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Catalase (CAT) is an enzyme encoded by the catalase gene family that plays an important role in the removal of reactive oxygen species. In this study, seven CAT genes were identified in Nicotiana tabacum L. and were classified into three groups. Gene structure analysis revealed that NtCAT1–6 has six or seven introns while NtCAT7 only contains one. The relative position of introns in NtCAT1 and NtCAT2 had high similarity. Tissue-specific analysis shows that NtCAT1–4 were expressed intensively in the shoot while NtCAT5 and NtCAT6 were in the root. NtCAT7 expression was influenced by circadian rhythms. NtCATs expression had the greatest change under drought stress. Additionally, expression of NtCAT5, NtCAT6 and NtCAT7 were upregulated under cold stress but downregulated under drought and salt stress. This study will help in understanding the behavior of CAT genes during environmental stress in tobacco.

This study aimed to compare recombinant inbred lines (RIL) obtained via the bulk method with doubled haploid lines (DHL). For comparison, 190 DHL and 194 RIL were evaluated simultaneously at two different locations. Phenotypic and genetic parameters were estimated for the traits green leaf yield (GLY) and alkaloid content (ALK). The results of the RIL and DHL evaluations were similar for ALK. Conversely, estimates of genetic variation and heritability in the DHL were higher than those in the RIL for GLY. However, the mean estimate of the RIL was 13.3% higher than that of the DHL and thus, the annual gain with selection was higher for the RIL. The use of DHL in a recurrent selection program will be efficient in comparison to RIL if a large number of lines are obtained, which must undergo a preliminary selection before the most intensive evaluation to identify the lines to be recombined.

The SQUAMOSA promoter binding protein-like (SPL)SPL family genes play an important role in regulating plant growth and development, synthesis of secondary metabolites, and resistance to stress. Understanding of the role of the SPL family in tobacco is still limited. In this study, 42 NtSPL genes were identified from the genome of the tobacco variety TN90. According to the results of the conserved motif and phylogenetic tree, the NtSPL genes were divided into eight subgroups, and the genes in the same subgroup showed similar gene structures and conserved domains. The cis-acting element analysis of the NtSPL promoters showed that the NtSPL genes were regulated by plant hormones and stresses. Twenty-eight of the 42 NtSPL genes can be targeted by miR156. Transcriptome data and qPCR results indicated that the expression pattern of miR156-targeted NtSPL genes was usually tissue specific. The expression level of miR156 in tobacco was induced by Cd stress, and the expression pattern of NtSPL4a showed a significant negative correlation with that of miR156. These results suggest that miR156-NtSPL4a may mediate the tobacco response to Cd stress. This study lays a foundation for further research on the function of the NtSPL gene and provides new insights into the involvement of NtSPL genes in the plant response to heavy metal stress.

The antimicrobial properties of silver and enhanced reactivity when applied in a nanoparticle form (AgNPs) led to their growing utilization in industry and various consumer products, which raises concerns about their environmental impact. Since AgNPs are prone to transformation, surface coatings are added to enhance their stability. AgNP phytotoxicity has been mainly attributed to the excess generation of reactive oxygen species (ROS), leading to the induction of oxidative stress. Herein, in vitro-grown tobacco (Nicotiana tabacum) plants were exposed to AgNPs stabilized with either polyvinylpyrrolidone (PVP) or cetyltrimethylammonium bromide (CTAB) as well as to ionic silver (AgNO3), applied in the same concentrations, either alone or in combination with cysteine, a strong silver ligand. The results show a higher accumulation of Ag in roots and leaves after exposure to AgNPs compared to AgNO3. This was correlated with a predominantly higher impact of nanoparticle than ionic silver form on parameters of oxidative stress, although no severe damage to important biomolecules was observed. Nevertheless, all types of treatments caused mobilization of antioxidant machinery, especially in leaves, although surface coatings modulated the activation of its specific components. Most effects induced by AgNPs or AgNO3 were alleviated with addition of cysteine.

Root hairs absorb soil nutrients and water, and anchor the plant in the soil. Treatment of tobacco (Nicotiana tabacum) roots with glycine (Gly) amino acid, and glycilglycine (GlyGly) and glycilaspartic acid (GlyAsp) dipeptides (10−7 M concentration) significantly increased the development of root hairs. In the root, peptide accumulation was tissue-specific, with predominant localization to the root cap, meristem, elongation zone, and absorption zone. Peptides penetrated the epidermal and cortical cell and showed greater localization to the nucleus than to the cytoplasm. Compared with the control, tobacco plants grown in the presence of Gly, GlyGly, and GlyAsp exhibited the activation of WER, CPC, bHLH54, and bHLH66 genes and suppression of GTL1 and GL2 genes during root hair lengthening. Although Gly, GlyGly, and GlyAsp have a similar structure, the mechanism of regulation of root hair growth in each case were different, and these differences are most likely due to the fact that neutral Gly and GlyGly and negatively charged GlyAsp bind to different motives of functionally important proteins. Short peptides site-specifically interact with DNA, and histones. The molecular mechanisms underlying the effect of exogenous peptides on cellular processes remain unclear. Since these compounds acted at low concentrations, gene expression regulation by short peptides is most likely of epigenetic nature.

