by diverse symptoms including angular water-soaked leaf lesions...

Ausführliche Beschreibung

Bibliographische Detailangaben
Veröffentlicht in:Plant disease. - 1997. - (2024) vom: 29. Feb.
1. Verfasser: Zárate-Chaves, Carlos A (VerfasserIn)
Weitere Verfasser: Moufid, Yassine, López, Camilo E, Bernal, Adriana J, Szurek, Boris, Yánez, Jeniffer Marcela
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2024
Zugriff auf das übergeordnete Werk:Plant disease
Schlagworte:Journal Article Causal Agent Crop Type Epidemiology Field crops Prokaryotes Subject Areas other
LEADER 01000naa a22002652 4500
001 NLM369123387
003 DE-627
005 20240301233111.0
007 cr uuu---uuuuu
008 240301s2024 xx |||||o 00| ||eng c
024 7 |a 10.1094/PDIS-10-23-2111-PDN  |2 doi 
028 5 2 |a pubmed24n1313.xml 
035 |a (DE-627)NLM369123387 
035 |a (NLM)38422440 
040 |a DE-627  |b ger  |c DE-627  |e rakwb 
041 |a eng 
100 1 |a Zárate-Chaves, Carlos A  |e verfasserin  |4 aut 
245 1 0 |a First report of Cassava Bacterial Blight caused by Xanthomonas phaseoli pv. manihotis in the Amazonian forest of Ecuador 
264 1 |c 2024 
336 |a Text  |b txt  |2 rdacontent 
337 |a ƒaComputermedien  |b c  |2 rdamedia 
338 |a ƒa Online-Ressource  |b cr  |2 rdacarrier 
500 |a Date Revised 29.02.2024 
500 |a published: Print-Electronic 
500 |a Citation Status Publisher 
520 |a Xanthomonas phaseoli pv. manihotis (Xpm) is a plant pathogenic bacterium known as the causal agent of cassava bacterial blight (CBB). CBB is the most limiting bacterial disease affecting cassava (Manihot esculenta Crantz), characterized by diverse symptoms including angular water-soaked leaf lesions, blight, wilting, stem exudates, stem cankers and dieback. CBB has been reported in most cassava-growing regions around the world, and, under conducive conditions, crop yield losses can reach up to 100% (Zárate-Chaves et al. 2021). While Xpm genetic diversity is remarkably high in South America (Bart et al. 2012) and cassava originates and was domesticated in the Amazon basin (Allem 2002), reports of CBB in the Amazonian region are missing. To fill this gap, in October 2018 we surveyed for CBB symptoms in cassava fields of the Orellana Province, located in the Amazon forest of the Republic of Ecuador. Adult cassava plants exhibiting typical angular, water-soaked leaf lesions were found in polyculture plots, i.e. intercrops of cassava with other species such as plantains and fruit trees (a.k.a. chakras). After surface disinfection with 5% sodium hypochlorite followed by 70% ethanol, white Xpm-like colonies were isolated from diseased leaf tissues of four plants on YPGA medium (yeast extract, 5 g/l; peptone, 5 g/l; glucose, 5 g/l; agar-agar, 15 g/l) supplemented with cephalexin (40 mg/l) and cycloheximide (50 mg/l). Pathogenicity tests were performed on peat-potted, 2-month-old cassava plants of the cultivar 60444. Bacterial suspensions were adjusted to an OD600 of 0.2 (2 × 108 CFU/ml) in sterile 10-mM MgCl2 and syringe infiltrated in fully-expanded leaves. In parallel, 20 µl of each bacterial suspension adjusted to an OD600 of 0.02 (2 × 107 CFU/ml) were inoculated on stems inside a hole previously punched with a sterile needle in the junction of the third-top petiole. Sterile 10-mM MgCl2 was used for mock inoculations in both leaves and stems, and experiments were replicated in three plants. Plants were incubated in a greenhouse at 28 ± 1°C with a 12-h photoperiod. Infiltrated leaves developed watersoaking 3 days post inoculation, while wilted leaves, stem exudates, and dieback were observed 21 days after stem inoculation. Control plants remained symptomless. White Xpm-like colonies were re-isolated from symptomatic leaves (Fig S1). One colony of each of the four Xpm isolates (before and after re-isolation) was assessed using diagnostic PCRs (Bernal-Galeano et al. 2018; Flores et al. 2019), using strain Xam668 as positive control. All four candidates were positive for both diagnostic tools. The sequences of the housekeeping genes atpD, dnaK, efp, glnA, gyrB and rpoD of our isolates were extracted from full genome sequences obtained through Oxford Nanopore Technologies (ONT) (GenBank OR288194 to OR288217) and compared to their homologs in four close Xanthomonas species and a reference Xpm strain (Table S1). The sequences of the tested strains aligned with that of Xpm CIO151 (GCA_004025275.1) (Arrieta-Ortiz et al. 2013) with nucleotide identity above 99.92% (Fig S2). The four strains were named CIX4169, CIX4170, CIX4171 and CIX4172, stored in the IRD Collection of Xanthomonas, where they are available upon request. To our knowledge, this is the first report of CBB in the Amazonian region and in Ecuador, where cassava is a central element for local culture and economy. Further surveys will be necessary to evaluate the distribution and prevalence of CBB in other ecozones of Ecuador where cassava is cultivated 
650 4 |a Journal Article 
650 4 |a Causal Agent 
650 4 |a Crop Type 
650 4 |a Epidemiology 
650 4 |a Field crops 
650 4 |a Prokaryotes 
650 4 |a Subject Areas 
650 4 |a other 
700 1 |a Moufid, Yassine  |e verfasserin  |4 aut 
700 1 |a López, Camilo E  |e verfasserin  |4 aut 
700 1 |a Bernal, Adriana J  |e verfasserin  |4 aut 
700 1 |a Szurek, Boris  |e verfasserin  |4 aut 
700 1 |a Yánez, Jeniffer Marcela  |e verfasserin  |4 aut 
773 0 8 |i Enthalten in  |t Plant disease  |d 1997  |g (2024) vom: 29. Feb.  |w (DE-627)NLM098181742  |x 0191-2917  |7 nnns 
773 1 8 |g year:2024  |g day:29  |g month:02 
856 4 0 |u http://dx.doi.org/10.1094/PDIS-10-23-2111-PDN  |3 Volltext 
912 |a GBV_USEFLAG_A 
912 |a SYSFLAG_A 
912 |a GBV_NLM 
912 |a GBV_ILN_350 
951 |a AR 
952 |j 2024  |b 29  |c 02