Turkish Hazelnut Research Articles

Effect of Tree Density on Yield and Fruit Quality of the Grafted Hazelnut Cultivar 'Tonda Francescana®'.

Optimizing planting density is crucial for balancing resource competition, light penetration, and tree productivity in orchard systems. This study investigateed the impact of planting density on the yield and fruit quality of the hazelnut cultivar 'Tonda Francescana®' grafted onto Corylus colurna L. rootstocks. The research aimed to assess how different planting densities influenced light penetration, canopy volume, yield, and the nutritional profile of hazelnuts during their sixth growing season. Three planting densities were tested: 625, 1250, and 2500 trees per hectare (low, medium, and high density, respectively). The results show that medium-density planting provided the best balance between light availability, canopy development, and yield efficiency. The synthesis of monounsaturated fatty acids (MUFA) and α-tocopherol (vitamin E) was more prominent in the medium-density system (80.2% and 10.3%, respectively), suggesting a favorable metabolic response to moderate competition for resources. In contrast, high-density planting yielded the most per hectare (2898 kg/ha) but exhibited lower individual tree productivity (1.16 kg). Low-density planting had the highest light penetration (53%) but lower overall yield (822 kg/ha) and quality, with greater starch accumulation in the fruit. In general, medium-density planting optimized both yield and kernel quality, with potential implications for orchard management and breeding strategies to enhance hazelnut production and nutritional value.

Comparison of Fruit Quality Characteristics of Çakıldak, Palaz and Tombul Hazelnut (Corylus colurna L.) Varieties Grown at Different Altitudes of Ordu Province

The hazelnut, which is known to be among the homelands of Anatolia, has been grown in our country for centuries. Hazelnut cultivation in Turkey dates back to ancient times. In the province of Ordu, the hazelnut varieties Çakıldak, Palaz and Tombul are mainly cultivated but other varieties are also grown. This study was carried out between 2022-2023 to determine the effects of altitude and location difference on the fruit characteristics of hazelnut varieties Çakıldak, Palaz and Tombul grown in Fatsa (300 m), İkizce (590 m) and Kumru (400 m) districts of Ordu province. In the study, the lowest average values for nut and kernel fruit weight, nut and shell thickness and kernel size were obtained from trees at 400 m altitude, while the highest values were obtained from trees at 590 m altitude. According to the results, the altitude had a different effect on the weight of the nuts and kernels depending on the variety. While the weight of nuts and kernels increased with increasing altitude in Çakıldak and Palaz varieties, these values decreased in Tombul variety. As a result some fruit quality characteristics of hazelnut varieties grown at different altitudes in Ordu province were found to be different.

Inducing Effect of Corylus avellana on Cytotoxic Activity in Lung and Breast Cancer Cells via Apoptosis

Turkish hazelnut (Corylus avellana L. cv Tombul) is a widely used nut in the chocolate industry and is also rich in polyphenol content, which promises anticancer effects. The anti-cancer and apoptotic effects of hazelnut leaves extracts examined on lung and breast cancer cells. Sulforhodamine B (SRB) and Adenosine 5’- triphosphate (ATP) assays were carried out for cell viability measurement. The mode of cell death was shown morphologically by the double fluorescence staining. Apoptosis was determined by performing caspase-mediated cytokeratin 18 (M30 ELISA) and western blot analysis. PARP, caspase 3, caspase 8, DR4, and GAPHD (Glyceraldehyde-3-phosphate Dehydrogenase) protein bands were visualized as markers of apoptosis. A wound healing test was employed to measure cell migration. Methanol extract of hazelnut leaf exhibited inhibition of cell growth activities in a dose-dependent manner. IC50 values were determined as 32.17 µg/ml in MCF-7, 32.16 µg/ml in MDA-MB-231, 20.40 µg/ml in A549 and 12.04 µg/ml in H1299 cells for ethanol extract while it was determined as 21.08 µg/ml in MCF-7, 40.16 µg/ml in MDA-MB-231, 22.04 µg/ml in A549 and 5.91 µg/ml in H1299 cells in methanol extract. In comparison, methanol leaf extracts were more effective in H1299 cells (IC50 value was 5.91 µg/ml).In comparison, ethanol leaf extracts were more effective in H1299 cells (IC50 value was 9.722 µg/ml). Western blot analysis demonstrated that hazelnut leaf extract treatment of cancer cells led to cell death via apoptosis and inhibited cell migration in lung and breast cancer cell lines. The cytotoxic effects of hazelnut extract on breast and lung cancer cells might be valuable and promising in elucidating cell death mechanisms for the development of new methods in cancer treatment.

