Abstract

Details are given of various laboratory methods for assessing fungicides for the protection of wet blue hides and evaluating storage margins in production wet blue leathers. Using these methods, a survey of nine commercial fungicide formulations applied to wet blue cuttings has been carried out. Products examined included a number previously found to fall into the low, medium and higher dosage levels (concentrations extending from 0.01 to 0.5% m/v in 100% float) to ensure four-month, residual protection. Experimental factors varied including fungicide addition point (pickle or rinse addition) and post-treatment wet blue handling (draining, rinsing, sammying and splitting). The treatment variations examined were aimed at gaining insight into uptake and penetration of the fungicides under practical conditions to improve prediction of field performance. Pickle addition of fungicide was found to give markedly improved storage protection in a number of cases. Post-treatment handling tended to reduce storage protection in effective products only at higher application levels in pickle addition. Decreases due to rinsing and sammying were comparable but tended to be greater after splitting, depending on the degree of fungicide penetration. Post-treatment effects were less marked in rinse application. The results indicate that more detailed assessment of fungicide effectiveness under various conditions in laboratory surveys can provide a better basis for prediction of field performance.