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In Croatia, the common fig (Ficus carica L.) is one of the oldest cultivated fruit trees, commonly present in family orchards. Significant efforts have been made lately to collect national genetic resources to ensure their long-term conservation in ex situ collections, and thus, their sustainable management. In Croatia there are two ex situ fig germplasm collections, with 22 accessions officially registered in the Croatian Plant Genetic Resources Database. The aim of this study was to characterize the collections and to assess the genetic diversity of collected fig germplasm. A set of 90 accessions from Croatian collections and six reference samples from a Slovenian database were genotyped using five SSR markers. A total of 24 alleles were detected, with the observed number of alleles per locus ranging from three (FCUP- 016-6) to seven (FCUP-038-6) with an average of 4.8 alleles per locus. The UPGMA clustering analysis discriminated 31 genotypes and revealed five groups of accessions. In total, 77 duplicated accessions, 11 new genotypes, and 20 cases of homonymy and synonymy have been determined. The genetic relationships among Croatian traditional fig cultivars have been assessed. Results obtained in this study can be used for germplasm conservation, breeding programs, nursery production improvement, and for optimizing the national strategy for the management of fig genetic resources.

In recent years, Slovenian olive growers and producers have faced problems in achieving constant yields and quality of olive oil due to extreme weather conditions, especially because of the more frequent occurrence of drought. A technically accomplished pilot automatic irrigation system for olive trees was established. In 2015, the impact of different irrigation treatments (0, 15, 33, 40 and 100% ETc (crop evapotranspiration)) on olive cultivar 'Istrska belica' were studied to determine the minimum amount of added water that has a positive effect on the yield and quality of the extra virgin olive oil produced. The study results showed that the quantity of applied water equal to 100% ETc had a significant effect on yield of olive fruits. The average fruit mass of the trees grown under full irrigation (100% ETc) was significantly higher than that of those given rain-fed and deficit irrigation treatments (15, 33 and 40% ETc), with no significant differences found between these treatments. The fatty acid contents showed the highest amount of oleic acid (75.61%) at 100% ETc and the lowest amount (74.69%) at 15% ETc, while the highest amount of linoleic acid (6.52%) was determined at 15% ETc and the lowest (5.98%) at 100% ETc. Total biophenol content and biophenol composition was determined. The 40% ETc irrigation system produced the highest amounts of total biophenols, total oleuropein and total ligstroside derivatives (1076, 562 and 388 mg kg-1, respectively), while the lowest results (883, 477 and 299 mg kg-1, respectively) were determined in the control system (0% ETc). The organoleptic assessment of the olive samples showed that the positive sensory attributes of fruity, bitter and pungent were more intensive at 33% ETc and were graded highest. Olive oil from non-irrigated trees (0% ETc) received the lowest sensory score.

Sugars, the primary metabolites of plants, play an important role in the process of olive ripening, as they provide energy for metabolic changes and serve as a source for the biosynthesis of fatty acids. Phenolic compounds, which are secondary metabolites, can be synthesized in plants as a reflection of stressful situations such as tissue damage and UV irradiation. The objective of this study was to assess the impact of different irrigation treatments (0, 15, 33, 40, and 100% crop evapotranspiration (ETc)) on primary metabolites (sugars, sugar alcohols) and secondary metabolites (phenolic compounds). In different phenological periods, the levels of oleuropein, sugars and sugar alcohols were determined in olives and leaf samples in the crop years 2014, 2015, and 2016. The levels of oleuropein in olive fruits and leaves were highest under the irrigation treatment of 40% ETc and decreased noticeably under the irrigation treatment of 100% ETc. The median levels of glucose were higher compared with the mannitol and fructose levels in olive fruits. Total determined sugars in olive fruits during maturation decreased. While significant correlations were found in olive fruits between determined sugars and sugar alcohols and different irrigation treatments, we did not observe any correlation between determined sugars and sugar alcohols in olive leaves and irrigation treatments. Our research confirmed the complexity of the content of oleuropein and sugars or sugar alcohols in the leaves and fruits of olive trees from Slovenian Istra, which depend on various factors, not just drought stress. Weaker and less obvious correlations between the studied compounds and drought stress might be a consequence of unusual rainfall in the studied crop years.