Classification and Status by Geological Periods Relicts, Rare Species of Zakatala and Belokan Districts

The article provides data on period III relicts and rare tree and shrub species common in the forest ecosystems of the Zakatala and Belokan districts of Azerbaijan, and their classification and status by geological periods is given. As a result of research and analysis, the species Taxus baccata L., Hedera pastuchovii Woronow ex Woronow and Smilax excelsa L. were included in the relicts of the Poltava flora. In the forest ecosystems of the study areas, 6 tree and shrub relict species belonging to 6 families and 6 genera of the subtropical evergreen Poltava flora (mesothermal relicts of the Arctic flora of the III period) were identified: Taxus baccata L., Platanus orientalis L., Punica granatum L., Hedera pastuchovii Woronow ex Woronow, Smilax excelsa L. and Diospyros lotus L. With the exception of Smilax excelsa L., other 5 species are listed in the Red Book of the Azerbaijan Republic. In the Zakatala and Belokan districts, relict tree and shrub plants belonging to 15 families, 23 genera and 30 species of Arctic and deciduous Turgai flora (mesothermal relicts of the Arctic flora of the III period) are widespread. Of these, 10 species (Pinus kochiana Klotzsch ex K. Koch = Pinus sylvestris var. hamata Steven, Fraxinus coriariifolia Scheele, Castanea sativa Mill., Quercus iberica Steven ex M. Bieb., Pterocarya pterocarpa (Michx.) Kunth ex Iljinsk., Juglans regia L., Acer pseudoplatanus L., Acer hyrcanum Fisch. ex C. A. Mey., Corylus colurna L., Vitis vinifera L., are considered rare plants of Azerbaijan. It was established that 38 rare tree and shrub species belonging to 35 there are 23 families.

The impact and control of Brown marmorated stink bugs on Turkish hazelnut production

The Turkish hazelnut is a crucial commodity both in Turkey and globally, with Turkey accounting for approximately 70% of the world's hazelnut production. However, hazelnut harvesting faces significant challenges, one of which is the presence of stink bug pests such as the brown marmorated stink bug (BMSB). This study utilized a mathematical model to examine the adverse impact of pests such as the brown marmorated stink bug [Halyomorpha halys (Stål, 1855) (Hemiptera: Pentatomidae)] and similar stink bug pests on hazelnut production. The findings revealed that between 2017 and 2022, hazelnut yields in Turkey suffered damage from stink bug pests like the brown marmorated stink bug, amounting to 106,820 tonnes annually and 640,920 tonnes cumulatively. Furthermore, this study demonstrated that the application of control measures, whether through biocontrols, traps, or chemicals, to increase the death rate of BMSB-type pests by 25% or 50%, or to decrease the egg ratio by 25% or 50%, has the potential to save up to 82,506 tonnes of hazelnut production from these pests annually. Overall, this study highlights the importance of managing pest infestations in agricultural production and the potential benefits of using control methods to mitigate their impact.

Molecular characterization of Turkish hazelnut cultivars and genotypes using SSR markers

This study defines the genetic characterization of 16 hazelnut varieties and 64 genotypes. SSR method was used in molecular characterization studies. 18 SSR primers were used. In the SSR method, 118 bands were obtained, and 115 were polymorphic. The similarity coefficient in overall genotypes were between 0.12 and 0.98 in SSR andthe polymorphism rate of the primer pairs used was calculated as 98.0%. The lowest polymorphism information content value (0.542) was obtained from the CAC- C 028 locus, and the highest polymorphism information content value (0.987) was obtained from the CAC- B 113 locus. The average polymorphism information content value was 0.786. The total discrimination power values of SSR loci were determined as 17.98; the lowest (0.748) discrimination power value was obtained from the CAC- B 020 locus, while the highest (1.404) discrimination power value was obtained from the CAC- A 024 b locus. The genotypes’clustering positions across the dendograms were essentially correlated with their geographic origins. This result shows that genetic origin plays an important role in terms of classification of genotypes in hazelnut.

