Italy is one of the largest producers of Kiwi [Actinidia deliciosa (Chev.) Liang & Ferguson] and cv. Hayward is the most widespread. Over the past 10 years, especially in Northeastern and Central Italy, there was an increase in the cultivation of yellow kiwi (Actinidia chinensis Planchon) in which symptoms of bacterial canker caused by Pseudomonas syringae pv. actinidiae (Psa) have been reported in cultivations in the Lazio region. In Japan, China and Korea, major economic losses were caused by this bacterial disease that seriously damages all vegetative organs of the plant. The development of reliable diagnostic methods for asymptomatic materials is crucial for the activity of Plant Protection Services in order to confirm the presence of the pathogen in the territory and in marketing materials. Bacteria isolation from the fruits surface (31 samples cv. Hayward from Emilia Romagna region) and from their asymptomatic columellae to detect the presence of Psa was performed. As for the bacteria identification the following tests were carried out: fluorescent pigment production, HR in tobacco leaves, oxidase activity, acid production from sugars and molecular analysis (PCR-RFLP, REP-, BOX-PCR and Bio-PCR). The identification assays of the isolates obtained from the surface and columella fruits of all samples were negative for Psa. In order to discriminate Psa from the other kiwifruit pathogenic bacteria (i.e. Pseudomonas syringae pv. syringae and Pseudomonas viridiflava) and to confirm the isolates identification, the Psa pathogenicity was tested in fruits and kiwifruit plantlets. Moreover, Psa lives in the phyllosphere together with non-pathogenic bacteria that may interfere in the diagnosis of the bacterial canker by means of false negative or positive results. Therefore, from leaves and shoots of asymptomatic plants of Actinidia chinensis Hort 16A and Actinidia deliciosa cv. Hayward, collected from the Emilia Romagna region, epiphytic bacteria were isolated and studied.
Bacterial Canker of Kiwifruit (Actinidia spp.): Preliminary Bacteriological Studies in Asymptomatic Plant Materials in Northeastern Italy
MUCINI, SARA;BIONDI, ENRICO;LUCCHESE, CARLA;MAZZUCCHI, UMBERTO;MINARDI, PAOLA
2011
Abstract
Italy is one of the largest producers of Kiwi [Actinidia deliciosa (Chev.) Liang & Ferguson] and cv. Hayward is the most widespread. Over the past 10 years, especially in Northeastern and Central Italy, there was an increase in the cultivation of yellow kiwi (Actinidia chinensis Planchon) in which symptoms of bacterial canker caused by Pseudomonas syringae pv. actinidiae (Psa) have been reported in cultivations in the Lazio region. In Japan, China and Korea, major economic losses were caused by this bacterial disease that seriously damages all vegetative organs of the plant. The development of reliable diagnostic methods for asymptomatic materials is crucial for the activity of Plant Protection Services in order to confirm the presence of the pathogen in the territory and in marketing materials. Bacteria isolation from the fruits surface (31 samples cv. Hayward from Emilia Romagna region) and from their asymptomatic columellae to detect the presence of Psa was performed. As for the bacteria identification the following tests were carried out: fluorescent pigment production, HR in tobacco leaves, oxidase activity, acid production from sugars and molecular analysis (PCR-RFLP, REP-, BOX-PCR and Bio-PCR). The identification assays of the isolates obtained from the surface and columella fruits of all samples were negative for Psa. In order to discriminate Psa from the other kiwifruit pathogenic bacteria (i.e. Pseudomonas syringae pv. syringae and Pseudomonas viridiflava) and to confirm the isolates identification, the Psa pathogenicity was tested in fruits and kiwifruit plantlets. Moreover, Psa lives in the phyllosphere together with non-pathogenic bacteria that may interfere in the diagnosis of the bacterial canker by means of false negative or positive results. Therefore, from leaves and shoots of asymptomatic plants of Actinidia chinensis Hort 16A and Actinidia deliciosa cv. Hayward, collected from the Emilia Romagna region, epiphytic bacteria were isolated and studied.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