‘Isabel’ grape (Vitis labrusca x V. vinifera L. hybrid) is one of the main grape cultivars in Russia and some other countries for processing, due to its vigor, tolerance to the main fungal diseases, high yield and potential for sugar accumulation. The stilbene synthase gene VlvSTS was isolated from the hybrid grape cv. Isabel and cloned into a pSS plant transformation vector under the control of a constitutive 35S RNA double promoter of the cauliflower mosaic virus, CaMV 35SS. VlvSTS-gene containing transgenic tobacco lines were obtained and analyzed. For the first time plants expressing the VlvSTS gene were shown to have an enhanced resistance to the bacterial pathogen Erwinia carotovora subsp. carotovora B15. Transgenic plants were tested for resistance to a number of fungal pathogens. The plants were resistant to the grey mould fungus Botrytis cinerea, but not to the fungi Fusarium oxysporum, F. sporotrichioides, or F. culmorum. According to the results of a high performance liquid chromatography-mass spectrometry analysis, the amount of trans-resveratrol in leaves of transgenic plants with the highest expression of the VlvSTS gene was in a range from 150 to 170 μg/g of raw biomass. Change in the color and a decreased anthocyanin content in the flower corollas of transgenic plants were observed in transgenic lines with the highest expression of VlvSTS. A decrease in total flavonoid content was found in the flower petals but not the leaves of these tobacco lines. High expression of the VlvSTS gene influenced pollen development and seed productivity in transgenic plants. The size of pollen grains increased, while their total number per anther decreased. A decrease in the number of fertile pollen grains resulted in a decreased average weight of a seed boll in transgenic plants.

Bu çalışma ile Basma tipitütün hatlarının fenolojik ve morfolojik olarak tanımlanması, tütün ıslahıkonusunda yapılacak çalışmalara materyal hakkında bilgi verilmesihedeflenmiştir. Tarla denemeleri Orta Karadeniz Bölgesi’nde tütün üretiminin enfazla olduğu Bafra, Erbaa ve Gümüşhacıköy’de 4 farklı arazide yürütülmüştür.Morfolojik bakımdan yaprak tipi, yaşmak eni, aya şekli, yaprak ucu şekli, ayakabarcıklığı, yaprakta ondülelik ile alt yüzey orta damar rengi ve fenolojikbakımdan çiçeklenme zamanı, taç yaprak rengi ile çiçek kümesi şekliparametreleri incelenmiştir. Elde edilen sonuçlara göre; yaprak tipi bakımındangenotiplerin tamamı yaşmaklı, yaşmak eni bakımından %84’ü orta-geniş yaşmakenine sahip, aya şekli bakımından %92’si dar yada geniş eliptik, %92’si ortasivri yada sivri yaprak ucuna sahiptir. Çiçeklenme zamanı bakımındangenotiplerin %32’si geçci karakterli, %72’sinin taç yaprak rengi açık pembe vetamamının çiçek kümesi şekli küreseldir, In this study, it is aimed to define the Basmatype tobacco lines as phenological and morphological. In addition, it is aimedto give information about the materials to be used in the studies on tobaccobreeding. Field trials were conducted in 4 different locations in Bafra, Erbaaand Gümüşhacıköy districts where tobacco production was highest in the CentralBlack Sea Region. As morphological parameters, leaf type, width at blade, shapeof blade, leaf tip shape, blistering ofblade, undulations of margin and color of midrib on lower side and asphenological parameters, time of flowering, color of corolla and shape ofinflorescence have been investigated.According to the results, all genotypes in terms of leaf type are sessile. 84% of the width at blade basis has medium orbroad sessile width. 92% of the shape of blade is narrow elliptic or broadelliptic. 92% of the leaf tip shape is medium pointed or strongly pointed.According to time of flowering, 32% of the genotypes have late characteristics.%72 of color of corolla are light pink color and the shape of inflorescence ofall genotypes is spherical.

The stimulation effect of elevated [CO2] (e[CO2]) on plant growth is modulated by nitrogen (N) availability, yet the mechanisms of this modulation under patchy N supply remain largely elusive. This study aimed to investigate the mechanisms by which patchy nutrient supply in the root-zone influence on N uptake, partitioning and use efficiency of tobacco plants (Nicotiana tabacum L.) grown under e[CO2]. A split-root pot experiment was conducted on tobacco plants grown at ambient (a[CO2], 400 μmol L−1) and e[CO2] (800 μmol L−1) conditions during anthesis. Plants were subjected to two fertilizer levels [0 and 113-29-214 (N-P-K) mg kg−1 soil] and three fertilization regimes (partial root-zone fertilization, PRN, couple root-zone fertilization, CRN and no fertilization, CK). Elevated [CO2] significantly decreased N concentrations in all tobacco organs, with the greatest reduction in leaves. Positive responses of tobacco biomass and NUE to e[CO2] were recorded, and a large amount of 15N labelled fertilizer-N was partitioned to stems at the expense to leaves. Compared to the partially fertilized root, an equal N concentration was observed in the non-fertilized root. In addition, compared with CRN, PRN increased the root exudates of sugar and organic acid; however, the increased root biomass by nutrient patchiness did not enhance plant total N uptake. Collectively, e[CO2] could sustain N assimilation and distribution of tobacco plants in response to natural heterogeneous nutrient available in the soil caused by patchy fertilization.

