Potencial dendrocronológico de tres especies de Podocarpáceas de la Cordillera de los Andes / Dendrochronological potential of three Podocarpaceae species from the Andean Cordillera

Resumen Introducción: Poco se conoce del potencial dendrocronológico de las Podocarpáceas en el trópico. Objetivo: Explorar el potencial dendrocronológico de tres especies de podocarpáceas: Retrophyllum rospigliosii, Podocarpus oleifolius y Prumnopitys harmsiana. Métodos: De plantaciones no manejadas localizadas en los Andes colombianos, se muestrearon y analizaron 88 árboles: 30 muestras de R. rospigliosii provenientes de secciones transversales, 30 y 28 muestras de P. oleifolius y P. harmsiana, respectivamente, provenientes de núcleos de madera extraídos con barreno de incrementos. Las muestras se procesaron siguiendo las técnicas dendrocronológicas estándar. Resultados: En general, las características anatómicas de los anillos de crecimiento son similares para las tres especies, con una anatomía simple de traqueidas alineadas radialmente por tratarse de coníferas. Dado que la edad conocida de la plantación coincide con el número de anillos se considera una fuerte evidencia de la frecuencia anual de su formación en R. rospigliosii y P. oleifolius, las cuales presentaron buena sincronización (cofechado) con una inter-correlación promedio de 0.55 (r-Pearson). Para P. harmsiana no fue posible concretar series de ancho de anillos de las muestras recolectadas. Las series estandarizadas de R. rospigliosii y P. oleifolius mostraron una relación con los registros instrumentales de precipitación y temperatura, indicando que estas especies pueden ser promisorias para estudios adicionales. Conclusión: La investigación dendrocronología con especies de Podocarpáceas podría realizarse exitosamente con R. rospigliosii y P. oleifolius, pero no con P. harmsiana.

Abstract Introduction: Little is known about the dendrochronological potential of Podocarpaceaes in the tropics. Objective: To explore the dendrochronological potential of three Podocarpaceae species: Retrophyllum rospigliosii, Podocarpus oleifolius, and Prumnopitys harmsiana. Methods: From a non-managed plantation in the Andean cordillera in Colombia, a total of 88 trees were analyzed: 30 samples of cross-sections of R. rospigliosii, and 30 and 28 samples of P. oleifolius and P. harmsiana, respectively, obtained with an increment borer. Samples were processed according to standard dendrochronological methods. Results: The anatomical characteristics of the growth rings of the three species are similar, with a simple conifer anatomy with radially oriented tracheids. Since the known age of the plantation coincides with the number of tree rings this is strong evidence of annual tree-ring frequency of R. rospigliosii and P. oleifolius which also showed a satisfactory cross-dating with an average inter-correlation of 0.55 (r-Pearson). For P. harmsiana, it was not possible to build a tree-ring series from the collected samples. R. rospigliosii and P. oleifolius standardized ring-width chronologies showed a relationship with the instrumental records of rainfall and temperature, indicating these species may be promising further studies. Conclusions: Dendrochronological research with Podocarpaceae species could be carried out successfully with R. rospigliosii and P. oleifolius but not with P. harmsiana.

Genome-wide identification of SUN gene family in Fragaria vesca and stresses-response analysis / 生物工程学报

SUN gene is a group of key genes regulating plant growth and development. Here, SUN gene families of strawberry were identified from the genome of the diploid Fragaria vesca, and their physicochemical properties, genes structure, evolution and genes expression were also analyzed. Our results showed that there were thirty-one FvSUN genes in F. vesca and the FvSUNs encoded proteins were classified into seven groups, and the members in the same group showed high similarity in gene structures and conservative motifs. The electronic subcellular localization of FvSUNs was mainly in the nucleus. Collinearity analysis showed that the members of FvSUN gene family were mainly expanded by segmental duplication in F. vesca, and Arabidopsis and F. vesca shared twenty-three pairs of orthologous SUN genes. According to the expression pattern in different tissues shown by the transcriptome data of F. vesca, the FvSUNs gene can be divided into three types: (1) expressed in nearly all tissues, (2) hardly expressed in any tissues, and (3) expressed in special tissues. The gene expression pattern of FvSUNs was further verified by quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, the seedlings of F. vesca were treated by different abiotic stresses, and the expression level of 31 FvSUNs genes were assayed by qRT-PCR. The expression of most of the tested genes was induced by cold, high salt or drought stress. Our studies may facilitate revealing the biological function and molecular mechanism of SUN genes in strawberry.