Microservices‐based databank for Turkish hazelnut cultivars using IoT and semantic web technologies

SummaryInformation and communication technologies (ICTs) can play a crucial role in facilitating access to comprehensive information on the quality standards of Turkish hazelnut cultivars. In this regard, this study introduces a Hazelnut Databank System (HDS) that utilizes the microservices architecture, an integrated software system supported by the Internet of Things (IoT) and semantic web, to categorize Turkish hazelnut cultivars. The study focuses on developing microservices using various programming languages and frameworks. Specifically, C# on the .NET Core Framework was used for both microservices and the web‐based application implemented through the ASP.NET Core MVC Framework. Mobile‐based software applications were created using Xamarin. Forms, and the IoT application was developed using the Python programming language. The data storage is facilitated through the MS SQL Server database. Additionally, the study incorporates the implementation of a hazelnut species classification system using the DNN + ResNet50 machine learning model, achieving an impressive accuracy rate of 95.77%. The overall usability of the system was evaluated, resulting in a score of 42 out of 50. By providing detailed information on Turkish hazelnut cultivars, the HDS has the potential to greatly improve hazelnut production quality in Turkey and increase awareness of hazelnut agriculture among relevant stakeholders.

Analysis of Anticancer Taxanes in Turkish Hazelnut (Corylus avellana L.) Genotypes Using High-Performance Liquid Chromatography.

This study aimed to investigate the anticancer taxane profiles of edible and non-edible parts of seven Turkish hazelnut (Corylus avellana L.) genotypes. Hazelnut is one of the healthy foods rich in nutrients and antioxidants. Its regular consumption is associated with a reduced risk of coronary heart disease and cancer. Hazelnut has been described as a plant source that produces taxanes which are widely used in many cancers. Türkiye is a homeland of hazelnut culture and has its own cultivars. Investigation of anticancer taxane profiles in different parts of Turkish hazelnut genotypes is important to show the potential and value of this plant from the perspective of the pharmaceutical and food industries. In this study, green leafy covers (GLCs) and hard shells (HSs) (non-edible parts), skinless kernels (SKs), brown-skins (BSs), and brown-skinned kernels (BSKs) (edible parts) of Çakıldak, Sivri, Tombul, Palaz, and Kalınkara as standard and Ham and Sivri Yağlı as local genotypes were used. The five parts of each genotype were ground to powder and eliminated to a size of less than 80 mesh. Each part was extracted using hexane and methanol for 10-deacetylbaccatin III (10-DAB III), baccatin III (BAC III), cephalomannine, and paclitaxel analyses in three replicates. Samples and standards were analyzed by acetonitrile: water gradient method on NOVA Spher 100 Phenyl-Hexyl C18 column inhigh-performance liquid chromatography reverse phase system with 228 nm ultraviolet detector and 1.0 mL/min flow rate. Microsoft Office Excel, 2016, and analysis of variance Jamovi Version 2.3 were used for statistical and data analysis, consecutively. Hazelnut parts differed to a very high degree from each other in terms of the highest amount of 10- DAB III (Ham HSs, 9,15 μg/g), BAC III (Kalınkara BSs, 7.24 μg/g), cephalomannine (Sivri Yağlı BSs, 6.37 μg/g), and paclitaxel (Ham BSKs, 4.36 μg/g) they contained. While HSs, BSKs, and BSs were rich in taxanes in all of the analyzed genotypes, SKs, and GLCs remain limited for anticancer taxanes. This is the first report that revealed the differences in taxane contents of Turkish hazelnuts including previously untested standard and local genotypes and their parts. Significant differences between genotype and hazelnut parts are expected to highlight the health benefits of consuming raw Turkish hazelnut with BSs and their possible use as a functional food. These results add more information to elucidate the bioactive potential of Turkish hazelnuts and their by-products and provide a promising resource for the food and pharmaceutical industry with an anticancer perspective.

