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− Plant-derived smoke has been shown to trigger germination of many Lamiaceae species growing in Mediterranean-type ecosystems. However, very little is known about the germination response of Lamiaceae species to smoke-derived compounds, such as karrikinolide (KAR1) and cyanohydrin. In this work, therefore, we aimed to ascertain the effects of smoke-derived compounds on seed germination in seven Mediterranean Lamiaceae species (Ballota acetabulosa, Lavandula stoechas subsp. stoechas, Origanum onites, Phlomis bourgaei, P. lycia, Stachys cretica subsp. smyrnaea, and Teucrium chamaedrys). To achieve this goal, seeds of study species were exposed to different concentrations of smoke-water, KAR1, mandelonitrile (MAN), and KAR1 + MAN. Seeds from treatment groups were then incubated at 20 °C in dark conditions, and germination counts were made twice weekly for 35 days. Our results show that smoke leads to a significant increase in germination percentage of B. acetabulosa, P. lycia, and S. cretica as compared to control conditions. KAR1 stimulated the germination of B. acetabulosa and S. cretica while MAN treatments did not promote the germination of Lamiaceae species. The combination of KAR1 and MAN not only induced the germination of three smoke-sensitive species but also notably increased the germination percentage of T. chamaedrys. In conclusion, our study supports the idea that smoke has a positive impact on the germination of Lamiaceae species and provides evidence that combined application of KAR1 and cyanohydrin is more effective in the stimulation of seed germination than the separate application of these two compounds., − Bitki kökenli dumanın, Akdeniz tipi ekosistemlerde yetişen birçok Lamiaceae türünün çimlenmesini tetiklediği gösterilmiştir. Bununla birlikte, Lamiaceae türlerinin karrikinolid (KAR1) ve siyanohidrin gibi duman kökenli bileşik-lere olan çimlenme tepkileri hakkında çok az şey bilinmektedir. Bu nedenle, bu çalışmada, duman bileşiklerin yedi Akdeniz Lamiaceae türünde (Ballota acetabulosa, Lavandula stoechas subsp. stoechas, Origanum onites, Phlomis bourgaei, P. lycia, Stachys cretica subsp. smyrnaea ve Teucrium chamaedrys) tohum çimlenmesi üzerindeki etkile-rini belirlemeyi amaçladık. Bu hedefe ulaşmak için çalışma türlerinin tohumları farklı konsantrasyonlarda duman-suyu, KAR1, mandelonitril (MAN) ve KAR1 + MAN’a maruz bırakılmıştır. Uygulama gruplarına ait tohumlar daha sonra karanlık koşullarda 20 °C'de inkübe edilmiş ve 35 gün boyunca haftada iki kez çimlenme sayımları yapıl-mıştır. Sonuçlarımız, dumanın kontrol koşullarına göre B. acetabulosa, P. lycia ve S. cretica'nın çimlenme yüzde-lerinde önemli bir artışa yol açtığını göstermektedir. KAR1, B. acetabulosa ve S. cretica'nın çimlenmesini uyarırken, MAN uygulamaları Lamiaceae türlerinin çimlenmesini teşvik etmemiştir. KAR1 ve MAN kombinasyonu dumana duyarlı üç türün çimlenmesini tetiklemekle kalmamış, aynı zamanda T. chamaedrys'in çimlenme yüzdesini de önemli ölçüde arttırmıştır. Sonuç olarak, çalışmamız, dumanın Lamiaceae türlerinin çimlenmesi üzerinde olumlu bir etkiye sahip olduğu fikrini desteklemekte ve KAR1 ve siyanohidrinin birlikte uygulanmasının, tohum çimlenme-sinin uyarılmasında, bu iki bileşiğin ayrı ayrı uygulanmasına göre daha etkili olduğuna dair kanıtlar sağlamaktadır

Yangın, bitki komünitelerinin kompozisyonunu ve dağılımını şekillendiren yaygın bir müdahale etmenidir. Birçok bitki türü, yangına eğilimli alanlardaki devamlılıklarını sürdürebilmek için tohum bekletme (serotinlik), yanıcılık, sürgün verme, yangınla uyarılan tohum çimlenmesi ve yangın sonrası çiçeklenme gibi bir takım adaptif özellikler geliştirmiştir. Dumanın tohum çimlenmesi üzerindeki pozitif etkisi, farklı ortamlarda yetişen birçok bitki türünde gösterilmiştir. Buna ek olarak, dumanın çeşitli bitkilerde fide büyümesini, somatik embriyogenezi ve polen çimlenmesini tetiklediği de tespit edilmiştir.Son yıllarda, duman maruziyetiyle ilişkili biyokimyasal ve moleküler değişiklikleri belirlemek için çok sayıda çalışma yapılmıştır. Bununla birlikte, duman ve duman kökenli bileşiklerin (örneğin, karrikinolid (KAR1) ve siyanohidrin) çimlenme ve fide büyümesi üzerindeki etki mekanizmaları hakkında hala sınırlı bilgi bulunmaktadır. Bu tez kapsamında, bitkilerde duman, KAR1 ve siyanohidrin ile ilişkili yanıtlara daha fazla ışık tutmak için üç çalışma gerçekleştirilmiştir.