Tobacco is a model plant for studying flower coloration. Flavonoids and carotenoids were reported to contribute to the flower color in many plants. We investigated the mechanism underlying flower color formation in tobacco by comparing the profiling flavonoids and carotenoids between various species Nicotiana tabacum L. and Nicotiana rustica L., as their flowers commonly presented red (pink) and yellow (orange), respectively. The metabolomes were conducted by UPLC–ESI–MS/MS system. The main findings were as follows: (1) A total of 31 flavonoids and 36 carotenoids were identified in all four cultivars involved in N. tabacum and N. rustica. (2) Flavonoids and carotenoids tended to concentrate in the red flowers (N. tabacum) and yellow flowers (N. rustica), respectively. (3) About eight flavonoids and 12 carotenoids were primarily screened out for metabolic biomarkers, such as the robust biomarker involving kaempferol-3-o-rut, quercetin-glu, rutin, lutein, and β-carotene. This is the first research of systematic metabolome involving both flavonoids and carotenoids in tobacco flower coloration. The metabolic mechanism concluded that flavonoids and carotenoids mainly contributed to red (pink) and yellow (orange) colors of the tobacco flowers, respectively. Our finding will provide essential insights into characterizing species and modifying flower color in tobacco breeding through genetic improvement or regulation of featured metabolic synthesis.

Protein yapısına katılmayan bir amino asit olan gamma amino bütirik asit (GABA), bitkilerde hem abiyotik ve biyotik stres yanıtlarında, hem de normal büyüme ve gelişme süreçlerinde önemli görevleri olduğu bilinen bir metabolittir. GABA’nın sirkadiyen ritmin düzenlenmesi ile ilişkili olduğuna konusunda bitkilerde ve memelilerde yapılmış çeşitli çalışmalar mevcuttur. Bununla birlikte, bitkilerde GABA’nın sirkadiyen ritim ile ilişkisi moleküler seviyede net olarak açıklanmamıştır. Tez projemizde Nicotiana tabacum L. (tütün) bitkisinde üç gün boyunca 24 saatlik zaman dilimlerinde yaprak örnekleri aldık. Yaprak örneklerinde GABA miktarındaki değişim ve GABA-yolunun önemli enzimleri olan glutamat dekarboksilaz (GAD) ve GABA transaminaz (GABA-T) aktiviteleri incelenmiştir. Bu analizlere paralel olarak sirkadiyen ritim ile ilgili seçilen sabah, merkezi ve akşam döngülerinde görevleri büyük ölçüde tanımlanmış circadian clock associated1 (CCA1), late elongated hypocotyl (LHY), gigantea (GI), timing of cab expresion1/pseudo-response regulator1 (TOC1/PRR1), pseudo-response regulator3 (PRR3), ve pseudo-reponse regulator7 (PRR7) transkript profillerindeki değişimler incelenmiştir., Gamma amino butyric acid (GABA), an amino acid that is not included in the protein structure. GABA known to play important roles both in abiotic and biotic stress responses and normal growth and development processes in plants. There are studies in plants and mammals showing that GABA is associated with the regulation of circadian rhythm. However, the relationship of GABA with the circadian rhythm in plants has not been clearly explained at the molecular level. In this thesis project, leaf samples were taken from Nicotiana tabacum L. (tobacco) plants for three days interval within 24-hour period. The differences in GABA content, glutamate decarboxylase (GAD) and GABA-transaminase (GABA-TP) activities were investigated in leaf samples. In parallel to these analyses, the transcript profiles of circadian clock associated1 (CCA1), late elongated hypocotyl (LHY), gigantea (GI), timing of cab expresion1/pseudo-response regulator1 (TOC1/PRR1), pseudo-response regulator3 (PRR3) and pseudo-reponse regulator7 (PRR7) genes which defined to have a role in the morning, central and evening loops of the circadian rhythm were also analyzed.

The research was aimed to develop genetic constructs for Agrobacterium-mediated plant transformation, containing the synthetic cry1Ab gene, and their testing through the transformation of tobacco, followed by a molecular genetic analysis of the obtained plants to confirm the transformation event. Basic methods of DNA cloning, Agrobacterium-mediated transformation of Nicotiana tabacum L. by leaf disc method, selection of transformants in vitro, analysis of the transgene presence in plant DNA, detection of cry1Ab gene expression by PCR with reverse transcription were used. In the course of the study, the vectors pCB182 and pCB241 that contained the synthetic gene cry1Ab were constructed. Agrobacterium-mediated transformation of tobacco was carried out by created vectors and regenerant plants containing transgenes in their DNA were obtained. Expression of cry1Ab transgene in the obtained transformants of tobacco by the RT-PCR method was confirmed. As a result of the Agrobacterium-mediated transformation of plants with pCB182 and pCB241 vectors containing the synthetic cry1Ab lepidopteran resistance gene it is possible to obtain transgenic plants with expression of the transgene.