Savurmalı Fındık Kırma Makinesinde Dönme Hızının Enerji Tüketimi, Kırma Verimi ve İç Fındık Kalitesi Üzerine Etkilerinin Belirlenmesi

In this study, the effects of different hazelnut varieties and impeller velocities on energy consumption, hazelnut cracking efficiency and kernel quality in the centrifugal hazelnut cracking method were examined. Giresun Quality Tombul, Levant Quality Çakıldak and Kara hazelnuts, which are important Turkish hazelnut varieties, were selected as the study material. A centrifugal type machine, which does not require grading, crackes with the help of a rotating impeller, and has a crushing capacity of 100 kg per hour, was used as the experimental device. The study was carried out at 4 different fan rotation speeds: 350, 750, 1100 and 1450 rpm. According to the study results, although it is resulted that each hazelnut varieties different behaviors at different impeller velocities, it can be said that the optimum benefit is achieved at 1100 rpm. The results of the article emphasize that equipment adjustments and the development of hazelnut variety-specific processing strategies are important in optimizing cracking and parted rates in the hazelnut processing process. This study can serve as a basis for studies aimed at contributing to efficiency and quality improvements in the hazelnut processing industry.

The Leaf Properties, Stomatal Index and Chlorophyll Content of Turkish Hazelnut (Corylus avellana L.) Cultivars

In the present study, leaf micromorphlogical properties, stoma indexs and chlorophll contents of 20 Turkish hazelnut (Corylus avellana) cultivars were studied. Investigated cultivars were “Acı, Allahverdi, Cavcava, Çakıldak, Foşa, Giresun melezi, Incekara, Kalınkara, Kan, Karafındık, Kargalak, Kuş, Mincane, Okay 28, Palaz, Sivri, Uzunmusa, Tombul, Yassı Badem, Yuvarlak Badem”. Three wax ornamentation types are recognized; crust, smooth and granules. Epidermal features, stomatal index and chlorophyll amounts showed some differences between C. avellana cultivars. Stoma width and stoma length were determined to be important for Palaz, Kuş, Yuvarlak Badem ve Yassı Badem cultivars. Stoma index, upper epidermis and lower epidermis width, upper epidermis and lower epidermis length values were determined to be distinctive for Allahverdi, Kargalak, Kara and Mincane. Chlorophyll density was found to be distinctive for Sivri, Çakıldak, İncekara and Acı cultivars The highest similarity was found between Okay 28 and Tombul cultivars with a rate of 0.98. The lowest similarity was found between Sivri-Karafındık, Sivri-Foşa and Sivri-Kargalak with 0.87.

Morphometric Diversity for Rootstock Characteristics of Turkish Hazel (Corylus colurna L.) Populations in The Western Black Sea Region of Türkiye

The Turkish hazel (Corylus colurna L.) is native to Türkiye, where it is found only in small, scattered, and isolated populations within its natural distribution area. These remaining populations are of critical importance for conservation, for continued use as a natural reservoir, and natural selection. The trees are up to 400 years old and already well-adapted to harsh environmental conditions. In recent years, this species has drawn the attention of agriculture and forest practitioners and scientists in several countries who use this important and valuable tree species in studies of the effects of climate change. The origin and genotype of the reproductive material of this species play a key role in its adaptation to environmental conditions, and possible cultivation. The purpose of this study is to reveal the variation of genotypes selected from 13 different populations in Kastamonu and Bolu provinces in terms of rootstock characteristics. These regions are the locations where the Turkish tree hazel is most abundant. For this aim, the growth habit, vigor, number of suckers, and internode of one-year-old shoots were scored on the parent trees. A Kruskal Wallis-H test was applied to the non-parametric data to determine if there were differences among the populations for each variable and the total number of points. Then the Mann-Whitney-U test was used for differences among the groups. In addition, the phylogenetic relationship among the populations and genotypes was revealed by Cluster analysis. Among the rootstocks scored, KTU3 and KTU64 provided the highest score according to non-suckering and strong growth. It has been observed that individuals in Turkish hazelnut populations generally do not form suckers (%89.4) and show strong growth. C. colurna trees were observed to be individual and scattered in the population. Most of the trees are elderly and need to be protected in situ. Turkish hazel population will play a key role in production and sustainable such as to develop rootstock and variety in agriculture production, sustainable forest development, and for ecological adaptation in climate change scenarios.

Accumulation and transfer of P and K, macronutrient elements for plants, in Corylus colurna L. stem sections

One of the most essential factors in plant development is the nutrient content in the soil. Phosphorus (P) and potassium (K), essential macronutrients in plant nutrition, are vital in plant growth and development. Therefore, although many studies have been conducted on these elements in agricultural plants, the number of studies on forest trees could be much higher. In particular, there needs to be more information about the accumulation and transfer of these elements in different plant tissues. This study examined the change and transfer of P and K concentrations in the Corylus colurna tree's trunk parts. Within the scope of the study, the differences in P and K concentrations in the Corylus colurna trunk were examined based on organ, direction, and period. As a result, the most elevated concentrations of both elements were in the barks; the difference in direction was not evident in the wood, and both elements could be transferred within the wood.

