[Effect of pre-harvest fungicides and types of packaging, on apricots (Prunus armeniaca, L.) cultivar Modesto]

In the present trial, the effect of five preharvest fungicides, three packaging types and two maturity degrees were evaluated in the storage of Modesto apricots, for fresh export. Dichloran, Captan, Iprodione, Vinclozolin and Benomyl-Captan fungicides were applied before harvest, according to USA carencies. Also control trees were selected, with no fungicide application. Once the fruit was harvested, it was divided into two groups according to their maturity degree, and then packed in export one-tray cartons. In one packaging type, the tray was without protection; in the second one, the try was wrapped by a plastic film, and in the last one, it was inside a plastic bag. Finally all the boxes were cold storaged at 0 deg C and 85-90% R.H. Four evaluations were made, at fifteen days of cold storage intervals, with two measuring times: just after leaving storage and after three days at room temperature. In each evaluation, existing pathogens were identified and the following parameters were measured: mycosis (%), dehydration (%) and damages. Also, residue analyses at harvest were made for each fungicide, as well as degradation curves in cold storage for Dichloran and Iprodione. Among the results of the trial, remarkable differences were observed between the infection levels detected in the control and the fungicide treatments. The best results were obtained with Dichloran and Iprodione. None of the fungicides produced phytotoxicity or exceeded the USA tolerances. Botrytis cinerea was the most commonly identified pathogen in this trial and therefore it was considered as the main decay-causing organism in postharvest apricots. In relation to the packaging types, plastic film proved to be the most suitable one. The use of packaging without protection was discarded because of the higher levels of dehydration that it produced. The use of plastic bag was also discarded for presenting the highest infection levels. The lowest maturity degree, presented lower levels of dehydration, infection and damages. It is concluded that apricot fruit cv Modesto held from 35 to 40 days under cold storage presents acceptable dehydration and decay levels