İlk çalışmada, Akdeniz havzasında yetişen 37 türün çimlenmeleri ve fide büyümeleri üzerine duman çözeltisi, KAR1, mandelonitril (bir siyanohidrin analoğu), potasyum nitrat ve giberellik asidin etkileri test edilmiştir. Sonuçlarımız, 21 türde çimlenmenin ve/veya fide büyümesinin yangınla ilişkili en az bir uygulama tarafından tetiklendiğini göstermiştir. Ayrıca yangın kökenli bileşiklerin, sürgün büyümesine kıyasla kök büyümesini uyarmada daha etkili oldukları tespit edilmiştir.İkinci çalışmada, farklı duman ön uygulamalarına tabi tutulan mısır tohumları ile bir fide büyüme deneyi gerçekleştirilmiş ve mısır kök örneklerinin metabolik profilleri 1H nükleer manyetik rezonans (NMR) spektroskopisi kullanılarak belirlenmiştir. NMR spektrumlarından, farklı kimyasal gruplara ait toplam 29 metabolit tanımlanmıştır. Bu 29 metabolitten 20'sinin konsantrasyonu, en az bir duman ön uygulaması sonrasında kontrole göre anlamlı olarak (p < 0.05) değişmiştir. Ayrıca fonksiyonel analizlerin sonuçları, duman ön uygulamalarının galaktoz metabolizması, glikoliz, glioksilat metabolizması, TCA döngüsü ve nişasta/sükroz metabolizması gibi karbonhidrat ve enerji ile ilişkili metabolik yolları belirgin olarak etkilediğini göstermiştir.Üçüncü çalışmada, bor toksisitesi altındaki buğday fidelerinde, duman çözeltisi ve KAR1'in büyüme ve oksidatif stres üzerine etkileri incelenmiştir. Sonuçlarımız, KAR1 ve duman uygulamalarının, kök ve sürgün dokularındaki bor birikimini azaltarak, kök büyümesini arttırdıklarını ve oksidatif hasarı hafiflettiklerini ortaya koymuştur.Bir bütün olarak ele alındığında, bu tezin bulguları, duman ve duman kökenli bileşiklerin (i) birçok Akdeniz bitkisinde çimlenme ve fide büyümesini uyardıklarını, (ii) karbonhidrat ve enerji ile ilişkili metabolik yolları etkilediklerini ve (iii) buğday fidelerinin bor stresine olan toleransını arttırdıklarını göstermiştir. Fire is a common disturbance agent that has shaped the composition and distribution of plant communities. Many plant species have evolved adaptive traits such as serotiny, flammability, resprouting, fire-stimulated germination and post-fire flowering to persist in fire-prone areas. The positive effect of smoke on seed germination has been shown in many plant species grown in different environments. In addition to this, it has also been determined that smoke triggers seedling growth, somatic embryogenesis and pollen germination in various plants. In recent years, a quite number of studies have been conducted to determine the biochemical and molecular alterations associated with smoke exposure. However, there is still limited knowledge concerning the modes of action of smoke and smoke-derived compounds (e.g. karrikinolide (KAR1) and cyanohydrin) on germination and seedling growth. Within the scope of this thesis, three studies were carried out in order to shed more light on smoke, KAR1, and cyanohydrin related responses in plants.In the first study, the effects of the smoke solution, KAR1, mandelonitrile (a cyanohydrin analog), potassium nitrate and gibberellic acid on the germination and seedling growth of 37 species from the Mediterranean Basin were tested. Our results showed that germination and/or seedling growth in 21 species were triggered by at least one of the fire-related treatments. Moreover, it was found that fire-derived compounds were more effective in stimulating root growth than shoot growth.In the second study, a seedling growth experiment was performed with maize seeds subjected to different smoke pre-treatments and the metabolic profiles of maize root samples were determined using 1H nuclear magnetic resonance (NMR) spectroscopy. A total of 29 metabolites belonging to various chemical groups were identified from NMR spectra. Concentrations of 20 out of these 29 metabolites displayed significant (p < 0.05) changes after at least one smoke pre-treatment compared to control. Furthermore, the results of functional analyses demonstrated that smoke pre-treatments markedly affected the carbohydrate- and energy-related metabolic pathways, such as galactose metabolism, glycolysis, glyoxylate metabolism, TCA cycle, and starch/sucrose metabolism. In the third study, the effects of the smoke solution and KAR1 on growth and oxidative stress in wheat seedlings under boron toxicity were examined. Our results revealed that KAR1 and smoke treatments enhanced the root growth and alleviated the oxidative damage by decreasing boron accumulation in root and shoot tissues.Taken as a whole, the findings of this thesis suggested that smoke and smoke-derived compounds (i) stimulated the germination and seedling growth in many Mediterranean plants, (ii) affected the carbohydrate- and energy-related metabolic pathways and (iii) enhanced the tolerance of wheat seedlings to boron stress. 137