Çakıldak Fındık Çeşidinin Corylus colurna L. Çöğür Anacı Üzerinde İlkbahar ve Yaz Döneminde Aşıyla Çoğaltılması

Objective: The objective of this study was to determine the grafting success of hazelnut on Corylus colurna L. seedling rootstock in the spring and summer periods in Ünye, Ordu.
 Materials and Methods: The rootstock material was 2-3 years old Corylus colurna L. seedlings. The scion was Çakıldak (Corylus avellana L.) cultivar. For three years (2020-2022) in the spring, whip grafting on five different dates (4 April, 11 April, 18 April, 25 April and 2 May) and patch budding on three different dates (2 May, 9 May and 16 May) were applied under unheated high plastic tunnel conditions. Daily fresh scions and stored scions (SS) at 4°C were used for whip grafting. For two years (2020 and 2021), Corylus colurna L. seedlings were grafted with patch budding technique on 3 different dates (August 6, August 13 and August 20) under open field conditions. Graftings and buddings were made directly on the tubed seedlings.
 Results: The success and shoot development in whip grafting and patch budding in the spring were significantly affected by grafting dates over three years. Whip graftings gave the most successful results using SS on April 4 (93.3%) and April 11 (86.6-93.3%) in 2020 and 2022. They developed shoots between 171.8 cm and 212.2 cm depending on year, grafting date and scion type. Patch buddings in the spring gave in the most successful results on 16 May 2020 (93.3%) and 16 May 2022 (83.3%). They developed shoots between 150 cm and 218, depending on year and grafting date. Patch buddings in summer resulted in the highest success on 20 August 2020 (93.6%) and 20 August 2021 (80%). Their shoot developments were between 206 cm and 228, depending on year and grafting date.
 Conclusion: As a result, successful results were obtained from grafting trials of Çakıldak hazelnut cultivar on Corylus colurna L. rootstock in the spring and summer periods under Ünye ecological conditions. It has been evaluated that the data will contribute to the establishment of the hazelnut nursery sector and will shed light on future research.

The Effect of Rootstock/Variety Combinations on Plant Development in Some Hazelnut Varieties Grafted on Turkish Hazelnut (Corylus colurna L.) Rootstock

Amaç: Bu araştırma Tombul, Palaz, Çakıldak ve Okay 28 fındık çeşitlerinin bitki gelişimleri üzerine Türk fındığı (Corylus colurna L.) anacının etkisini belirlemek amacıyla yürütülmüştür.
 Materyal ve Yöntem: Fındık Araştırma Enstitüsü Müdürlüğü’nde 2019 yılında tesis edilen bahçede yürütülen bu çalışmada, Türk Fındığı anacı üzerine dilcikli aşı metodu ile aşılanan Tombul, Palaz, Çakıldak ve Okay 28 fındık çeşidi bitkilerinde, bitki boy ve çap gelişimleri ile dip sürgünü verme eğilimleri üç yıl süreyle (2020-2022) takip edilmiştir.
 Araştırma Bulguları: Araştırma bahçesindeki çeşit/anaç kombinasyonlarında bitkilerin boyları 113.3 cm (2020 yılı) ile 173.3 cm (2022 yılı) arasında değişiklik göstermiştir. Çeşitler arasındaki boy artışı değerlerinde, istatistiki açıdan önemli bir farklılık ortaya çıkmamış olsa da ortalama 142.0 cm ile en yüksek bitki boyu Okay 28 çeşidinin bitkilerinde kaydedilmiştir. Corylus colurna L. anacı üzerine aşılı 4 fındık çeşidinin de 2020, 2021 ve 2022 yıllarında dip sürgünü oluşturmadığı görülmüştür. Aşılı bitkilerde anaç, aşı noktası ve kalem çapındaki gelişme durumlarının farklılıkları sadece yıllar arasında istatistiksel olarak önemli çıkmıştır. İstatistiki açıdan önemli bulunmasa da, araştırma bahçesindeki bitkilerin kalem çapındaki artış en fazla 2022 yılında Okay 28 bitkilerinde (21.2 mm) gerçekleşmiştir. Bunu Tombul (21 mm), Palaz (18.9 mm) ve Çakıldak (18.2 mm) çeşitlerine ait aşılı bitkiler takip etmiştir. 2022 yılında yine istatistiksel olarak önemli çıkmasa da C. colurna/Okay 28 kombinasyonu olan bitkilerde aşı noktası çapı ortalama 35.7 mm ile diğer kombinasyonlara göre daha yüksek bulunmuştur. Araştırma bahçesinde, bitkilerin ilk meyvelerini 2020 yılında vermeye başladığı görülmüştür.
 Sonuç: Deneme süresince aşılı fındık bitkilerinde boy gelişimi açısından istatistiki bir farklılık belirlenmemiş olsa da çeşit özelliklerinin bitki gelişimine etkisinin olduğu düşünülmektedir. Ayrıca, Corylus colurna L. anacı üzerine aşılı tüm çeşitlerin dip sürgünü oluşturmaması ve aşılı bitkilerin üç yaşındayken meyve vermeye başlaması çalışmanın olumlu sonuçlarındandır.