The production of tobacco (Nicotiana tabacum L.) in Argentina is centered in the northwestern region (NWA), where the incidence of root rots and stem diseases caused by Fusarium spp. has increased considerably in recent years. This study aimed to evaluate the pathogenicity levels of isolates of the F. oxysporum and F. solani complexes in different varieties of Virginia Type tobacco. The commercial varieties MB47, PVH229, NC71, K346, K326, and K394 were inoculated with six isolates of both complexes. The variables evaluated were the incidence and severity of the symptoms. The area under the disease progress curves (AUDPC) was calculated and subjected to analysis of variance (ANOVA). Also, disease epidemiological models were fitted to the experimental data. The MB47 variety was significantly less infected and the varieties K346, K326, and K394 had the highest AUDPC means, showing susceptibility to the isolates. The disease intensity curves were adequately described by the monomolecular and logistic models. The results provide, for the first time, information about the levels of tolerance to vascular wilt and root rot under controlled conditions for the main varieties of Virginia-type tobacco grown in NWA. La producción de Tabaco (Nicotiana tabacum L.) en Argentina se concentra en la Región Noroeste (NOA), donde la incidencia de las enfermedades radiculares y de tallo causadas por Fusarium spp. han aumentado en los últimos años. Este estudio, tuvo como objetivo evaluar los niveles de patogenicidad de aislamientos de los complejos F. oxysporum y F. solani en diferentes variedades de tabaco tipo Virginia. Las variedades evaluadas fueron: MB47, PVH229, NC71, K346, K326 y K394 que se inocularon con seis aislamientos de ambos complejos. Las variables evaluadas fueron incidencia (I) y severidad (S). Se calculó el área bajo las curvas de progreso de la enfermedad (ABCPE) y se sometió a análisis de varianza (ANOVA). Además, se ajustaron los datos experimentales a modelos epidemiológicos del proceso de enfermedad. La variedad MB47 resultó significativamente menos infectada y las variedades K346, K326, K394 presentaron los valores de ABCPE más altos, mostrando un comportamiento susceptible. Las curvas de intensidad de la enfermedad se descri-bieron adecuadamente mediante los modelos monomolecular y logístico. Los resultados generados en el presente estudio proporcionan por primera vez información sobre los niveles de tolerancia al marchitamiento vascular y podredumbre radicular en condiciones controladas para las principales variedades de tabaco cultivadas en NOA. EEA Salta Fil: Berruezo, Lorena Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Berruezo, Lorena Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta; Argentina Fil: Harries, Eleonora Del Milagro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Harries, Eleonora Del Milagro. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta; Argentina Fil: Harries, Eleonora Del Milagro. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentina Fil: Galvan, Marta Zulema. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fil: Galvan, Marta Zulema. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta; Argentina Fil: Stenglein, Sebastian Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Cientifico Tecnolológico Mar del Plata. Instituto de Investigaciones en Biodiversidad y Biotecnología. Laboratorio de Biologia Funcional y Biotecnología; Argentina Fil: Stenglein, Sebastian Alberto. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Agronomia. Instituto de Investigaciones en Biodiversidad y Biotecnología. Laboratorio de Biología Funcional y Biotecnología; Argentina Fil: Mercado Cardenas, Guadalupe Eugenia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Salta; Argentina Fil: Mercado Cardenas, Guadalupe Eugenia. Universidad Nacional de Salta. Facultad de Ciencias Naturales; Argentina

Alternative splicing (AS) occurs extensively in eukaryotes as an essential mechanism for regulating transcriptome complexity and diversity, but the AS landscape regulating potassium (K) use efficiency in plants is unclear. In this study, we performed high-throughput transcriptome sequencing of roots and shoots from allopolyploid Nicotiana tabacum under K+ deficiency. Preliminary physiological analysis showed that root system architecture was dramatically changed due to potassium deficiency and that IAA content was significantly reduced in root and shoot. AS analysis showed that a total of 28,179 genes exhibited 54,457 AS events, and 1,510 and 1,732 differentially alternatively spliced (DAS) events were identified in shoots and roots under low K+ stress. Nevertheless, only 120 DAS events occurred in both shoots and roots, implying that most DAS events were tissue-specific. Both in shoot and the root, the proportion of DAS genes in differentially expressed (DE) genes equaled that in non-DE genes, which indicated that AS might play a unique regulatory role in response to low potassium. Gene ontology analysis further indicated that transcription regulation and AS modulation worked independently in response to low K+ stress in tobacco, as their target biological processes were different. Totally 45 DAS transcription factors (TFs) were found, which were involved in 18 TF families. Five Auxin response factor (ARF) TFs were significantly DAS in root, suggesting that response to auxin was probably subject to AS regulation in the tobacco root. Our study shows that AS variation occurs extensively and has a particular regulatory mechanism under K+ deficiency in tobacco. The study also links changes in root system architecture with the changes in AS of ARF TFs, which implied the functional significance of these AS events for root growth and architecture.

