Gel: gel electrophoresis. LFD: lateral flow dipstick. +: Positive reaction.-: Negative reaction. Table 4 Strains of Citrus pathogenic Xanthomonas used to evaluate the CBC-LAMP assay Species Strain (s) Origin CBC type Detection Method Host Place Country Gel LFD S G Xanthomonas citri subsp. citri XC1CE Tangerine Concordia, Entre Rios Argentina A + + + BIBW2992 mouse XC2COE Orange Colon, Entre Rios Argentina A + + + XC3AM-1, XC3AM-2 Lemon Apostoles, Misiones Argentina A + + + XC4PM Grapefruit Posadas, Misiones Argentina A + + + XC5LF-1, XC5LF-2 Grapefruit
Las Lomitas Argentina A + + + XC7ETS-1, XC7ETS-2 Orange El Tabacal, Salta Argentina A + + + XC8SPB-1, XC8SPB-2 Orange San Pedro, Buenos Aires Argentina A + + + XC9CAT -1, XC9CAT-2 Orange Catamarca Argentina
A + + + XC10BVC -1, XC10BVC -2 Lemon Bella Vista, Corrientes Argentina A + + + XC10BVC -3, XC10BVC -4, XC10BVC -5 Orange Bella Vista, Corrientes Argentina A + + + XC10BVC -6, ACY-1215 molecular weight XC10BVC -7 Grapefruit Bella Vista, Corrientes Argentina A + + + XC10BVC-8 Tangerine Bella Vista, Corrientes Argentina A + + + XC6FT-1, XC6FT-2, XCT2, XCT3, XCT7, XCT9, XCT18, XCT22, XCT31, XCT33, XCT42 Lemon Leave Tucumán Argentina A + + + XCT1, XCT17, XCT19, XCT21, XCT28, XCT29, Lemon Fruit Tucumán Argentina A + + + XCT44 Tangerine Leave Tucumán Argentina A + + + 306 (sequenced strain) — – Brazil A + + + 625 — Aratiba, Sao Paulo Brazil A + + + 1637 — Embaúba, Sao Paulo Brazil A + + + 1740 — – China A + + + 1801 — – Oman A* + + + Xanthomonas fuscans subsp. Aurantifolii B832 — – Argentina B + + + 382,1473 — – Brazil Mannose-binding protein-associated serine protease C + + + Xanthomonas axonopodis pv. Citrumelo 1925 — – USA — – - – For each isolate CBC-LAMP reaction was performed in triplicate. When available, detailed data about the place of origin and type of sample is included. Gel: gel electrophoresis. LFD: lateral flow dipstick. SG: SYBRGreen.+: Positive
reaction.-: Negative reaction. The potential use of this technique in location was evaluated. Infected lemon and orange fruits and leaves were collected in field. All the field samples with canker symptoms gave positive reaction using all amplicon detection methods presented in this work (Additional file 1 fig. S1). Discussion Citrus Bacterial Canker is a serious, aggressive disease that attacks most species of citrus worldwide. Rapid and correct diagnosis of the pathogens is crucial to VE-822 clinical trial minimize and control damage to the citrus industry. During the last decade several nucleic acid amplification-based methods have been developed for the detection of CBC causing-Xanthomonas [4–8]. These methods are fast, specific and sensitive, but are not applicable for field trials, since they can require equipment and facilities that are not easily portable.