Application of strigolactone analogs in storage of Gastrodia elata / 中国中药杂志

This study explored the preservation effect of strigolactone analogs on Gastrodia elata tubers and screened out the suitable preservation measures of G. elata to provide a safer and more effective method for its storage and preservation. Fresh G. elata tubers were treated with 7FGR24, 2,4-D isooctyl ester, and maleic hydrazide, respectively. The growth of flower buds, the activities of CAT, and MDA, and the content of gastrodin and p-hydroxybenzyl alcohol were measured to compare the effects of different compounds on the storage and preservation of G. elata. The effects of different storage temperatures on the preservation of 7FGR24 were compared and analyzed. The gibberellin signal transduction receptor gene GeGID1 was cloned, and the effect of 7FGR24 on the expression level of GeGID1 was analyzed by quantitative polymerase chain reaction(qPCR). The toxicity of the G. elata preservative 7FGR24 was analyzed by intragastric administration in mice to evaluate its safety. The results showed that compared with 2,4-D isooctyl ester and maleic hydrazide, 7FGR24 treatment had a significant inhibitory effect on the growth of G. elata flower buds, and the CAT enzyme activity of G. elata was the highest, indicating that its preservation effect was stronger. Different storage temperatures had different effects on the preservation of G. elata, and the preservation effect was the strongest at 5 ℃. The open reading frame(ORF) of GeGID1 gene was 936 bp in length, and its expression level was significantly down-regulated after 7FGR24 treatment, indicating that 7FGR24 may inhibit the growth of flower buds by inhibiting the gibberellin signal of G. elata, thereby exerting a fresh-keeping effect. Feeding preservative 7FGR24 had no significant effect on the behavior and physiology of mice, indicating that it had no obvious toxicity. This study explored the application of the strigolactone analog 7FGR24 in the storage and preservation of G. elata and preliminarily established a method for the storage and preservation of G. elata, laying a foundation for the molecular mechanism of 7FGR24 in the storage and preservation of G. elata.

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.

Use of plant growth regulators in fig tree seedling s 'roxo de valinhos' / Uso de reguladores vegetais em mudas de figueira 'Roxo de Valinhos'

The application of plant growth regulators can promote better development of the seedlings, essential for the success of fruit growing. The current study aims to evaluate the use of plant growth regulators in fig tree seedlings 'Roxo de Valinhos'. The experiment was carried out in a suspended nursery covered with plastic, using rooted cuttings of the cultivar Roxo de Valinhos. Four applications were made with a commercial product, known as Stimulate®, at doses of 0, 50, 100, 150, and 200 mL L-1. Using a randomized block experimental design, the study was subdivided into plots (doses X days of the last application [after 0, 7, 14 and 21]). The following traits were evaluated: stem and root length; stem diameter; root volume; leaf number; leaf area; stem, leaf and root dry mass; specific leaf area, leaf weight ratio; leaf area ratio; and chlorophyll total. Results indicated that the product promoted greater seedlings development at a dose range from 100 to 150 mL L-1. Different dose levels did not vary according to the days after product application. Furthermore, using such technique enabled seedlings of higher quality and vigour.

A aplicação de reguladores vegetais pode configurar uma técnica viável para promoção do melhor desenvolvimento das mudas, imprescindível para o sucesso da fruticultura. Deste modo, objetivou-se avaliar o uso de reguladores vegetais na produção de mudas da figueira 'Roxo de Valinhos'. O experimento foi realizado em viveiro suspenso com cobertura plástica, utilizando-se estacas enraizadas da cultivar Roxo de Valinhos. Foram realizadas quatro aplicações com o produto comercial Stimulate® nas concentrações de 0, 50, 100, 150, e 200 mL L-1. Utilizou-se o delineamento experimental em blocos casualizados com parcelas subdivididas [concentrações X épocas de avaliação (após 0, 7, 14 e 21 dias da última aplicação)]. Avaliou-se: comprimento do ramo e da maior raiz; diâmetro do ramo; volume de raízes; número de folhas e área foliar; massa seca de folhas, ramos e raízes; área específica foliar, razão de peso foliar e razão da área foliar; e teores de clorofila total. O uso do produto, nas concentrações de 100 a 150 mL L-1, promoveu maior desenvolvimento das mudas. O efeito das diferentes doses não variou em função dos dias após aplicação do produto. O uso de tal técnica permite a obtenção de mudas de maior qualidade e vigor.