The biopolymer coating use on seeds has aroused the interest of the agricultural sector due to its low cost, reduction of impacts on the environment and improvements in productivity and yield of major crops, being chitosan an important polymer for application in seeds. Considering this knowledge, the present study aimed to evaluate the application effect of a bioproduct based on chitosan, from the parameters of physiological quality, vigor, and biochemistry in tobacco seeds. Seeds of the Virginia variety were submitted to treatments: 0.0 (witness); 0.5; 1; 2.5; 5; and 10% were used to obtain first count values, germination test, seedling length and fresh mass, and chlorophyll and carotenoid contents. The bioproduct had a positive effect on chlorophyll a, b, and carotenoids at 10% FTSeed concentration and seedling length under 5.25% FTSeed. The study pointed out that the bioproduct has a favorable action on the development and leaf pigments, being an alternative biostimulant with less impact on the environment for the agricultural sector. El uso de recubrimientos de biopolímeros en semillas ha despertado el interés del sector agrícola por su bajo costo, reducción de impactos ambientales y mejoras en la productividad y rendimiento de grandes cultivos, siendo el quitosano un polímero importante para estos fines. Sabiendo esto, el presente estudio tuvo como objetivo evaluar el efecto de la aplicación de un bioproducto a base de quitosano, a partir de los parámetros de calidad fisiológica, vigor y bioquímica en semillas de tabaco. Se utilizaron semillas de Virginia sometidas a los siguientes tratamientos: 0,0 (testigo); 0,5; 1; 2,5; 5; y 10%, para obtener valores de primer conteo, prueba de germinación, longitud de plántula y masa fresca, y contenido de clorofila y carotenoides. El bioproducto tuvo un efecto positivo sobre la clorofila a, b y los carotenoides a una concentración de FTSeed al 10 % y la longitud de las plántulas bajo FTSeed al 5,25 %. El estudio apuntó que el bioproducto tiene una acción favorable sobre el desarrollo y pigmentos foliares, siendo un bioestimulante alternativo y con menor impacto ambiental para el sector agrícola. O uso de revestimento de biopolímeros em sementes têm despertado o interesse do setor agrícola devido ao baixo custo, redução dos impactos ao ambiente e melhorias na produtividade e rendimento das grandes culturas, sendo a quitosana um importante polímero para essas finalidades. Sabendo disso, o presente estudo objetivou avaliar o efeito da aplicação de um bioproduto à base de quitosana, a partir dos parâmetros de qualidade fisiológica, vigor e bioquímica em sementes de fumo. Foram utilizadas sementes da variedade Virginia submetidas aos tratamentos: 0,0 (testemunha); 0,5; 1; 2,5; 5; e 10%, para obtenção de valores de primeira contagem, teste de germinação, comprimento e massa fresca de plântula, e teores de clorofila e carotenoides. O bioproduto desempenhou efeito positivo sobre a clorofila a, b e carotenoides na concentração de FTSeed a 10% e comprimento das plântulas sob FTSeed a 5,25%. O estudo apontou que o bioproduto desempenha ação favorável sobre o desenvolvimento e pigmentos foliares, sendo um bioestimulante alternativo e de menor impacto ao ambiente para o setor agrícola.

The use of late flowering tobacco lines becomes essential in breeding programs due to their morphological traits. These strains present a long vegetative period when cultivated at a given time, making it difficult to collect pollen and crosses. The objectives of this work were: to induce the early flowering of tobacco genotypes by the application of gibberellic acid (GA3) and by cultivation in root-restricted pots and to analyze the economic viability in anticipating the flowering of tobacco genotypes. The completely randomized design was used, with five replications, composed of a factorial with five genotypes (K326, KM10, LF, TN90 and BU459) and four concentrations of gibberellic acid (0, 50, 100 and 200 mgL-¹ of GA3) and five additional treatments (genotypes in smaller pots). The data were submitted to an analysis of individual variance and for the traits number of flowers in the 5th; 10th; 20th; 30th day; sum of flowers; and seed mass regression analysis was performed, and the genotype x GA3 concentration interaction was significant. For the additional ones, a means test was performed. The factorial treatments showed early floral induction for the highest GA3 concentration in both seasons as well as the additional treatments, except for LF genotypes (exp. I) and TN90 (exp. II). The sum of flowers and grain mass showed a suppression with the highest GA3 concentrations and in the additional treatments. A savings of 14.5% was obtained by inducing early flowering of tobacco genotypes. A utilização de linhagens de tabaco de florescimento tardio torna-se essencial nos programas de melhoramento devido suas características morfológicas. Essas linhagens apresentam período vegetativo longo quando cultivadas em determinada época, dificultando a coleta de pólen e os cruzamentos. Os objetivos desse trabalho foram: induzir o florescimento precoce de genótipos de tabaco pela aplicação de ácido giberélico (GA3) e pelo cultivo em vasos com restrição radicular e analisar a viabilidade econômica em antecipar o florescimento de genótipos de tabaco. O delineamento inteiramente ao acaso foi utilizado, com cinco repetições, composto por um fatorial com cinco genótipos (K326, KM10, LF, TN90 e BU459) e quatro concentrações de ácido giberélico (0, 50, 100 e 200 mgL-¹ de GA3) e cinco tratamentos adicionais (genótipos em vasos menores). Os dados foram submetidos a uma análise de variância individual e para os caracteres número de flores no 5º; 10º; 20º; 30º dia; soma de flores; e massa de sementes foi realizada análise de regressão, sendo significativa a interação genótipo x concentração de GA3. Para os adicionais, foi realizado um teste de médias. Os tratamentos fatoriais apresentaram indução floral antecipada para a maior concentração de GA3 nas duas épocas bem como os tratamentos adicionais, exceto os genótipos LF (exp. I) e TN90 (exp. II). A soma de flores e a massa de grãos apresentaram uma supressão com as maiores concentrações de GA3 e nos tratamentos adicionais. Uma economia de 14,5% foi obtida com a indução do florescimento precoce de genótipos de tabaco.