Application of virus-induced gene silencing technology to investigate the phytochrome metabolism mechanism: a review / 生物工程学报

Color is an important indicator for evaluating the ornamental traits of horticultural plants, and plant pigments is a key factor affecting the color phenotype of plants. Plant pigments and their metabolites play important roles in color formation of ornamental organs, regulation of plant growth and development, and response to adversity stress. It has therefore became a hot topic in the field of plant research. Virus-induced gene silencing (VIGS) is a vital genomics tool that specifically reduces host endogenous gene expression utilizing plant homology-dependent defense mechanisms. In addition, VIGS enables characterization of gene function by rapidly inducing the gene-silencing phenotypes in plants. It provides an efficient and feasible alternative for verifying gene function in plant species lacking genetic transformation systems. This paper reviews the current status of the application of VIGS technology in the biosynthesis, degradation and regulatory mechanisms of plant pigments. Moreover, this review discusses the potential and future prospects of VIGS technology in exploring the regulatory mechanisms of plant pigments, with the aim to further our understandings of the metabolic processes and regulatory mechanisms of different plant pigments as well as improving plant color traits.

What is the optimal fertigation start time and frequency in lettuce seedlings?

Although lettuce is one of the most important vegetable crops cultivated in Brazil, producers conduct seedling production empirically, as there are no published reports on the optimal start time and management strategy for seedling fertigation. The present aimed to assess the influence of fertigation management on the growth, physiological aspects and nutritional status of lettuce seedlings and to determine the optimal fertigation start time and frequency. Two experiments were conducted, each with a randomized block design and six repetitions. The first consisted of six treatments, namely six fertigation start times at 0, 3, 6, 9, 12, and 15 d after emergence (DAE), and the second consisted of five treatments, representing different application frequencies at 3, 4, 5, 6, and 7 d intervals. The assessment of nutrient accumulation levels and biometric and physiological characteristics of the seedlings were performed after transplanting. Fertigation start times significantly affected 14 of the 18 variables assessed, particularly the number of leaves, shoot dry weight, leaf area, initial chlorophyll fluorescence, and P, K, Ca, Mg, and S accumulation. The best results for ten variables were obtained when fertigation began at emergence, with values 17.77 - 35.63% higher than those at fertigation onset at 15 DAE. Application frequency only influenced chlorophyll content and N, P, K, and S accumulation, with optimal results obtained at 3 - 6 d intervals. Beginning fertigation at plant emergence favors dry weight production, nutrition and photosynthesis and shortens the production time of lettuce seedlings. The optimal start time for lettuce seedling fertigation is at emergence, with application performed every 6 d.

Aftershocks of the Samarco disaster: diminished growth and increased metal content of Raphanus sativuscultivated in soil with mining tailings

The collapse of the Fundão tailings dam of the Samarco mining complex in Mariana, Brazil, was the largest mining disaster in the world to date with many socio-economic and environmental impacts. Soil affected by mining tailings was severely altered with negative impacts for agriculture. We tested whether diluting mining tailings with organic soil would eliminate or at least attenuate the ecotoxic effects on plant development and performance. We cultivated radish, Raphanus sativus,in substrates containing different proportions of mining tailings and organic soil: pure tailings (T100%); 2) tailings75%+ soil25%(T75%); 3) tailings50%+ soil50%(T50%); 4) tailings25%+ soil75%(T25%), and 5) pure organic soil (Soil100%, control). There were large differences in soil quality parameters between the 100% tailings treatment (T100%) and the control (Soil100%), as well as for some parameters in the most diluted treatment -T25%(Ca2+, Fe, Mn) in relation to the controltreatment. Although dilution of the tailings soil improved radish development, there was lower radish productivity (leaf area, total biomass, and root/tuber biomass) than for pure soil (control). There were also significantly higher amounts of bioaccumulated metals in radish tubers grown with tailings, even when grown in T25%for Fe content and in T75%for Mn content. These results present a worrisome scenario for human communities in the region of the Doce river, as human consumption of crops produced in soil contaminated with tailingsis not recommended due to potential toxicological effects from high metal concentrations.(AU)