Optimization and Antifungal Activity of Silver Nanoparticles Synthesized Using the Leaf Extract of Corylus colurna L. (Turkish hazelnut)

Amaç: Bu çalışma, yüz merkezli merkezi kompozit tasarım (FCCCD)’a dayalı yanıt yüzey yöntemi (RSM) ile Corylus colurna yaprak ekstraktı kullanılarak mikrodalgada sentez edilen gümüş nanopartiküllerin (AgNP’lerin) üretimini optimize etmeyi, sentezlenen nanopartikülleri çeşitli spektroskopik ve mikroskobik yöntemlerle karakterize etmeyi ve bazı Phytophthora türleri üzerindeki antifungal etkilerini değerlendirmeyi amaçlamaktadır.
 Materyal ve Yöntem: Çalışmada, yanıt yüzey yönteminin FCCCD’i, 350-420 nm spektral dalga aralığında maksimum AgNP miktarını elde etmek için üç farklı sentez değişkeni (AgNO3 konsantrasyonu, fındık yaprak ekstraktı/AgNO3 oranı ve reaksiyon süresi)’nin birleşik etkisini araştırmak için kullanılmıştır. Spektral eğri altındaki tahmini alan basit bir orta nokta kuralı kullanılarak Microsoft Office Excel programı yardımı ile hesaplanmıştır. Optimum koşullar altında sentezlenen fındık yaprak ekstraktı-AgNP’leri karakterize etmek için Ultraviyole Görünür (UV-Vis) Spektroskopisi, Fourier Dönüşümlü Kızılötesi (FT-IR) Spektroskopisi ve Transmisyon Elektron Mikroskobu (TEM) kullanılmıştır. AgNP’lerin antifungal etkinliği, altı Phytophthora türü (P. cactorum, P. capsici, P. cinnamomi, P. citrophthora, P. nicotianae ve P. palmivora)’ne karşı in vitro koşullarda denenmiş olup, deneme 6 tekerrürlü olarak yürütülmüştür.
 Araştırma Bulguları: UV-Vis spektroskopisi, farklı koşullar altında sentezlenen AgNP’lerin tipik yüzey plazmon rezonans değerlerinin 396 ile 411 nm dalga boyu aralığında değiştiğini ortaya koymuştur. AgNO3 konsantrasyonu, bitki yaprak ekstraktı/AgNO3 oranı ve reaksiyon süresi sırasıyla 5 mM, 0.1 ve 90 saniye olduğunda, araştırılan aralıkta optimum AgNP üretimi elde edilmiştir. FT-IR spektrumu, AgNP’lerin O–H, N–H, C=C, C–N ve C–O gruplarını içerdiğini ve fındık yaprak ekstraktındaki çeşitli bileşiklerin AgNP’lerin sentezinde önemli bir rol oynadığını göstermiştir. TEM analiz sonuçları, AgNP’lerin ortalama 17.48 nm (Gauss uyumu) büyüklüğe sahip küresel formda olduğunu ortaya koymuştur. Yeşil sentezlenen AgNP’lerin P. cactorum, P. capsici, P. cinnamomi, P. citrophthora, P. palmivora ve P. nicotianae’nın misel gelişimini sırasıyla %81.67, %74.80, %73.54, %81.01, %74.50 ve %62.39’a kadar azaltmıştır. Ayrıca AgNP’lerin EC50 değerlerinin 118.58-292.56 µg ml-1 arasında değiştiği ve MIC değerlerinin ise 340 µg ml-1’in üzerinde olduğu belirlenmiştir.
 Sonuç: Bu çalışma, fındık yaprak ekstraktı ile sentezlenen AgNP’lerin, Phytophthora türlerinin neden olduğu hastalıkların mücadelesinde kullanılmak üzere daha fazla araştırılması gerektiğini önermektedir.

