Post-harvest treatments by Epicoccum nigrum to control brown rot of stone fruits

• Published in: Journal of plant pathology Vol. 86; no. 4; p. 303
• Main Authors: Mari, M, Casalini, L, Melgarejo, P, De Cal, A, Larena, I, Linan, M, Mandrin, J-F, Mazollier, J, Bellini, A, Domenichini, P, Usall, J, Torres, R
• Format: Journal Article
• Language: English
• Published: 01-12-2004
• Subjects: Epicoccum nigrum; Monilia fructigena; Monilia laxa; Prunus
• ISSN: 1125-4653

Brown rot caused by Monilia laxa and Monilia fructigena is a serious disease found in all commercially grown Prunus species in European Mediterranean areas. Losses of economic importance result from infection to flowers and from fruit rot at harvest and in the postharvest phase. Pathogens are controlled by fungicide applications during fruit development. Postharvest treatments are not made in France, Italy and Spain. In the last 15 years, interest in disease management practices alternative to chemical pesticide applications has increased due to the need to eliminate chemical residues from the fruits. The potential of Epicoccum nigrum for the biological control of M. laxa in the orchards has been demonstrated elsewhere. Attempts to develop an effective and practical method for controlling brown rot disease by pre- and post-harvest Epicoccum treatments are described. Postharvest treatments were carried out in Spain, Italy and France. Naturally or artificially infected fruits were treated with E. nigrum fresh conidia or a formulate based on conidial paste. Concentrations of 10 super(6), 10 super(7), and 10 super(8) conidia ml super(-1) were tested for three years. After treatment, fruits were kept at 20 degree C and high humidity for 7 days. In postharvest trials carried out in Italy, a treatment with E. nigrum at the rate of 10 super(8) conidia ml super(-1) reduced significantly natural and artificial infections on nectarines with respect to untreated controls. Lower concentrations of fresh cells and formulate were less effective. No disease control was obtained in Spain and France (in these trials only 10 super(6) conidia ml super(-1) were tested). The effect of integration of pre-harvest E. nigrum treatments with physicochemical postharvest treatments was also evaluated on naturally infected fruits.