title: Influence of post-harvest application rates of cyprodinil, treatment time and temperature on residue levels and efficacy in controlling green mould on 'Valencia' oranges.
abstract: The effectiveness of heat treatments with water and cyprodinil in controlling post-harvest green mould caused by Penicillium digitatum was investigated on artificially inoculated 'Valencia' oranges. Residue levels of cyprodinil were determined in the oranges as a function of active ingredient concentration, temperature and treatment time. Cyprodinil residues were significantly dependent on treatment time when applied at 600 mg l(-1) and 20 degrees C, but not when fruit were treated at 150-300 mg l(-1). The application of cyprodinil at 50 or 100 mg l(-1) at 55 degrees C for 30 s produced similar residue levels, while residues increased when the application rate was 150 mg l(-1). Cyprodinil at 100 mg l(-1) and 60 degrees C produced a significant increase in residues compared to treatment at 50 mg l(-1); no significant increase in residues was found when the application rate was raised from 100 to 150 mg l(-1). In comparison to treatments performed at 20 degrees C, the application of a heated cyprodinil mixture resulted in significantly higher residues in fruit. All treatments with cyprodinil at 20 degrees C similarly reduced green mould after 7 days of storage at 20 degrees C. After 18 days, treatment with cyprodinil at 600 mg l(-1) for 30 s was more effective than at 150-300 mg l(-1). When dip time was extended to 90 or 180 s, treatment efficacy was positively related to fungicide concentration. Treatments with water at 55 degrees C for 30 s were as effective as cyprodinil at 50-100 mg l(-1), but less effective than cyprodinil at 150 mg l(-1). After 7 days, treatment with water or cyprodinil at 50-150 mg l(-1) and 60 degrees C were equally effective in controlling green mould; while, after 18 days, treatment with cyprodinil at 150 mg l(-1) was consistently more effective than at 50-100 mg l(-1) or hot water alone.
authors.affiliation: Institute of Sciences of Food Production, National Research Council, Sassari, Italy. mario.schirra@ispa.cnr.it
authors.forename: Mario
authors.initials: M
authors.lastname: Schirra
authors.forename: Salvatore
authors.initials: S
authors.lastname: D'Aquino
authors.forename: Paolo
authors.initials: P
authors.lastname: Cabras
authors.forename: Alberto
authors.initials: A
authors.lastname: Angioni
mesh_terms: D002849:Chromatography, Gas / Q000379:methods; D032084:Citrus sinensis / Q000382:microbiology*; D005519:Food Preservation / Q000379:methods; D005659:Fungicides, Industrial / Q000032:analysis*; D006358:Hot Temperature; D007558:Italy; D010407:Penicillium / Q000187:drug effects*; D010573:Pesticide Residues / Q000032:analysis; D011743:Pyrimidines / Q000032:analysis*; D013997:Time Factors
chemical_list: D005659:Fungicides, Industrial; D010573:Pesticide Residues; D011743:Pyrimidines; C108338:cyprodinil