Adding sanitisers to aqueous fungicides solutions in citrus fruit packinghouses is beneficial for disease control

Sanitisers added to drench solutions reduce accumulation?of sour rot (GC; Geotrichum citri-aurantii) inoculum.Hypochlorous acid (HClO) and peracetic acid (PAA) were?compared during in vitro, in vivo and commercial packhouse?trials in typical South African drench solutions [thiabendazole?(TBZ) + pyrimethanil (PYR) + 2,4-dichlorophenoxyacetic?acid (2,4-D)]. Effects on green mould (PD; Penicillium digitatum)?and GC control, ability of the sanitisers to reduce?microbial load (CFU mL-1) in drench solutions and fungicide?persistence for effective PD control were investigated. In?commercial packhouse trials PD infection was reduced from??78.3% to ?67.7% following fungicide drench application.?Fungicide persistence was similar regardless of sanitiser?treatment. During in vitro trials the sanitisers did not affect?fungicide concentration levels. PAA completely eliminated?GC inoculum (0.0 CFU mL-1) after 1-3 min at high pH levels?(>10). During in vivo trials residue levels, solution concentration?and PD control were similar between sanitiser?treatments and those to which dirt (kaolin) were added.PAA treatments improved GC control on Valencia orange?and Nadorcott mandarin fruit and improved PD control on Nadorcott mandarin fruit. Exposure to 0.3% HPPA for 3 min?was superior to HClO treatments. Adding sanitisers to aqueous?fungicides solutions are beneficial for disease control. Sources SANITISATION OF FUNGICIDE DRENCH SOLUTIONS AND?EFFECTS ON GREEN MOULD AND SOUR ROT CONTROL IN CITRUS?Erasmus A1,3, Christie C2, Lennox CL2, Savage C1 & Fourie?PH1,2 1Citrus Research International, Nelspruit, South Africa;2Department Plant Pathology, Stellenbosch University,?South Africa; 3Current address: Wonderful Citrus, Delano,?CA, USA; e-mail: arno.erasmus@wonderful.comInternational Citrus Congress 2016The picture belongs to?Pintarest