Growth of Schizolobium parahyba var. amazonicum seedlings by strains of Trichoderma spp. under boron rates

Brazil has many important native species, which includes Schizolobium parahyba var. amazonicum (Huber ex Ducke) Barneby, however, the growth of this species is inhibited in soils with low boron contents, or excess boron, which causes phytotoxicity. Applications of strains of Trichoderma spp. increase the plants' tolerance to abiotic stresses, including tolerance to low or excess levels of nutrients such as boron (B). Thus, the objective of this work was to evaluate plant development and the effect of strains of Trichoderma spp. in Schizolobium parahyba var. amazonicum seedlings grown under different boron rates. A randomized block experimental design was used, with a 4×5 factorial scheme, consisting of 4 strains of Trichoderma spp. and 5 B rates (0, 0.5, 1.0, 1.5, and 2.0 mg dm-3), with seven replications, in greenhouse. Plant height, stem diameter, fresh and dry mass, leaf, stem and total were evaluated at 120 days after emergence. The stains of Trichoderma spp. and B rates presented significant interaction for all evaluated variables, decreasing phytotoxicity. The strain IBLF006WP (T. harzianum) showed a higher capacity of increasing the plants' tolerance to boron, followed by URM5911 (T. asperellum). However, the beneficial effect of increasing this tolerance with the application of these strains is only feasible for soils with high contents of this micronutrient in the soil.

Formins: the key regulators of plant cell morphology and development / 生物工程学报

Formins are widely distributed in eukaryotes such as fungi, plants and animals. They play crucial roles in regulating the polymerization of actin, coordinating the synergistic interactions between actin and microtubules, and determining cell growth and morphology. Unlike formins from fungi and animals, plant formins have been evolved into two plant-specific types. Generally, type Ⅱ formins are believed to regulate the polarized growth of cells, and type Ⅰ formins may regulate the cell expansion and division processes. Recent studies on the function of plant formins suggest it is inappropriate to classify the function of formins purely based on their structures. This review summarizes the domain organization of formins and their corresponding functions, as well as the underpinning mechanisms. Furthermore, the unsolved or unexplored issues along with future perspectives on plant formins are proposed and discussed.

Research progress on mechanism of phytohormones in regulating flavonoid metabolism / 中国中药杂志

Phytohormones play an important role at all stages of plant growth, influencing plant growth and development and regulating plant secondary metabolism, such as the synthesis of flavone, flavonol, anthocyanin, and other flavonoids. Flavonoids, a group of important secondary metabolites ubiquitous in plants, have antioxidative, anti-microbial, and anti-inflammatory activities and thus have a wide range of potential applications in Chinese medicine and food nutrition. With the development of biotechnology, phytohormones' regulation on flavonoids has become a research focus in recent years. This study reviewed the research progress on the mechanism of common phytohormones, such as abscisic acid, gibberellin, methyl jasmonate, and salicylic acid, in regulating flavonoid metabolism, and discussed the molecular mechanism of the synthesis and accumulation of flavonoids, aiming at clarifying the key role of phytohormones in modulating flavonoid metabolism. The result is of guiding significance for improving the content of flavonoids in plants through rational use of phytohormones and of reference value for exploring the mechanism of hormones in regulating flavonoid metabolism.

Molecular mechanisms of RPD3 family members in regulating plant development and environmental responses / 生物工程学报

Lysine acetylation is one of the major post-translational modifications and plays critical roles in regulating gene expression and protein function. Histone deacetylases (HDACs) are responsible for the removal of acetyl groups from the lysines of both histone and non-histone proteins. The RPD3 family is the most widely studied HDACs. This article summarizes the regulatory mechanisms of Arabidopsis RPD3 family in several growth and development processes, which provide a reference for studying the mechanisms of RPD3 family members in regulating plant development. Moreover, this review may provide ideas and clues for exploring the functions of other members of HDACs family.

