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Under stress or in optimum conditions, plants foster a specific guild of symbiotic microbes to strengthen pivotal functions including metabolic regulation. Despite that the role of the plant genotype in microbial selection is well documented, the potential of this genotype-specific microbial assembly in maintaining the host homeostasis remains insufficiently investigated. In this study, we aimed to assess the specificity of the foliar metabolic response of contrasting olive genotypes to microbial inoculation with wet-adapted consortia of plant-growth-promoting rhizobacteria (PGPR), to see if previously inoculated plants with indigenous or exogenous microbes would display any change in their leaf metabolome once being subjected to drought stress. Two Tunisian elite varieties, Chetoui (drought-sensitive) and Chemleli (drought-tolerant), were tested under controlled and stressed conditions. Leaf samples were analyzed by gas chromatography–mass spectrometry (GC-TOFMS) to identify untargeted metabolites. Root and soil samples were used to extract microbial genomic DNA destined for bacterial community profiling using 16S rRNA amplicon sequencing. Respectively, the score plot analysis, cluster analysis, heat map, Venn diagrams, and Krona charts were applied to metabolic and microbial data. Results demonstrated dynamic changes in the leaf metabolome of the Chetoui variety in both stress and inoculation conditions. Under the optimum state, the PGPR consortia induced noteworthy alterations in metabolic patterns of the sensitive variety, aligning with the phytochemistry observed in drought-tolerant cultivars. These variations involved fatty acids, tocopherols, phenols, methoxyphenols, stilbenoids, triterpenes, and sugars. On the other hand, the Chemleli variety displaying comparable metabolic profiles appeared unaffected by stress and inoculation probably owing to its tolerance capacity. The distribution of microbial species among treatments was distinctly uneven. The tested seedlings followed variety-specific strategies in selecting beneficial soil bacteria to alleviate stress. A highly abundant species of the wet-adapted inoculum was detected only under optimum conditions for both cultivars, which makes the moisture history of the plant genotype a selective driver shaping microbial community and thereby a useful tool to predict microbial activity in large ecosystems. [ABSTRACT FROM AUTHOR]

Under stress or in optimum conditions, plants foster a specific guild of symbiotic microbes to strengthen pivotal functions including metabolic regulation. Despite that the role of the plant genotype in microbial selection is well documented, the potential of this genotype-specific microbial assembly in maintaining the host homeostasis remains insufficiently investigated. In this study, we aimed to assess the specificity of the foliar metabolic response of contrasting olive genotypes to microbial inoculation with wet-adapted consortia of plant-growth-promoting rhizobacteria (PGPR), to see if previously inoculated plants with indigenous or exogenous microbes would display any change in their leaf metabolome once being subjected to drought stress. Two Tunisian elite varieties, Chetoui (drought-sensitive) and Chemleli (drought-tolerant), were tested under controlled and stressed conditions. Leaf samples were analyzed by gas chromatography–mass spectrometry (GC-TOFMS) to identify untargeted metabolites. Root and soil samples were used to extract microbial genomic DNA destined for bacterial community profiling using 16S rRNA amplicon sequencing. Respectively, the score plot analysis, cluster analysis, heat map, Venn diagrams, and Krona charts were applied to metabolic and microbial data. Results demonstrated dynamic changes in the leaf metabolome of the Chetoui variety in both stress and inoculation conditions. Under the optimum state, the PGPR consortia induced noteworthy alterations in metabolic patterns of the sensitive variety, aligning with the phytochemistry observed in drought-tolerant cultivars. These variations involved fatty acids, tocopherols, phenols, methoxyphenols, stilbenoids, triterpenes, and sugars. On the other hand, the Chemleli variety displaying comparable metabolic profiles appeared unaffected by stress and inoculation probably owing to its tolerance capacity. The distribution of microbial species among treatments was distinctly uneven. The tested seedlings followed variety-specific strategies in selecting beneficial soil bacteria to alleviate stress. A highly abundant species of the wet-adapted inoculum was detected only under optimum conditions for both cultivars, which makes the moisture history of the plant genotype a selective driver shaping microbial community and thereby a useful tool to predict microbial activity in large ecosystems.

This is the first study evaluated oil characteristic of 23 olive cultivar candidates, which obtained by cross breeding and later selection among 492 olive genotypes. In this research, oil characteristics such as alfa tocopherol, total phenol, antioxidant activity, oxidative stability and sensory analysis were determined. Olive oils of standard 'Gemlik' and 'Ayvalık' cultivars were also included analysis to compare candidates. Significant genetic influence was determined on nutritional, oxidative stability and sensory characteristics of oils. Oils of GT009, LE003 and LT019 genotypes had highest both total phenol content and antioxidant activity so that they had remarkable characters from nutritional physiology perspective. GE363 showed longest induction time and LE003, GE417 and GE363 showed longest shelf life. Highest alpha tocopherol content was determined in oils of BK013 and 'Gemlik' olives. According to sensory evaluation, oil of GU429 was classified as well balanced oil and oils of GE067, GE110, GE366, GU247, GU320, GU323 and GU434 classified as mild oil. These results will be used to give decision for their final selection and register the selected best cultivar candidates. [ABSTRACT FROM AUTHOR]

