Müge Şahin

Characterizing the flowering behavior and thermal requirements of quince (Cydonia oblonga Mill.) genotypes is essential for guiding future breeding efforts and adapting cultivation practices under ongoing climate change. However, there is a lack of comprehensive data on quince flowering phenology and associated thermal requirements. In this study, we investigated the bud and flowering phenology of 47 quince genotypes originating from Türkiye over three consecutive seasons under Mediterranean climate conditions. Phenological stages including bud break, bud burst, first bloom, full bloom, and end of bloom were recorded and expressed as day of the year (DOY), while effective flowering period and heat requirements were also calculated. Genotype and year had a significant influence on all phenological traits recorded. Bud break was observed as early as DOY 44, and flowering ended by DOY 108.3. Effective flowering periods ranged from 3.30 to 7.67 days, with genotype 2423 exhibiting both the earliest bloom and the longest effective flowering period. Heat accumulation between BBCH code 07 (bud break) and BBCH stage 65 (full bloom) was calculated in terms of growing degree days (GDD: 151.42–236.42) and growing degree hours (GDH: Anderson: 4,770.57–7,570.56; Richardson method: 5,444.47–8,028.20). Genotypes such as 2162 required the least heat input, while genotypes like 2760 showed the highest thermal demand for flowering. This study represents the most extensive classification of flowering phenology and heat requirement in quince to date. Results offer critical insights for selecting climate-resilient genotypes, identifying suitable cultivation zones, and supporting varietal registration through standardized flowering class assignments aligned with UPOV guidelines.

The susceptibility of apples to post-harvest decay by the fungus Botrytis cinerea has prompted innovative research into alternative preservation methods. In this regard, essential oils (EOs) have emerged as promising candidates due to their natural origin and potential antimicrobial properties. Investigating the biological significance of EO blends is crucial for understanding their potential antimicrobial mechanisms and evaluating their capacity to modulate metabolic responses that could inhibit post-harvest fungal decay in fruit tissues. This study delves into the intricate chemistry of apples when subjected to various EO treatments, shedding light on the profound changes in alcohols, esters, C6 compounds, terpenes, and volatile compounds. Based on our results, terpene concentrations exhibit significant variations with α-Pinene ranging from 13.4 µg L⁻¹ in Fungus + Thymol + 1,8-Cineole treatment (Fun+Thy+Cin) to 28.7 µg L⁻¹ in Fungus + Thymol + 1,8-Cineole + Eugenol treatment (Fun+Thy+Cin+Eug), and β-Pinene concentrations spanning 19.3 µg L⁻¹ in Fungus + 1,8-Cineole + Eugenol treatment (Fun+Cin+Eug) to 45.5 µg L⁻¹ in Fungus + Thymol + 1,8-Cineole + Eugenol treatment (Fun+Thy+Cin+Eug). Ester elaboration presents marked changes, with ethyl octanoate peaking at 715.7 µg L⁻¹ in Fungus + Thymol + 1,8-Cineole + Eugenol treatment (Fun+Thy+Cin+Eug) and ethyl propionate reaching 152.9 µg L⁻¹ in Fungus + Thymol treatment (Fun+Thy). The volatile compound dynamics also demonstrate significant variations, with hexanoic acid concentrations ranging from 0.1 to 0.2 among treatments and 3-Methylbutanal displaying concentrations from 0.8 to 6.4, with the highest concentration observed in the Control. The essential oil combination of Thymol, Eugenol, and 1,8-Cineol (Fun+Thy+Cin+Eug) had the most significant impact on the volatile compound content in the fruits. The findings from this study unveil the intricate responses of apple chemistry to various EO treatments. These insights hold promise for enhancing post-harvest apple preservation strategies through the modulation of EO treatments.

A greater genetic diversity is essential for disease resistance in particular, and intergeneric hybridization makes this possible. The genus Cydomalus (syn: Cydolus), which is frequently used as rootstock, was derived from intergeneric hybridization between Cydonia oblonga Mill. and Malus domestica Borkh in Moldova and Bulgaria. It is known that hybrids from this genus exhibit quince and/or apple characteristics and some of them have been identified with reddish fruit skin color in Türkiye in the last decade. Erwinia amylovora Burril. is the most devastating bacterial disease in the Rosaceae family, and there have been no reports of Cydomalus. In this study, fire blight susceptibility index of three Cydomalus genotypes, were collected from İzmir and Manisa provinces, and two important quince rootstocks were determined by artificial inoculations with the most virulent Erwinia amylovora strain of our collection, under greenhouse conditions for two consecutive years. In addition, susceptibility levels of two Cydomalus genotypes were observed under natural disease pressure habitats. In line with the results of artificial inoculations, two of Cydomalus genotypes were determined to be more tolerant to fire blight disease than quince rootstocks and these genotypes could be used in breeding studies. Moreover, Cydomalus genus was identified as the new host for Erwinia amylovora.