Progress of studies on ATP-binding cassette transporters and transportation of secondary metabolites in medicinal plants / 中国中药杂志

ATP-binding cassette(ABC) transporters are one of the largest protein families in organisms, with important effects in regulating plant growth and development, root morphology, transportation of secondary metabolites and resistance of stress. Environmental stress promotes the biosynthesis and accumulation of secondary metabolites, which determines the quality of medicinal plants. Therefore, how to improve the accumulation of secondary metabolites has been a hotspot in studying medicinal plants. Many studies have showed that ABC transporters are extremely related to the transportation and accumulation of secondary metabolites in plants. Recently, with the great development of genomics and transcriptomic sequencing technology, the regulatory mechanisms of ABC transporters on secondary metabolites have attached great attentions in medicinal plants. This paper reviewed the mechanisms of different groups of ABC transporters in transporting secondary metabolites through cell membranes. This paper provided key theoretical basis and technical supports in studying the mechanisms of ABC transporters in medicinal plant, and promoting the accumulation of secondary metabolites, in order to improve the quality of medicinal plants.

Molecular mechanism of WRKY12 in regulating plant development / 生物工程学报

WRKY transcription factors are one of the largest families of transcription factors in higher plants and involved in regulating multiple and complex growth and development processes in plants. WRKY12 is a typical member of WRKY family. This article summarizes recent research progresses on the regulatory mechanism of WRKY12 in multiple growth and development processes, and analyzes the functional differences between WRKY12 and WRKY13. It provides a useful reference for further studying the molecular mechanism of WRKY12 in plant complex developments. It also provides clearer research ideas and reference strategies for exploring the self-regulation of other WRKY member and the mutual regulatory relationships between different WRKY family genes.

Conservation of Vriesea flammea L. B. Sm., an endemic Brazilian bromeliad: effects of nutrients and carbon source on plant development / Conservação de Vriesea flammea L. B. Sm., uma bromélia Brasileira endêmica: efeitos dos nutrientes e fonte de carbono sobre o desenvolvimento das plantas

Abstract Bromeliaceae is restricted to the Neotropical region and has a high degree of endemism, which contributes to increased biodiversity because of the diverse morphological characteristics of individuals. In order to develop an in vitro conservation technology to obtain plants for reintroduction, seeds of Vriesea flammea L.B.Sm. were collected, sterilized and germinated in culture medium. The plants obtained were cultured for 180 days in MS medium with different concentrations of mineral nutrients (25 and 50% of nitrogenous salts and macronutrients), and different concentrations of sucrose (20, 30, 40, 50 and 60 g L-1), and then acclimatized for 150 days on commercial substrate. When seeds were sterilized directly, only 4% of them were contaminated, whereas sterilization of capsules resulted in 43.6% contaminated seeds. Germination rates above 80% were recorded. Low concentrations of nitrogenous salts and macronutrients produced greater than 76% survival and promoted greater in vitro plant development than the complete MS medium. The development of the aerial system, root system, fresh mass and photosynthetic pigments were positively related to sucrose concentration in vitro. The highest sucrose concentration also indirectly promoted greater development of the aerial system and fresh mass of acclimatized plants. We established conditions for in vitro cultivation and acclimatization for efficient propagation of V. flammea with a view towards conservation of the species or reestablishment of natural populations.