Bu tezde, Cistus salviifolius L.?un (Cistaceae) yangın sonrası çimlenme özellikleri araştırılmıştır. Çalışma, Marmaris yöresinde yanmış bir alan içinde bulunan, büyük bir popülasyon ile gerçekleştirilmiştir. Seksen bireye ait meyveler 8 alt popülasyondan toplanmıştır. Ayrıca, bitki boyu, yaprak boyutu, bir meyvedeki ortalama tohum sayısı, ortalama tohum ağırlığı ve tohum su geçirgenliği gibi önemli bitki özellikleri her bir birey için belirlenmiştir. Deneylerde, C. salviifolius? un tohum çimlenmesi üzerine yangınla ilgili imlerin (sıcaklık şoku ve duman) etkileri bireysel ve alt popülasyon düzeyinde incelenmiştir. Bitki özellikleri ve çimlenme sonuçları arasındaki ilişkiler de bir korelasyon matrisi ile saptanmıştır. Deneylerin sonuçları, C. salviifolius?da çimlenmenin başlıca sıcaklık şokuuygulamalarıyla uyarıldığını göstermiştir. Ayrıca, sıcaklık şoku ve dumanın kombine etkisi ilgili kontrol ile karşılaştırıldığında, bazı bireylerin çimlenme yüzdesini arttırmıştır. Ancak, dumanın bağımsız etkisi herhangi bir bireyin çimlenmesini uyarmamıştır. Korelasyon matrisi, tohum su geçirgenliği, meyve sayısı, tohum büyüklüğü ve bir meyvedeki ortalama tohum sayısının çimlenme başarısını etkilediğini göstermiştir. Bu çalışma, öngörülemeyen çevre koşullarında (örneğin; kuraklık ve yangın durumu) çimlenmeyi etkileyen faktörlerin daha iyi anlaşılmasına katkıda bulunabilir.Anahtar Kelimeler: Cistus salviifolius, Yangın, Tohum çimlenmesi, Sıcaklık şoku, Duman, Adaçayı yapraklı laden In this thesis, post-fire germination properties of Cistus salviifolius L. (Cistaceae) were investigated. The study was conducted with a large population located within a burned area in Marmaris region. Fruits of 80 individuals were collected from 8 metapopulations. Also, important plant traits such as plant height, leaf size, mean number of seeds per fruit, mean seed weight and water-permeability of seeds weredetermined for each individual. In experiments, effects of fire-related cues (thermal shock and smoke) on seed germination of C. salviifolius were examined at individual and metapopulation levels. Relationships between plant traits and germination results were also determined by a correlation matrix.The results of the experiments were demonstrated that germination of C. salviifoliuswas mainly stimulated by thermal shock treatments. Also, combined effects of thermal shock and smoke enhanced the germination percentage of some individualscompared to corresponding control. However, independent effect of smoke did not induce the germination of any individuals. Correlation matrix was indicated that water-permeability of seed, fruit number, seed size and mean number of seeds per fruit were affected the germination success.This present study can contribute to better understanding of the factors that affect germination in unpredictable environmental conditions (e.g., drought and fire event).Keywords: Cistus salviifolius, Fire, Seed germination, Thermal shock, Smoke, Sageleaf rockrose 78

There is considerable intra-and interspecific variation in boron (B) toxicity tolerance in crop plants. In this study, we aimed to investigate the mechanisms involved in tolerance to excess B in barley (Hordeum vulgare) in the early stages of plant development. To do this, B-sensitive (B?lb?l-89) and B-tolerant (Tarm-92) barley cultivars were grown hydroponically under control and B stress conditions (10 mM H3BO3) for 4 or 7 days. The hydrogen peroxide (H2O2), malondialdehyde (MDA), total phenolic, total flavonoid, anthocyanin, proline, and total sugar contents, as well as DPPH radical scavenging capacity, were then determined for both cultivars. Our results showed that B treatment led to significant increases in the B concentration of the barley cultivars for both exposure times. However, there were no drastic differences in the B concentration of the roots and shoots between the sensitive and tolerant cultivars. While the dry root weight of B?lb?l-89 was reduced after 7 days of B stress (p < 0.05), such a decrease was not observed in Tarm-92. The H2O2, MDA, proline, total sugar, and anthocyanin contents of both cultivars increased considerably in response to excess B during at least one treatment period (p < 0.05). The H2O2 content of Tarm-92 under control and B stress conditions was significantly greater than that of B?lb?l-89, but there was no difference in the MDA content and radical scavenging capacity between the two cultivars. Finally, a 35% increase was found in the total flavonoid content of the Tarm-92 seedlings exposed to B stress for 4 days. In conclusion, the findings of this study suggest that tolerance to B toxicity in barley seedlings may be related to their capacity to tolerate higher levels of reactive oxygen species.