Unraveling the intricate physiological and biochemical intricacies associated with female dominance in grape berries across diverse developmental stages is imperative for optimizing grape production and ensuring the attainment of high-quality yields. This study conducted a thorough analysis of grape berries across phenological stages (BBCH-79, BBCH-81, BBCH-89) and cultivars. At BBCH-89, Bozcaada Çavuşu*Vasilâki demonstrated the highest berry weight and total soluble solids (TSS) levels, emphasizing its enological potential. Acidity peaked at BBCH-79 (28.16) and declined at BBCH-89 (6.11), signaling a shift towards lower acidity in later stages. Bozcaada Çavuşu*Vasilâki consistently showed the highest maturity index (MI). Mineral content variations were observed across nitrogen (N), calcium (Ca), potassium (K), phosphorus (P), magnesium (Mg), sulfur (S), iron (Fe), manganese (Mn), boron (B), zinc (Zn), and copper (Cu), with Bozcaada Çavuşu*Vasilâki often having the highest concentrations, particularly in potassium, calcium, and boron. Hormonal analysis revealed a significant surge in concentrations at BBCH-89, with Bozcaada Çavuşu*Vasilâki standing out. Notably, Indole-3-acetic acid (IAA) concentrations increased by 106%, and abscisic acid (ABA) levels peaked at BBCH-79 with a 38% increase in Bozcaada Çavuşu*Kuntra. Sugar content analysis showed variations in fructose, glucose, sucrose, rhamnose, xylose, galactose, and arabinose levels across sampling times and cultivars. Bozcaada Çavuşu*Vasilâki consistently exhibited higher sugar levels, especially at BBCH-81 and BBCH-89. Vitamin concentrations varied temporally and among cultivars, with BBCH-89 displaying the highest vitamin A concentration (6.24 mg/100 g FW), and Bozcaada Çavuşu*Vasilâki often exhibiting maximum values for vitamin B1, B2, B6, and C. Further research and targeted cultivation practices focusing on the unique attributes of Bozcaada Çavuşu*Vasilâki could enhance grape production efficiency, emphasizing its potential contribution to achieving consistently high-quality yields across various phenological stages.

Understanding the impact of pre-treatment methods on the phytochemical composition of grapes is essential for optimizing grape quality and producing raisins with desirable characteristics. Therefore, this study meticulously analyzed the impact of two distinct pre-treatment methods, oak ash and potassium carbonate (K₂CO₃), on the composition of essential phytochemical components in grapes. This research encompassed phenolic compounds, anthocyanins, phenolic acids, flavonoids, and phytoalexins. This study investigates the impact of pre-treatment methods, oak ash and K₂CO₃, on the phytochemical composition of grapes. Significant differences were observed in anthocyanins, flavonoids, phytoalexins, and phenolic acids between the treatments. Oak ash exhibited advantages in preserving specific compounds, including higher levels of anthocyanins, flavonols, flavones, flavanones, catechins, resveratrol, pterostilbene, and viniferin, compared to K₂CO₃. Notably, the delphinidin-3-O-glycoside content was significantly higher in the oak ash treatment. An analysis of phenolic compounds revealed distinctions in hydroxycinnamic acids, hydroxybenzoic acids, benzaldehyde, and phenylacetaldehyde. Additionally, gallic acid, vanillic acid, trans-caffeic acid, trans-p-coumaric acid, and (-)-epicatechin were significantly more prevalent in the K₂CO₃ treatment, while ferulic acid and quercetin were more prevalent in the oak ash treatment. These findings underscore the pivotal role of pre-treatment methods in shaping the phytochemical content of grapes, thus holding critical implications for grape-derived products’ quality and potential health benefits.

