Variation of nut and kernel defects in Giresun quality tombul hazelnut cv. population

In this study, it was aimed to determine the changes in the defect rates of the fruits of Giresun Quality 'Tombul' hazelnut cultivar in the orchards in different locations. The study was conducted in Boztekke village, which has the highest production amount, production area and number of farmers in the central district of Giresun province (Türkiye). The variation of defective nut ratios (insect damaged on nut, brown stain, split sutures, small nut, multiple nut, blank nuts) and defective kernel ratios (abortive, shrivelled, double, fibrous, black tipped, moldy, insect pest in kernel) were investigated in the samples taken from the 9 different orchards. The study was planned as a randomized block design with 3 replications. As a result of the study, it was determined that the coefficients of variation of nut defects are higher than those of kernel defects in the population; the lowest nut defect was multiple nut, the highest defect was split sutures, the lowest kernel defect was double and the highest defect was shrivelled kernel. Kernel defects occurred at a slightly higher rate than nut defects and approximately ¾ of the total product was found to be defective. Kernel defects showed more variation among the orchards. Among the orchards, small and split sutures as nut defects, and double and abortive kernels as the kernel defects showed the highest variation. Total nut and kernel defect ratios and their sum and godd kernel ratios were significantly affected by orchards. On the other hand, it was also determined that the examined fruit pomological characteristics (nut and kernel weights, sizes, shell thickness, internal cavity and kernel percentage) showed a higher level of variation between orchards rather than within the population and the commercial kernel percentage, which is taken into consideration in product pricing, varied between 48.01-53.51% in the population, while the average was 50.63%.