The article presents a comparative analysis of various methods and conditions of extraction from the plant Nicotiana tabacum l, harvested in the Almaty region of the Republic of Kazakhstan in 2018. The study of extracts obtained by the traditional method (Extraction using non-polar organic solvents at atmospheric pressure) of solvent extraction in particular hexane, and the method of supercritical fluid extraction, carbon dioxide, under various conditions of the process. Three different supercritical extraction modes were selected, namely: at a relatively low pressure of 120 bar and a low temperature of 28°C, at an elevated temperature with the same pressure (60°C, 120 bar) and at an elevated temperature and pressure (80°C , 170 bar). As a result of studying the obtained extracts by GC-MS, their qualitative and quantitative composition was identified. It has been established that the largest number of various compounds is extracted by supercritical fluid extraction at a relatively low pressure of 150 bar for this method and a low temperature of 28°C, but the most popular compound in the studied raw material, nicotine, is extracted with approximately the efficiency similar to the classical method. To increase the yield of the target component, the extraction conditions were changed. As a result, a significant increase in the degree of extraction of the target product was achieved under the following conditions: pressure 120 bar, temperature 60°C. Under these conditions, the degree of extraction was 47.40%. Conducted to control and more fully study the laws of the extraction process (at elevated pressure) showed less efficiency, only 12.29%. This result is lower in efficiency than the classical extraction method. From the data obtained, it follows that for the extraction of nicotine, a substance belonging to the class of alkaloids and which is resistant to thermal destruction, preferred and most effective, is the mode of supercritical extraction at a temperature of 60°C and a pressure of 120 bar.

The transgenic tobacco (Nicotiana tabacum L.) plants with the modified levels of alternative oxidase (AOX) were used to evaluate the physiological roles of AOX in regulating nitro-oxidative stress and metabolic changes after exposing plants to hypoxia for 6 h. Under normoxia, AOX expression resulted in the decrease of nitric oxide (NO) levels and of the rate of protein S-nitrosylation, while under hypoxia, AOX overexpressors exhibited higher NO and S-nitrosylation levels than knockdowns. AOX expression was essential in avoiding hypoxia-induced superoxide and H2O2 levels, and this was achieved via higher activities of catalase and glutathione reductase and the reduced expression of respiratory burst oxidase homolog (Rboh) in overexpressors as compared to knockdowns. The AOX overexpressing lines accumulated less pyruvate and exhibited the increased transcript and activity levels of pyruvate decarboxylase and alcohol dehydrogenase under hypoxia. This suggests that AOX contributes to the energy state of hypoxic tissues by stimulating the increase of pyruvate flow into fermentation pathways. Ethylene biosynthesis genes encoding 1-aminocyclopropane-1-carboxylic acid (ACC) synthase, ACC oxidase, and ethylene-responsive factors (ERFs) were induced during hypoxia and correlated with AOX and NO levels. We conclude that AOX controls the interaction of NO, reactive oxygen species, and ethylene, triggering a coordinated downstream defensive response against hypoxia.

Nicotiana tabacum L. (NTL) is an important agricultural and economical crop. Its maturity is one of the key factors affecting its quality. Traditionally, maturity is discriminated visually by humans, which is subjective and empirical. In this study, we concentrated on detecting as many compounds as possible in NTL leaves from different maturity grades using ultra-performance liquid chromatography ion trap time-of-flight mass spectrometry (UPLC-IT-TOF/MS). Then, the low-dimensional embedding of LC-MS dataset by t-distributed stochastic neighbor embedding (t-SNE) clearly showed the separation of the leaves from different maturity grades. The discriminant models between different maturity grades were established using orthogonal partial least squares discriminant analysis (OPLS-DA). The quality metrics of the models are R2Y = 0.939 and Q2 = 0.742 (unripe and ripe), R2Y = 0.900 and Q2 = 0.847 (overripe and ripe), and R2Y = 0.972 and Q2 = 0.930 (overripe and unripe). The differential metabolites were screened by their variable importance in projection (VIP) and p-Values. The existing tandem mass spectrometry library of plant metabolites, the user-defined library of structures, and MS-FINDER were combined to identify these metabolites. A total of 49 compounds were identified, including 12 amines, 14 lipids, 10 phenols, and 13 others. The results can be used to discriminate the maturity grades of the leaves and ensure their quality.

