Severe outbreak of curly parsley caused by autopathic effects [Petroselinum crispum (Mill.) Nyman ex A.W. Hill; Apulia]

English. In many Apulian cultivations, along the Adriatic coast, a serious decline of curly parsley was observed. Affected plants showed reduced growth and root system was poorly developed and lacking of neo-formed roots. Severe yellowing and drying on basal leaves were observed. Investigations about the parasitic nature of the decline were unsuccessful. Researches to ascertain the abiotic nature of disease were carried out and the effects of curly parsley plants extracts on vegetative development of plants cultivated in open field and on germination of seed were assessed. Tests about seed germination were carried out in Petri plate on Whatman filter imbibed with parsley extract at different concentrations. Plant extract was obtained after plant centrifugation (300 rpm). Plant extracts reduced the germinability and seed germinative energy and caused the alteration of the root apices. Effects of curly parsley on vegetative development were studied in open field. Fifty ml of parsley extract, obtained with the above described method, were applied around parsley seedlings before transplanting. These investigations let to confirm that the observed alterations in curly parsley cultivation were caused by autopathic effects of buried vegetal residuals after harvest on parsley successive culture

Italian. In numerosi impianti pugliesi, lungo il litorale adriatico, è stato osservato un grave deperimento del prezzemolo riccio. Le piante malate presentavano sviluppo ridotto e l'apparato radicale era scarsamente sviluppato e privo di radici di neoformazione. Le indagini sulla natura parassitaria del deperimento hanno dato esito negativo. In indagini di pieno campo è stata accertata la natura abiotica dell'alterazione e, in particolare, è stato dimostrato l'effetto autopatico di estratti di piante di prezzemolo riccio sullo sviluppo vegetativo. Gli estratti di piante di prezzemolo riccio hanno determinato anche la riduzione della germinabilità e dell'energia germinativa del seme e hanno provocato alterazioni dell'apice radicale del germinello