First insights into genetic structure and diversity of Corylus colurna L. for conservation of its genetic resources and possible assisted migration

Climate change is already affecting all forest ecosystems and threatening species therein. By establishing mixed forests incorporating other tree species (e. g. scattered broadleaves) adaptation of forest stands to changing environmental conditions can be improved and the risks minimized. Turkish hazel (Corylus colurna L.) has been currently discussed as a valuable so-called alternative tree species in some European regions because it is well adapted to difficult environmental conditions. However, in its natural distribution area Turkish hazel has been overexploited because of its valuable wood and can only be found in small and isolated populations. Therefore, we examined the genetic structure and variation of Turkish hazel covering most of its natural distribution range in Asia Minor, the Caucasus, and the Balkan Peninsula. Altogether, 689 Turkish hazel trees from 25 populations were analysed at 15 nuclear and five chloroplast microsatellite markers. Both data sets revealed distinct genetic clusters of Turkish hazel in its natural distribution range, suggesting separate refugia and migration pathways during the Holocene. Medium to high level genetic variation was found, with somewhat lower values in Georgia and Turkey compared to the Balkan populations. Overall, our results highlight the need to delineate provenance regions, identify gene conservation units (GCUs) and seed stands for Turkish hazel which are essential for species conservation, provenance research and possible assisted migration attempts. Based on our results each country is able now to start conservation programs and select GCUs for Turkish hazel.

Recycling of Hazelnut Husk; from Bio‐waste to Phyto‐Assisted Synthesis of Silver Nanoparticles

AbstractIn the present work, green synthesis is utilized in the synthesis of silver nanoparticles with hazelnut (Corylus Colurna) husk which is the outer leaf part of the hazelnut shell and is considered bio‐waste. According to transmission electron microscopy and x‐ray diffraction analysis, the morphology of the silver nanoparticles synthesized by 0.1 g/mL hazelnut husk extract is found to be spherical with an average diameter of 6.57 nm and possesses ultra‐narrow size distribution. UV‐visible spectrometry reveals the absorbance peak range between 450–475 nm which is in the range of surface plasmon resonance peak of silver nanoparticles with spherical morphology. Antibacterial properties of the synthesized silver nanoparticles were tested on E. coli and significant antimicrobial activity was found with up to 79 % areal inhibition efficiency. The research revealed that the hazelnut husk extract, a reducing agent used in syntheses with different mass concentrations of hazelnut husk extract, also affects the size of the nanoparticles, allowing for the possibility of controlling their size. The antibacterial properties of silver nanoparticles, synthesized in a spherical form of different sizes, correspondingly increased their effect on bacteria which is observed in the inhibition zone. The synthesis of silver nanoparticles, which can be used in many fields for agriculture, cosmetics, and medical purposes, using plant extract and minimal chemicals is crucial because it affects its toxicity. The synthesis of silver nanoparticles with hazelnut husk not only reduces the chemical waste and toxicity, but it is both easily accessible and helps the environment and sustainability by recycling a normally considered bio‐waste by‐product of high‐value‐added crop to a technologically valuable product silver. Moreover, synthesized silver nanoparticles could be an essential part of applications ranging from antibacterial surface treatments to drug delivery systems.

Propagation of Turkish hazelnut cultivars with softwood cuttings

Propagation of Turkish hazelnut cultivars with softwood cuttings

Protein content in pollen of Turkish hazelnut cultivars

Protein content in pollen of Turkish hazelnut cultivars

Proof of concept to characterize historical heavy-metal concentrations in atmosphere in North Turkey: determining the variations of Ni, Co, and Mn concentrations in 180-year-old Corylus colurna L. (Turkish hazelnut) annual rings

Proof of concept to characterize historical heavy-metal concentrations in atmosphere in North Turkey: determining the variations of Ni, Co, and Mn concentrations in 180-year-old Corylus colurna L. (Turkish hazelnut) annual rings