This study examined the use of an innovative tobacco variety, Nicotiana tabacum L., cv. Solaris, as forage. The whole plant biomass was ensiled, and the composition of SiloSolaris from bunker-silo and mini-silos was investigated. The effects of dietary inclusion of SiloSolaris on the growth, welfare, and nutritional profile of sixteen Holstein heifers, divided into two groups (n = 8), SiloSolaris (SS) and Control (CTR), were investigated. Heifers were group-fed diets with a 70:30 forage to concentrate ratio (on a DM basis). Both groups received 16.24 kg DM of concentrate mixture daily, including corn meal, wheat middlings and soybean meal. The CTR group was fed 39.43 kg DM of hay daily, and the SS group received 23.00 kg DM of the same hay and 12.69 kg DM SiloSolaris blended with the concentrate mixture. The feeding trial lasted eighty-one days with a thirty-six day adaptation phase. Data on forty-five days of diet administration are reported. At the end of the feeding trial, the plasma constituents of the heifers were studied. Moreover, heifers were monitored during a follow-up period, lasting up to 1 year after calving, for age at first insemination, age at first calving and daily milk yield. The SiloSolaris chemical composition showed an average DM content of 24.1 (±0.65) g/100 g. During ensiling, a decrease in CP and an increase in ammonia nitrogen contents were observed. The lactic acid content was variable (9.00 ± 2.66 g/100 g DM), while the acetic acid concentration was stable (4.27 ± 0.21 g/100 g DM). No butyric acid was detected in SiloSolaris, whose ammonia nitrogen content accounted for 15.7 (±1.86)% of the total nitrogen on average, and the mean pH value was 5.02 (±0.08). The SiloSolaris diet did not affect heifer growth performance. No differences were detected for body condition, fecal consistency, or locomotion scores. All the investigated plasma constituents were within or very close to the ranges reported for heifers; however, significant differences between the experimental groups were observed for triglycerides, cholesterol, albumin, and magnesium. The follow-up results did not differ between the experimental groups. These initial findings suggest that Nicotiana tabacum cv. Solaris is a promising ensiled forage for growing heifers that deserve to be further investigated.

Leaf area is an important growth variable in agricultural crops and the leaf is the main variable of interest in the tobacco industry. So, the aim of this scientific research was to estimate the Burley tobacco leaf area by linear dimensions of the leaves and to determine which mathematical model is more adequate for this purpose. Two experiments were carried out with Burley tobacco, cultivar DBH 2252, in 2016/2017 and 2018/2019 agricultural years, respectively, in the municipalities of Itaqui and Vanini - RS - Brazil. In 600 leaves were measured length (L), width (W), length×width product (LW), length/width ratio (L/W) and determined the real leaf area (LA). Four hundred and fifty leaves were separated to generate models of the leaf area as a function of linear dimension and the other 150 leaves were used for model’s validation. The power model LA = 0.5037LW1.04435 (R² = 0.9960) is the most adequate for Burley tobacco ‘DBH 2252’ leaf area estimation. Alternatively, the models LA=2.0369W1.8619 (R²=0.9796) and LA=0.1222L2.2771 (R²=0.9738) based on width and length, respectively, can be used when only one leaf dimension is measured.

Tobacco is an annual cash crop widely cultivated over the world, which generally needs great amounts (N) of nitrogen to achieve the best yield and quality. However, with a view to sustainable and environmentally friendly agriculture, also for this crop, the reduction in N fertilization is a priority, but without negatively affecting the yield and quality of the cured product. Therefore, field experiments were conducted during 2002 and 2003 on light air-cured (Burley) tobacco at three different locations of the Campania region (Southern Italy) where high-quality light air-cured (Burley) tobacco is traditionally cultivated. At each location, the following six N fertilization treatments were compared with four replications (blocks): (i) a not fertilized control (N0), (ii) 50 kg N ha−1 (N50), 90 kg N ha−1 (N90), 130 kg N ha−1 (N130), 170 kg N ha−1 (N170), 210 kg N ha−1 (N210). The yield of cured leaves appeared positively influenced by N fertilization but not at a rate higher than 170 kg ha−1. N fertilization directly influenced nitrates and the total N content of cured leaves at all locations. The greater values of both parameters were reached at N130 or N90, respectively, at Vitulazio (CE), N170 at Bellizzi (SA), and N90 at San Giorgio del Sannio (BN). The fire holding capacity increased with N fertilization up to N170 treatment (12–13 s at CE and BN but just 8 s at SA). L* (brightness) decreased with increasing N fertilization giving cured leaves less bright and opaquer. The a/b ratio (a*, green/red, b*, blue/yellow) increased with N treatments producing cured leaves of dark hazelnut. The best scores were assigned to cured products obtained by plants fertilized with 170 kg N ha−1. N-use efficiencies were negatively influenced by N fertilization. The best NUE and N-uptake efficiency was recorded in 2002 at Vitulazio (CE), in spite of a higher NO3-N before N fertilization than other locations.