Resumo Bromeliaceae é restrita à região neotropical, com alto grau de endemismo, que contribui para o aumento da biodiversidade, devido às características morfológicas dos indivíduos. Objetivando desenvolver uma tecnologia in vitro de conservação para obtenção de plantas com vistas à reintrodução, sementes de Vriesea flammea L.B.Sm. foram coletadas, esterilizadas, germinadas em meio de cultura e as plantas obtidas foram cultivadas por 180 dias em meio MS com diferentes concentrações de nutrientes minerais (25 e 50% dos sais nitrogenados e dos macronutrientes), bem como em diferentes concentrações de sacarose (20, 30, 40, 50 e 60 g L-1). Após, as plantas foram aclimatizadas por 150 dias em substrato comercial. Quando da esterilização das sementes, apenas 4% destas contaminaram. Por sua vez, a esterilização de cápsulas resultou em 43,6% de sementes contaminadas. Taxas de germinação superiores a 80% foram registradas. Baixas concentrações dos sais nitrogenados e de macronutrientes proporcionaram sobrevivência superior a 76% e promoveram maior desenvolvimento das plantas in vitro do que o meio MS completo. O desenvolvimento do sistema aéreo, radicular, a massa fresca e pigmentos fotossintéticos apresentaram relação positiva com a concentração de sacarose in vitro. A maior concentração de sacarose também propiciou indiretamente maior desenvolvimento do sistema aéreo e massa fresca das plantas aclimatizadas. Estabelecemos as condições de cultivo in vitro e aclimatização para a eficiente propagação de V. flammea com vistas à conservação da espécie ou reestabelecimento das populações naturais.

Influence of edge in the structure of the vegetation of an open ombrophilous forest in Alagoas / Influência da borda na estrutura da vegetação de uma floresta ombrófila aberta em Alagoas

Understanding the influence of fragmentation on the behavior of forest essential elements in different vegetation formations is fundamental for the definition of conservation strategies. In this study, the aim was to evaluate the influence of the edge environment on the phytosociological structure of a fragment of Open Ombrophylous Forest, in Rio Largo, Alagoas. Five transects of 10.0 x 100.0 m were subdivided into ten 10.0 x 10.0 m plots to collect the data. All tree individuals with Chest Height Circumference ≥ 15 cm were sampled, measured and later identified in the herbarium of the Institute of the Environment of Alagoas. For the analysis, the phytosociological parameters Shannon-Wiener diversity (H'), Pielou equability (J') were calculated after defined the successional classes and dispersion syndromes of the species sampled. The edge effect was analyzed by comparing the richness, diversity, equability and number of individuals in the interior and at the edge of the fragment, using the Venn diagram technique. There were 581 arboreal individuals, of which 434 were identified as belonging to 20 families, 24 genera and 30 morphospecies. Among the raised species, there were higher occurrences of early secondary (46.67%) and late (23.33%), as well as those of zoocoric dispersion (53.33%). The diversity was 2.89 nats/ind., and the Pielou (J') equability was 0.8497. The edge environment did not influence the establishment of species. This may have occurred due to the environmental characteristics of the open ombrophylous forest.

Compreender a influência da fragmentação sobre o comportamento das essências florestais em diferentes formações vegetacionais é fundamental para que se possa definir estratégias de conservação. Neste trabalho,objetivou-se de avaliar a influência do ambiente de borda sobre estrutura fitossociológica de um fragmento de Floresta Ombrófila Aberta, em Rio Largo, Alagoas. Para a coleta dos dados foram alocados cinco transectos de 10,0 x 100,0 m, subdivididos em dez parcelas de 10,0 x 10,0 m. Foram amostrados todos osindivíduos arbóreos com Circunferência à Altura do Peito ≥ 15 cm, que foram mensurados e posteriormente identificados no herbário do Instituto do Meio Ambiente de Alagoas. Para a análise foram calculados osparâmetros fitossociológicos, a diversidade de Shannon-Wiener (H'), a equabilidade de Pielou (J'), definidas as classes sucessionais e síndromes de dispersão das espécies amostradas. O efeito de borda foi analisado por meio de comparação da riqueza, diversidade, equabilidade e número de indivíduos no interior e na borda do fragmento, empregando-se a técnica diagrama de Venn. Foram registrados 581 indivíduos arbóreos, dos quais 434 foram identificados como pertencentes a 20 famílias, 24 gêneros e 30 morfoespécies. Entre as espécies levantadas, houve maior ocorrência de secundárias iniciais (46,67%) e tardias (23,33%), assim como de dispersão zoocórica (53,33%). A diversidade foi de 2,89 nats/ind., e a equabilidade de Pielou (J') foi de 0,8497. O ambiente de borda não influenciou no estabelecimento de espécies. Isso pode ter ocorrido em virtude das características da floresta ombrófila aberta.

