Pest status of organic cucumber production under greenhouse conditions in İzmir (Turkey)

Abstract

The purpose of this study was to determine possibilities of cultivating organic cucumber under greenhouse conditions. Experiments according to principles and methods for organic agriculture were conducted in Ege University (Izmir-TURKEY), Faculty of Agriculture between 2003 and 2005 in a polyethylene (PE)-covered greenhouse (12.5 x 25 m) erected with galvanized steel hoops, with side and roof ventilation and covered with insect net. Cucumber (Cucumis sativus) cultivar “Sardes” was used as plant material. Trials were carried on during two successive spring and autumn growing periods. Cultural methods for pest management were applied before seedling transfer. Weeds and plant remains were removed carefully during growing period regularly. Sticky yellow traps, one per 10 m were hung 10 cm above the plants to monitor pests. Observations were made once a week in order to determine pests and diseases during the growing period. Plant diseases did not cause any significant problem during the growing seasons. Thrips, aphids, whiteflies, leafminers and spider mites were observed as pests. Whiteflies did not reach economic threshold. Damage due to leafminers was not important because of removal of the damaged leaves and yellow sticky traps. Aphids, thrips and spider mites caused significant injury sometimes and their injury level decreased by application of potassium soap 1-2 times a week. In addition, Aphidius colemani Viereck (Hymenoptera: Braconidae) was released to decrease aphid population. As a conclusion, yield data obtained in both growing seasons showed that spring growing season seems to be more appropriate for organic cucumber production in greenhouse conditions in Izmir.