Made available in DSpace on 2022-04-28T19:44:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Proline plays adaptive roles in plant tolerance to cadmium (Cd)-induced stress, but many gaps remain to be elucidated as the responses triggered by exogenously supplied proline or endogenously overproduction are not well known. Thus, we assayed the nutritional status, metabolite profiling, and antioxidative responses in wild type and transgenic tobacco (Nicotiana tabacum L.) containing the P5CSF129A gene under control of the cauliflower mosaic virus (CaMV35S) or stress inducible rd29A promoters. The plants were exposed or unexposed to Cd (0 and 50 μmol L−1 CdCl2·H2O) for 24 and 72 h. The wild type plants were also treated with or without exogenous proline (1 mmol L−1). Plants supplied with exogenous proline exhibited lower Cd translocation from roots to leaves than plants overproducing proline, avoiding oxidative damages in the leaves of these plants. Meanwhile, tobacco overproducing proline was less susceptible to Cd-induced nutritional changes than wild type plants and presented better metabolic adjustment under Cd exposure compared to plants supplied with exogenous proline. Plants overproducing proline increased the synthesis of sugars and organic acids under Cd exposure, which contributed to absence of oxidative stress, since both superoxide dismutase and catalase were not active against Cd-induced oxidative stress in these genotypes. Plants overproducing proline under the control of rd29A presented higher proline concentration in comparison to the CaMV35S promoter. With exception of rd29A plants that presented high proline and reduced glutathione (GSH) concentrations, the other plants presented an inverse correlation between proline and GSH synthesis after 72 h of Cd exposure. College of Agriculture Luiz de Queiroz University of São Paulo Center for Nuclear Energy in Agriculture University of São Paulo Centre for Environmental Sciences Hasselt University Institute of Biosciences São Paulo State University Department of Mathematics Federal University of Technology of Paraná Federal University of Technology of Paraná Department of Agronomy University of Oeste Paulista Laboratório de Genética Bioquímica de Plantas Departamento de Genética Escola Superior de Agricultura “Luiz de Queiroz”, Avenida Pádua Dias, 11, Caixa Postal 9 Institute of Biosciences São Paulo State University

International audience; A Cu-resistant somaclonal tobacco variant (NBCu 10-8-F1, C1), its BaG mother clone (C3), and the FoP tobacco clone (C2) were cultivated at a wood preservation site on Cu-contaminated soils (239-1290 mg Cu kg(-1) soil range) and an uncontaminated control site (CTRL, 21 mg Cu kg(-1)) to assess their shoot DW yields and potential use for bioavailable Cu stripping. The Cu concentration in the soil pore water varied between 0.15 and 0.84 mg L-1. Influences of Cu exposure and soil treatments, i.e., untreated soil (Unt), soils amended with compost and either dolomitic limestone (OMDL) or zerovalent iron grit (OMZ), on plant growth and shoot ionome were determined. All transplants survived and grew even at high total soil Cu. Shoots were harvested after 3 months (cut 1). Subsequently, bottom suckers developed and were harvested after 2 months (cut 2). Total shoot DW yield (cuts 1 + 2) varied between 0.8 and 9.9 t DW ha(-1) year(-1) depending on tobacco cultivars, soil treatments, and soil Cu exposure. It peaked for all cultivars in the OMDL plots at moderate Cu exposure (239-518 mg kg(-1) soil), notably for the C2 plants. Cut 2 contributed for 11-43% to total shoot DW yield. Increase in shoot DW yield diluted shoot Cu concentration. At low Cu exposure, total shoot Cu removal peaked for the variant. At moderate Cu exposure, shoot Cu concentrations were similar in all cultivars, but total shoot Cu removal was highest for the C2 plants. At high Cu exposure (753-1140 mg kg(-1)), shoot Cu concentrations peaked for the C2 plants in the Unt plots, the C1 and C2 plants in the OMZ plot, and the C3 ones in the OMDL plots. Shoot Cu removal (in g Cu ha(-1) year(-1)) ranged from 15.4 (C2 on the CTRL soil) to 261.3 (C2 on moderately contaminated OMDL soils). The C2 plants phytoextracted more Cu than the C1 and C3 ones in the Unt plots and in the OMDL plots at moderate Cu exposure. In the OMDL plots with high Cu exposure, shoot Cu removal was highest for the C1 plants. Soil amendments improved shoot Cu removal through increase in either shoot DW yield (OMDL-3-fold) or shoot Cu concentration (OMZ-1.3-fold). Increased shoot Cu concentration induced an ionome imbalance with increased shoot Al, Fe, B, and Mg concentrations and decreased P and K ones. Copper concentrations in plant parts varied in decreasing order: roots > leaves > inflorescence (cymes including seeds) > stem, whereas Cu removal ranked as roots > stem = leaves > inflorescence.

Silver nanoparticles (AgNPs) are used in a wide range of consumer products because of their excellent antimicrobial properties. AgNPs released into the environment are prone to transformations such as aggregation, oxidation, or dissolution so they are often stabilised by coatings that affect their physico-chemical properties and change their effect on living organisms. In this study we investigated the stability of polyvinylpyrrolidone (PVP) and cetyltrimethylammonium bromide (CTAB) coated AgNPs in an exposure medium, as well as their effect on tobacco germination and early growth. AgNP-CTAB was found to be more stable in the solid Murashige and Skoog (MS) medium compared to AgNP-PVP. The uptake and accumulation of silver in seedlings was equally efficient after exposure to both types of AgNPs. However, AgNP-PVP induced only mild toxicity on seedlings growth, while AgNP-CTAB caused severe negative effects on all parameters, even compared to AgNO3. Moreover, CTAB coating itself exerted negative effects on growth. Cysteine addition generally alleviated AgNP-PVP-induced negative effects, while it failed to improve germination and growth parameters after exposure to AgNP-CTAB. These results suggest that the toxic effects of AgNP-PVP are mainly a consequence of release of Ag+ ions, while phytotoxicity of AgNP-CTAB can rather be ascribed to surface coating itself.