Multiple Effect of Different Plant Growth Promoting Microorganisms on Beans (Phaseolus vulgaris L. ) Crop

Abstract We evaluated the effect of combined Rhizobium tropici, Trichoderma asperellum and plant growth-promoting rhizobacteria (PGPR) in beans crop. The hypothesis that strains of T. asperullum, R. tropici and PGPR combined could improve growth, biomass accumulation and beans yield was tested under greenhouse and field conditions. The treatments consisted of control, mineral nitrogen application and inoculation, isolated and associated with the following microorganisms: Rhizobium tropici, Bacillus subtilis, Trichoderma asperellum and Burkholderia sp. 10N6. Results were evaluated by shoot dry weight (SDW) and root dry weight (RDW), number of nodules and yield components. In greenhouse environment all the microorganisms behaved similarly, and the treatments inoculated with Burkholderia sp. 10N6 (IBu) and R. tropici (IR) stood out regarding the production components. In field conditions the treatments IR and IRTBa presented the highest values of SDW and RDW. Our results suggest that inoculation with R. tropici, T. asperellum and PGPR may promote beans growth and bring benefits to shoot and root accumulation, increase the number of nodules as well as improve yield components, contributing to a sustainable agriculture.

Principales reguladores hormonales y sus interacciones en el crecimiento vegetal / Main hormonal regulators and their interactions in plant growth

Resumen Una hormona vegetal o fitohormona es un compuesto producido internamente por una planta, que ejerce su función en muy bajas concentraciones y cuyo principal efecto se produce a nivel celular, cambiando los patrones de crecimiento de los vegetales y permitiendo su control. Los reguladores vegetales son compuestos sintetizados químicamente u obtenidos de otros organismos y son, en general, mucho más potentes que los análogos naturales. Es necesario tener en cuenta aspectos críticos como oportunidad de aplicación, dosis, sensibilidad de la variedad, condición de la planta, etc., ya que cada planta requerirá de unas condiciones específicas de crecimiento que pueden afectarse por la concentración de ellos en el medio. Los reguladores vegetales son productos sintéticos que se han convertido en las primeras herramientas capaces de controlar el crecimiento y actividad bioquímica de las plantas por lo que su uso ha aumentado en los últimos años. Esta revisión busca hacer una recopilación bibliográfica de los primeros acontecimientos de la aplicación de los reguladores de crecimiento vegetal. Se presentan las principales características fisiológicas que pueden desarrollar la aplicación de estos sobre el crecimiento vegetal a nivel celular y su repercusión a nivel fenotípico; además, se describen las principales fitohormonas más conocidas en la aplicación biotecnológica. Entre ellas se encuentran auxinas, giberelinas, citoquininas, ácido abscísico, ácido salicílico, poliaminas, jasmonatos y derivados, brasinoesteroides, etileno y estrigolactonas. Se detallan las principales funciones a nivel del metabolismo vegetal y sus posibles interacciones intra e intercelular.

Abstract A vegetal hormone or phytohormone is a compound produced inside by a plant, that work in low concentrations and whose mainly effect occurs at the cellular level, changing the patterns of grow in vegetal organism and allow their control. The plant grows regulators are synthetic chemical compounds that can be obtained by the organism different to the plants and are more stronger that natural analogues, is necessary have in consideration different aspects like application opportunity, concentration, sensibility, plant condition, it's because every plant requires specific conditions of grow that can be affected by phytohormonal concentration in the soil or medium. The vegetal regulators are synthetic products that it has been converted in the mainly tool available to control the growing and biochemical activity of the plant and for that reason their use are increased in the last years. This review makes a bibliography compilation of the first events in the beginning of vegetal plant regulators application and presents the mainly physiologic characteristics that can be developed by application of vegetal hormones and their action in cellular and phenotypic response, furthermore we explain some of the mechanisms of action of the mainly ten phytohormones more knowledge in the biotechnological application: auxins, gibberellins, cytokinins, abscisic acid, salicylic acid, polyamines, jasmonates and derived compounds, brassinosteroids, ethylene, and strigolactones. We describe their mainly functions to vegetal metabolism and their possible interactions intracellular and extracellular.

