Evaluation of genetic diversity in some hybrid individuals of honeyberry (Lonicera caerulea L.) based on fruit characteristics, leaf morphology, vitamin C, antioxidant activity, and biochemical and nutritional contents.

Background: Genetic diversity is a prerequisite for breeding programs, and one of the main goals here is to obtain quality products. Therefore, this study aims to evaluate the genetic diversity in some hybrid individuals of honeyberry (Lonicera caerulea L.) based on fruit characteristics, leaf morphology, vitamin C, antioxidant activity, biochemical, and nutritional content. In this context, superior quality individuals have been identified based on the 42 variables examined in our study. These hybrid individuals can be economically incorporated into production after the registration stages, and their sustainability for use in breeding programs can also be ensured.

Results: The fruit weight ranged from 0.71 ('H11') to 1.66 g ('H6'). The ascorbic acid varied between 17.13 ('H7') and 20.64 mg AAE/100 g ('H15'). The antioxidant activity changed between 12.59 ('Store') and 15.03 µmol Trolox g ('Aurea'). The total anthocyanins were found to be highest in 'Borrel Beast' (163.79 mg cyn-3-gluc 100 g), followed by 'H8' (163.20 mg cyn-3-gluc 100 g). The highest nutrient levels in the fruits were found in the 'H10' individual, with calcium (2445.77 mg kg), potassium (2274.36 mg kg), phosphorus (2123.27 mg kg), magnesium (1263.95 mg kg), and sulfur (859.62 mg kg), respectively. The highest nutrient levels in the leaves were found in the 'H14' individual for calcium (19,493.21 mg kg), 'H5' for magnesium (5643.52 mg kg), 'H8' for sulfur (2312.11 mg kg), 'H6' for phosphorus (2007.51 mg kg), and 'H6' for potassium (1099.32 mg kg). In general, the nutrients in the fruit exhibited significant correlations among themselves at different levels (*, **, ***). Within the scope of principal component analysis, the first 8 principal components explained 80.69% of the total variance. According to the cluster and population analyses, it was determined that there was a high variation in subgroup B2. Additionally, although honeyberry is a relatively new fruit in Türkiye, efforts have begun to develop new cultivars through hybrid breeding.

Conclusions: When 42 variables were evaluated together to determine genetic diversity, hybrid individuals 'H14', 'H5', 'H8', and 'H1' were identified as superior individuals, respectively.