In this study, newly formulated gluten-free chips with almond powder were produced. Almond powders were obtained using 3 different drying methods: oven drying, freeze drying, and microwave drying. This study aimed to determine the effect of drying almond powders used in gluten-free chip production using different drying methods and then adding different ratios (10% and 30%) of these powders to the chips on the physicochemical, textural, mineral, and sensory properties of the chips. The physical, textural, mineral, and sensory analyses were then carried out. The moisture content values of the chips with almond powder were < 6.32% and the water activity values were < 0.300. Adding almond powder increased the total fat and protein content of the chip samples. The protein content of the gluten-free chips increased by 34.69-257.14% compared to the control sample and the highest protein content (1.75%) was determined in the samples containing 30% of the almond powder obtained using the microwave drying method. The hardness of the gluten-free chips decreased by increasing the almond powder. The addition of the almond powder to the chip formulation generally increased the B, Cu, Mn, and Zn contents of the gluten-free chips. All chip samples enriched with almond powder showed similar overall acceptability scores (5.00-6.89).

Hünnap (Ziziphus jujuba Mill.) 4.000 yıl önce Çin de kültüre alınan, günümüzde ise başta Çin olmak üzere Orta Asya, Avrupa ve Avusturalya’da geniş yayılım gösteren bir bitkidir. Bu çalışmada Denizli İli Çal İlçesinin farklı lokasyonlarından belirlenen 17 hünnap genotipinin, 2021 ve 2022 yıllarında meyve tutum oranları belirlenmiştir. Her genotip için 3 tekerrür ve her tekerrürde 3 sürgün olacak şekilde deneme planlanmış ve her sürgündeki çiçek sayıları ve sonrasında da meyve sayıları belirlenerek meyve tutum oranları hesaplanmıştır. Yapılan istatistiksel değerlendirmeler sonucunda, sürgündeki çiçek sayısı hariç diğer parametrelerde yıllar arasındaki farklılık istatistiksel olarak önemli olarak belirlenmiş (P≤0,0001). 2021 yılında en yüksek veriler elde edilmiştir. Sürgündeki ortalama çiçek adeti 2021 yılında 10,70 ile 56,10, 2022 yılında 13,80 ile 57,30, tutan meyve adeti ise yılara göre sırasıyla ortalama 1,20 ile 4,00 ve 0,50 ile 1,60 arasında değişim göstermiştir. Meyve tutum oranları incelendiğinde ise en yüksek meyve tutum oranı 2021 yılında 11 nolu genotipte % 17,47 olarak belirlenirken, en düşük meyve tutum oranı ise 2022 yılında 28 nolu genotipte % 1,05 olarak tespit edilmiştir. Elde edilen sonuçlar doğrultusunda meyve tutum oranı yüksek olarak belirlenen genotiplerin, ayrıntılı fenolojik ve pomolojik analizlerinin değerlendirilerek yörede kullanımının arttırılabileceği düşünülmektedir.

The plum (Prunus cerasifera Ehrh) has been used worldwide both as a genetic source for breeding new rootstocks and as clonal rootstock for many Prunus species. Considering situations where wild relatives of plums are endangered, in-depth characterization of rootstock traits of genetic diversity of plum germplasm of Turkey with many ecogeographical locations is crucial. In the present study, therefore, three steps were followed for the selection of rootstock candidates among the plum germplasm grown in the Middle Euphrates. This region is characterized by an extremely hot climate with extremely warm summers and very low precipitation in summers. Initially, 79 rootstock candidates were selected based on rootstocks traits, and Myrobalan 29C was also used for the control rootstock in all steps. Hardwood cuttings were taken from each rootstock candidate, and after the rooting process in rootstock candidates, 39 rootstock candidates outperforming other candidates were selected according to root characteristics. Based on rooting ability, forty rootstock candidates with the longest root length below 33.50 mm, root number below 3.00, and rooting cutting number below 30.00% were eliminated. The second step of the study focused on the dwarfing characteristics of 39 rootstock candidates, and 13 and Myrobalan 29C out of 39 rootstock candidates’ dwarfing traits showed value higher compared to the other 26 rootstock candidates. Results indicated that the vigor of rootstock candidates was usually found to be strong (26), intermediate (4), and weak (9). Moreover, 13 out of 39 rootstock candidates’ dwarfism trait was better than the other 26 rootstock candidates. In Step 3, some morphological, physiological, and molecular evaluations were conducted in 13 rootstock candidates and the Myrobalan 29C clone, and there were significant differences between both rootstock candidates and the parameters evaluated. PCA has also been indicated that the reference rootstock Myrobalan 29C was grouped with 63B62, 63B69, and 63B14. The highest genetic similarity was found between 63B11 and 63B16, as well as between 63B76 and 63B66, while the lowest genetic similarity was observed between 63B72 and 63B61 candidates. Overall, the findings presented here provide valuable information about the level of rootstock candidates that could potentially be superior among previously uncharacterized plum cultivars in this plum-growing region of Turkey.