Influence of formulation and application method on the effectiveness of benzimidazole fungicides for controlling postharvest diseases of citrus fruits

Abstract

Treatment of citrus fruits after harvest with benzimidazole fungicides suspended in water or incorporated in wax formulations can control the development of several diseases of the fruit during storage and marketing. Residues of I mg fungicide/kg fruit are sufficient to retard the development of latent infections of Phomopsis and Diplodia and to prevent wound infection by Penicillium spp. Sporulation of Penicillium spp. on the surface of decayed fruit, a serious problem in long distance shipment of citrus fruits, can be controlled by minimum residues of 2-6 mg fungicide/kg fruit, depending upon the composition of the residues on the fruit. On an equivalent residue basis, benomyl is considerably more effective than thiabendazole or methyl benzimidazol-2-ylcarbamate (MBC) in reducing sporulation of Penicillium on treated fruit. Benomyl appears to penetrate into the flavedo tissue of the orange whereas residues of MBC and thiabendazole are limited to the surface of the fruit. The effectiveness of the benzimidazole fungicides is not influenced by the variety or size of citrus fruits but is significantly affected by the formulation and method of application. MBC and thiabendazole are stable under most conditions of formulation and application but benomyl breaks down in alkaline wax formulations and in organic solvent formulations. Deposits of thiabendazole on fruit resulting from application of a waterwax formulation are less effective in controlling sporulation than an equivalent deposit applied as a suspension in water.

Effectiveness of Trichoderma strains isolated from the rhizosphere of citrus tree to control Alternaria alternata , Colletotrichum gloeosporioides and Penicillium digitatum A21 resistant to pyrimethanil in post‐harvest oranges ( Citrus sinensis L. (Osbeck))

“…Typically, most of the approaches involve applications of different synthetic fungicides, especially in post‐harvest stage, such as imazalil (IMZ), thiabendazole (TBZ), pyrimethanil (PYR), sodium orthophenyl phenate and fludioxonil, among many others (Zacarias et al 2020). First reports about extensive applications of benzimidazole fungicides such as TBZ in citrus date from 1970s (Baker and Hoodless 1973; Eckert and Kolbezen 1977). Since then, these fungicides have been used in a continuous and sometimes inadequate manner, producing the proliferation of resistant strains of P. digitatum and P. italicum few years after its implementation (Eckert and Eaks 1989; Bus et al 1991).…”

Natural extracts in plastic food packaging

“…In China, wax has been used to retard desiccation of citrus fruits since the twelfth and thirteenth centuries (Hardenburg, 1967). In the last three decades, application of fungicides including benomyl, imazalil and thiabendazole in wax coating has been studied primarily on citrus fruits (Brown, 1974;Eckert and Kolbezen, 1977;Brown et al, 1983). For coating film formation, there are many techniques (e.g.…”

Effectiveness of pH and Butylated Hydroxyanisole (BHA) on Fungicidal Activity of Certain Fungicides for Controlling Green and Blue Mold Diseases on Orange Fruits

“…After drying, the fruits were inoculated artificially with P. digitatum or P. italicum. Inoculation was performed according to Eckert and Kolbezen (1977) by making a scratch 1.0 cm long and 0.1 mm deep in the rind on both sides of each fruit and then applying dry spores dust to the scratches with a small brush. Twenty four hours after inoculation, orange fruits were treated with the tested fungicides and BHA and their mixtures by using dipping method in the solutions for 30 sec.…”