Changes in the relationships between pomological characteristics in hazelnuts according to the picking manually from the branch and the ground

Abstract

This research was carried out to determine the relationships between pomological characteristics of hazelnuts collected manually from the branch and the ground. The research was carried out in three different orchards belonging to a producer, which contains Tombul, Foşa and Çakıldak hazelnut varieties in Kocaali district of Sakarya province (Türkiye). The orchards, located at an altitude of 300 m, face north. Hazelnut samples of Tombul, Foşa and Çakıldak varieties were collected from the branch in the first (2009) and second year (2010), on 12-15 August, 15-18 August and 22-25 August, respectively, and from the ground on 24-27 August, 27-30 August and 4-7 September, respectively. Nut weight, nut size, shell thickness, kernel weight, kernel size, kernel cavity, kernel percent, shriveled kernel ratio, good kernel ratio, full and average blanching ratios were determined in dried fruits. Correlation analysis was performed between the properties examined separately in the two groups of samples. In the samples collected from the branch and the ground, the highest variation was seen in the shriveled kernel ratio and the lowest in the good kernel ratio. It was determined that all of the significant correlation coefficients in the samples collected from the branch were positive, and the highest correlation coefficients were between full blanching ratio-average blanching ratio, nut weight-kernel weight and nut size-kernel size, respectively. In the samples collected from the ground, more significant correlations, and also negative significant relationships were found between the investigated properties. It was determined that the highest positive correlations were found between nut size-kernel weight, nut weight-kernel weight, full blanching rate-average blanching rate, nut weight-kernel size and nut size-kernel size, respectively; the highest negative correlations were found between the shell thickness-good kernel ratio, the shell thickness-kernel size, and the shriveled kernel ratio-good kernel core ratio, respectively. It can be said that the samples collected manually from the ground in hazelnut were more homogeneous than those collected from the branch in terms of the quality characteristics examined; in the samples collected from the ground, the good kernel ratio and kernel size were negatively affected by the shell thickness, the shriveled kernel ratio was positively affected, and there were no differences between the samples in terms of other relations.