0000-0002-9934-254X; 0000-0002-9432-1686; 0000-0002-2139-7655 WOS: 000427280700006 PubMed ID: 29435614 Boron (B) toxicity, which occurs in semi-arid and arid environments, can adversely affect the growth and yield of many plants. The aim of this study was to determine the effects of different concentrations of boric acid (3, 6, 9 and 12 mM) on growth, oxidative stress and genotoxicity parameters in root and shoot tissues of wheat seedlings. Our results indicate that B stress inhibits root and shoot growth of wheat in a concentration-dependent manner, and leads to increases in TBARS and H2O2 contents in shoot tissue. Moreover, our findings suggest that high concentrations of B may exert a genotoxic effect on wheat. To the best of our knowledge, this is the first report to evaluate the effect of B stress on genotoxicity in both root and shoot tissues of wheat. Scientific Research Projects Coordination Unit of Mugla Sitki Kocman UniversityMugla Sitki Kocman University [15/153] This study is one part of a PhD dissertation of the first author, funded by the Scientific Research Projects Coordination Unit of Mugla Sitki Kocman University (Grant Number 15/153).

0000-0002-9934-254X WOS: 000447392600001 PubMed ID: 30830436 IntroductionIt is well known that plant-derived smoke stimulates seed germination and seedling growth in many plants. Although a number of transcriptomics and proteomics studies have been carried out to understand the mode of action of smoke, less is known about the biochemical alterations associated with smoke exposure in plants.ObjectivesThe aims of this study were (1) to determine the metabolic alterations in maize roots pre-treated with various concentrations of smoke solution, and (2) to identify the smoke-responsive metabolic pathways during early root growth period.MethodsMaize seeds were pre-treated with different concentrations of smoke solutions for 24h and then grown for 10days. 600-MHz H-1 NMR spectroscopy was performed on the aqueous root extracts of maize seedlings. The metabolite data obtained from the NMR spectra were analyzed by several statistical and functional methods, including one-way ANOVA, PCA, PLS-DA and pathway analysis.ResultsOur study identified a total of 29 metabolites belonging to various chemical groups. Concentrations of 20 out of these 29 metabolites displayed significant (p

WOS: 000352506800013 Determining the relative role of various cues on seed germination in Mediterranean plants is important to understanding their response to variable conditions. We studied germination responses of 12 eastern Mediterranean Basin species (Alyssum caricum, A. minus, Carthamus dentatus, Daucus broteri, D. carota, Hypericum aviculariifolium, Muscari comosum, Onopordum caricum, Rumex crispus, Sarcopoterium spinosum, Silene vulgaris, Smyrnium rotundifolium) to different smoke and nitrate concentrations in laboratory. Smoke treatments resulted in significant increase in germination of D. carota, O. caricum, and S. spinosum, but had a negative effect on germination of Hypericum aviculariifolium. Of the 12 studied species, five showed significant improvement in germination after at least one of the nitrate treatments compared with the control. In total, smoke and nitrate treatments significantly increased the germination percentage in six of the 12 studied species. All the species that have smoke and/or nitrate-stimulated germination were propagule-persisters (P+), able to recruit after fire. The results reveal that both smoke and nitrate improve germination of Mediterranean species. Our results also suggest the presence of species specific germination response to smoke and nitrate in Mediterranean plants. Hacettepe University Scientific Research UnitHacettepe University [012.D06.601.0013] The seeds were collected in the field with the permission of the Ministry of Food, Agriculture and Livestock of Republic of Turkey (no: 1379, date: 09.03.2012). The experiments were conducted in the laboratories of Department of Biology, Mugla University, Turkey. The fieldwork of this study was supported by Hacettepe University Scientific Research Unit (project no. 012.D06.601.0013).