This is the first study in Turkey that evaluated olive fruit and oil characteristics of 23 cultivar candidates selected among 393 olive genotypes, on the bases of agronomical characteristics; the candidate cultivars were obtained by cross breeding between standard cultivars (‘Gemlik’, ‘Edinciksu’, ‘Uslu’, ‘Tavşan Yüreği’, ‘Karamürselsu’) and foreign cultivars (‘Lucques’, ‘Belle d’Espagne’ and ‘Manzanilla’). Fruit traits such as fruit weight, flesh to seed ratio, fruit and seed size, as well as oil characteristics such as moisture, oil content, specific absorption at ultraviolet light, free acid content, peroxide value, chlorophyll and fatty acid composition were determined. Fruits and oils of intensely cultivated ‘Gemlik’ and ‘Ayvalık’ olive cultivars were also analyzed to compare them with the new candidate cultivars. According to the oil content, ‘GE067’ (23.30%), ‘GE181’ (23.97%), ‘GE366’ (22.52%), ‘GE417’ (22.16%), ‘GT009’ (24.14%), ‘GT014’ (21.02%), ‘GU247’ (22.48%), ‘GU320’ (27.15%) and ‘GU434’ (21.89%) gave better results, thus having good potential for registration as new cultivars for oil production. ‘GE366’ and ‘GU434’ were determined as the best cultivar candidates for producing dual purpose olives (table olives and oil). ‘GE363’ had the best fatty acid composition, which is an important feature in terms of oxidative stability and disease prevention.

Genetic variation was reported as an important factor effects quality of table olive. So that researchers aimed to develop new cultivar which had high table olive characteristics than that's of standard cultivar. This research was aimed to determine characters of raw and processed fruits of 4crossedolive genotypes which had been reported by previous studies as promising cultivar for registration according to agronomic characteristics. Fruits of Manzanilla cultivar which is the most important green table olive cultivar in Spain were used for comparison. Number of olives per kilogram, flesh to seed ratio, water, oil, total and reducing sugar, and phenolic compounds were analyzed. Sensory and salt analyses also were applied to processed olives. For green table olive production; olives were debittered by 2% NaOH and then put in brine which contained 5% salt at pH4,5. At 4th day of keeping the olives in brine, 107CFU/mL Lactobacillus plantarum were inoculated to the brine for fermentation until pH fall to 3,8.All the olives of genotypes had enough reduced sugar content (>2 %) for fermentative microorganisms and higher olive weight than Manzanilla but only olive of BK013 had higher flesh to seed ratio than Manzanilla. After processing hydroxytyrosol losses were determined in the range of 30,25-88,88 % and processed olives of MT038 had higher hydroxytyrosol content this is precious for nutrition physiology of consumer. Olives of BK013 and GK131had bettertable olive and sensory characteristics so that they have potential for registration as new table olive cultivar. [ABSTRACT FROM AUTHOR]

In this research, 14 hybrid table olive genotypes were used as material which were harvested from Olive Breeding Parcels in Atatürk Central Horticultural Research Institute (Yalova/TURKEY) and their maturation index, oil content, fatty acid composition and omega-6:omega-3 fatty acid ratio were evaluated. These genotypes were generated by crossing Gemlik, Manzanilla, Ascolana, Edinciksu, Uslu, and Tavşan yüreği olive cultivars during cross breeding studies of a national project. Oil was obtained from fruit of olive genotypes by cold pressing. Maturation index and oil content of genotypes were determined between 2.6-6.4 and 22.43-28.12 (%). Linolenic acid distributions in fatty acid composition of genotype's oil were detected between 0.5-1.33 (% in fatty acids). Some olive genotypes' oils had high linolenic characteristics that they have potential for supporting the necessary intake of omega-3. Also, some of them have had the desired omega-6/omega-3 fatty acid ratio which were between 3.74 and 4.00. Practical applications: Olive oil is a traditional product of Mediterranean basin and commonly consumed all over the world. But there is a need to improve yield, quality and nutritional value of olive oil. For this reason, there breeding studies were conducted. One of them was carried out in Ataturk Central Horticultural Research Institute. Here domestic and foreign olive cultivars were crossed to generate new olive genotypes since 1990. This research aimed to determine the olive oil of these obtained olive genotypes which had higher oil and omega-3 content and lower omega-6:omega-3 fatty acid ratio. Generating the high omega-3 content olive oil by cross breeding is one of the cheapest, simplest and most natural ways of obtaining omega-3 and delivering it to the consumer. [ABSTRACT FROM AUTHOR]