Kinetics and modeling of cell growth for potential anthocyanin induction in cultures of Taraxacum officinale G.H. Weber ex Wiggers (Dandelion) in vitro

Background: Taraxacum officinale G.H. Weber ex Wiggers is a wild plant used in folk medicine to treat several diseases owing to bioactive secondary metabolites present in its tissue. The accumulation of such molecules in plant cells can occur as a response against abiotic stress, but these metabolites are often deposited in low concentrations. For this reason, the use of a biotechnological approach to improve the yields of technologically interesting bioactive compounds such as anthocyanins is a compelling option. This work focuses on investigating the potential of in vitro T. officinale cultures as an anthocyanin source. Results: To demonstrate the suitability of anthocyanin induction and accumulation in calluses under specific conditions, anthocyanin was induced in the T. officinale callus. A specific medium of 5.5% sucrose supplemented with 6-benzylaminopurine /1-naphthaleneacetic acid in a 10:1 ratio was used to produce an anthocyanin yield of 1.23 mg g-1 fw. An in vitro dandelion callus line was established from this experiment. Five mathematical models were then used to objectively and predictably explain the growth of anthocyanin-induced calluses from T. officinale. Of these models, the Richards model offered the most suitable representation of anthocyanin callus growth in a solid medium and permitted the calculation of the corresponding kinetic parameters. Conclusions: The findings demonstrate the potential of an in vitro anthocyanin-induced callus line from T. officinale as an industrial anthocyanin source.

Growth and symptoms of deficiency of micronutrients in young plants of jute / Crescimento e sintomas de deficiência de micronutrientes em plantas jovens de juta

The knowledge of micronutrients for Jute (Corchorus capsularis L.) plants might be a valuable tool to the subsidize taking of decisions to the management of such species. The objective of this study was to describe the symptoms of micronutrient deficiencies in jute plants and to analyze micronutrient contents in leaves, stems, and roots. The experiment was carried out in a greenhouse, with six treatments and four replications in a randomized block design. The treatments were, as follows: Complete solution (C) and solution with the omission of the following nutrients: B, Cu, Fe, Mn, and Zn. Except for Cu deficiency, the morphological alterations were easily characterized for all nutrients evaluated, in which Fe and Zn were the first and the last to cause symptoms in plants, respectively. In general, the nutrients that were most limiting to the growth of Jute plant and for dry mass were Fe and B. The omission of B, Mn and Fe limited root growth while the Zn and Cu deficiencies limited the growth of the aerial part. The nutrient contents were ordered as it follows: Fe> Mn> Zn> B> Cu in the leaves, Fe> Mn> B> Zn> Cu in the stem and Fe> Zn> Mn> B> Cu in the roots. For seedings of Jute, the deficiency of Fe and B are the most limiting and the suitable nutritional contents for those seedlings are 11.37; 8.99; 346.14; 248.88 and 77,28 mg.kg-1 for B, Cu, Fe, Mn and Zn in the leaves, respectively.

O conhecimento acerca de micronutrientes em plantas de juta (Corchorus capsularis L.) pode ser uma importante ferramenta para subsidiar tomadas de decisão quanto ao manejo de tal espécie. O objetivo do presente estudo foi descrever os sintomas de deficiência de micronutrientes em plantas de juta e analisar o teor de micronutrientes contidos em folhas, caules e raízes. O experimento foi conduzido em casa de vegetação, com seis tratamentos e quatro repetições para cada tratamento em delineamento em blocos ao acaso. Os tratamentos foram: solução completa (C) e solução com a omissão dos seguintes nutrientes: B, Cu, Fe, Mn e Zn. Com exceção da deficiência de Cu, as alterações morfológicas foram fáceis de caracterizar para todos os nutrientes analisados, com Fe e Zn sendo o primeiro e o último a causar sintomas em plantas, respectivamente. Em geral, os nutrientes que foram os mais limitantes para o crescimento e matéria seca de juta foram Fe e B. A omissão de B, Mn e Fe limitou o crescimento radicular, enquanto que a deficiência de Zn e Culimitou o crescimento da parte aérea. O teor de nutrientes seguiu a seguinte ordem decrescente: Fe> Mn> Zn> B> Cu nas folhas, Fe> Mn> B> Zn> Cu no caule e Fe> Zn> Mn> B> Cu nas raízes. Pra mudas de juta, a deficiência de Fe e B são as mais limitantes e os teores nutricionais adequados para estas mudas são 11,37; 8.99; 346.14; 248.88; and 77.28 mg.kg-1, respectivamente, para B, Cu, Fe, Mn and Zn nas folhas.

