Research Information System
Thesis Type: Postgraduate
Institution Of The Thesis: Ankara University, Fen Bilimleri Enstitüsü, Bahçe Bitkileri, Turkey
Approval Date: 2021
Thesis Language: Turkish
Student: UĞUR ARMAN GÜLÇÜR
Supervisor: Veli Erdoğan
Abstract:
In this study, the effects of early and late harvest on the pomological and some chemical properties of Allahverdi, Çakıldak, Okay 28 and Tombul cultivars were investigated to determine the yield and quality losses due to early and late harvest. The study was carried out in Hazelnut Research Institute, Giresun at coastline and Department of Horticulture, Faculty of Agriculture, Ankara University, in 2019. The nuts were harvested at one-week intervals on a total of six dates in Allahverdi, Okay 28 and Tombul cultivars (16, 23 and July and 6, 13, 20 August), and on a total of seven dates (27 August) in Çakıldak cultivar as they matured later. At coastline, the harvest dates of 6 and 13 August for Allahverdi and Tombul cultivars, 6 August for Okay 28 cultivar and 13 and 20 August for Çakıldak cultivars were determined based on the criteria of husk coloration, formation of shell color specific to cultivar, the beginning of nut movement in the husk, browning of the nut base and the falling off the clusters. However, husk coloration was not very decisive for harvest date except for the Tombul cultivar. In all the cultivars, due to too early or early harvest, inshell and kernel weight, kernel size and yield (and/or oil) were low causing yield loss. The most affected quality parameter was blanching that there was no or little blanching in early harvest dates. Negative effects of late harvest were observed in Okay 28 cultivar by increased rates of split nuts, black-tips and mold in kernels hence decreased rates of sound nuts. Blanks, double kernel and insect damage were not associated with harvest date. Harvesting on the onset of cluster fall off is suggested to minimize yield and quality loss.