Archaea diversity in vegetation gradients from the Brazilian Cerrado

Abstract We used 16S rRNA sequencing to assess the archaeal communities across a gradient of Cerrado. The archaeal communities differed across the gradient. Crenarcheota was the most abundant phyla, with Nitrosphaerales and NRPJ as the predominant classes. Euryachaeota was also found across the Cerrado gradient, including the classes Metanocellales and Methanomassiliicoccaceae.

JcZFP8, a C2H2 zinc finger protein gene from Jatropha curcas, influences plant development in transgenic tobacco

Background: Jatropha curcas L., as an important strategic biofuel resource with considerable economic potential, has attracted worldwide attention. However, J. curcas has yet to be domesticated. Plant height, an important agronomic trait of J. curcas, has not been sufficiently improved, and the genetic regulation of this trait in J. curcas is not fully understood. Zinc finger proteins (ZFPs), a class of transcription factors, have previously been shown to play critical roles in regulating multiple aspects of plant growth and development and may accordingly be implicated in the genetic regulation of plant height in J. curcas. Results: In this study, we cloned JcZFP8, a C2H2 ZFP gene in J. curcas. We found that the JcZFP8 protein was localized in the nucleus and contained a conserved QALGGH motif in its C2H2 structure. Furthermore, ectopic expression of JcZFP8 under the control of the 35S promoter in transgenic tobacco resulted in dwarf plants with malformed leaves. However, when JcZFP8 was knocked out, the transgenic tobacco did not show the dwarf phenotype. After treatment with the gibberellic acid (GA) biosynthesis inhibitor paclobutrazol (PAC), the dwarf phenotype was more severe than plants that did not receive the PAC treatment, whereas application of exogenous gibberellin3 (GA3) reduced the dwarf phenotype in transgenic plants. Conclusions: The results of this study indicate that JcZFP8 may play a role in J. curcas plant phenotype through GA-related pathways. Our findings may help us to understand the genetic regulation of plant development in J. curcas and to accelerate breeding progress through engineering of the GA metabolic pathway in this plant. How to cite: Shi X,Wu Y, Dai T, et al. JcZFP8, a C2H2 zinc-finger protein gene from Jatropha curcas, influences plant development in transgenic tobacco.

Evaluation of root-knot nematode disease control and plant growth promotion potential of biofertilizer Ning shield on Trichosanthes kirilowii in the field

Abstract Biofertilizer Ning shield was composed of different strains of plant growth promotion bacteria. In this study, the plant growth promotion and root-knot nematode disease control potential on Trichosanthes kirilowii in the field were evaluated. The application of Ning shield significantly reduced the diseases severity caused by Meloidogyne incognita, the biocontrol efficacy could reached up to 51.08%. Ning shield could also promote the growth of T. kirilowii in the field by increasing seedling emergence, height and the root weight. The results showed that the Ning shield could enhance the production yield up to 36.26%. Ning shield could also promote the plant growth by increasing the contents of available nitrogen, phosphorus, potassium and organic matter, and increasing the contents of leaf chlorophyll and carotenoid pigment. Moreover, Ning shield could efficiently enhance the medicinal compositions of Trichosanthes, referring to the polysaccharides and trichosanthin. Therefore, Ning shield is a promising biofertilizer, which can offer beneficial effects to T. kirilowii growers, including the plant growth promotion, the biological control of root-knot disease and enhancement of the yield and the medicinal quality.