Genome-wide identification and expression analysis of gibberellin biosynthesis, metabolism and signaling family genes in Phyllostachys edulis / 生物工程学报

Gibberellin is an essential plant hormone that plays an important regulatory role throughout the life cycle of higher plants. A total of 23 genes involved in gibberellin action were identified from Phyllostachys edulis genome, including 8 GA20ox and 1 GA3ox genes involved in the gibberellin biosynthesis, 8 GA2ox genes involved in the metabolism of gibberellin, 2 GID1 genes involved in gibberellin perception, 2 GID2 genes and 2 DELLA genes involved in gibberellin signal transduction. Phylogenetic analysis of these genes from Arabidopsis, Oryza sativa and Phyllostachys edulis revealed that gibberellin biosynthesis, metabolism, and signaling pathways are conserved in these species. Treatment of seeds and seedlings of bamboo with exogenous gibberellin revealed that gibberellin significantly increased seed germination rate and stem elongation of seedlings, and had the best concentration of action. The expression levels of GA20ox and GA3ox genes in the bamboo seedlings were down-regulated and the expression of the active gibberellin-degrading gene GA2ox was up-regulated after GA3 treatment, and the transcriptional level of the gibberellin receptor GID1 and the positive regulatory gene GID2 was significantly increased while the expression of the negative regulatory gene DELLA was decreased. These genes have significant differences in the expression of different spatial locations of bamboo shoot stems, GA20ox, GA3ox, GA2ox, GID1 and GID2 are all expressed in the upper part of bamboo shoots, while the repressor gene DELLA accumulates at the bottom of the shoots and is hardly expressed at the top.

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.

Kernel size and weight affected by three plant bioregulators applied at bloom to Non Pareil and Carmel almond cultivars

Background: The yield of almonds [Prunus dulcis (Mill.) D.A. Webb] could be low due to climatic problems and any factor improving kernel size and weight, such as the use of plant bioregulators (PBRs), should be beneficial. Results: Three plant bioregulators: 24-epibrassinolide (BL), gibberellic acid (GA3) and kinetin (KN) were applied at three spray concentrations to Non Pareil and Carmel cultivars, at two phenological stages during bloom, in the 2014 and 2015 seasons. The results showed significant differences (P b 0.0001). For total dry weight of Non Pareil, the best treatment was BL (30 mg·L-1), with an average of 1.45 g, while the control was 1.30 g, at pink button during 2015. For Carmel, the best dry weight was 1.23 g, achieved with BL (30 mg·L-1) at fallen petals in both seasons. The average dry weight of the controls varied between 1.13 and 1.18 g. The greatest almond lengths and widths in Non Pareil were 24.98 mm and 15.05 mm, achieved with BL (30 mg·L-1) and KN (50 µL·L-1) treatments, respectively, applied at pink button in 2015. In Carmel, the greatest length and width were 24.38 and 13.44 mm, obtained with BL (30 mg·L-1) applied at the stages of pink button and fallen petals, respectively, in 2015. The control reached lengths between 22.33 and 23.38 mm, and widths between 11.99 and 12.93 mm. Conclusions: The use of the bioregulators showed significant favorable effects on dry weight, length and width of kernels at harvest, in both cultivars.

Influence of gibberellic acid, indole butyric acid, and methanol on morpho-physiological and phytochemical traits in Thymus vulgaris L.

Background: Plant growth regulators [PGRs] have important roles in many processes such as germination, seedling growth, nutrition uptake, morphogenesis, ripening, etc

Objective: This study aimed to evaluate the effect of gibberellic acid, indole butyric acid, and methanol as plant growth regulators on morpho-physiological and phytochemical features in Thymus vulgaris L

Methods: The farm experiment based on a randomized complete block design was performed at 2014. The treatments were included G1M1 [GA3 50 ppm + methanol 20 %], G1M2 [GA3 50 ppm +methanol 40 %], G2M1 [GA3 100 ppm + methanol 20 %], G2M2 [GA3 100 ppm + methanol 40 %], I1M1 [IBA 50 ppm + methanol 20 %], I1M2 [IBA 50 ppm + methanol 40 %], I2M1 [IBA 100 ppm + methanol 20 %], I2M2 [IBA 100 ppm + methanol 40 %], G1I2M2 [GA3 50 ppm + IBA 100 ppm + methanol 40 %], G1I2M2 [GA3 100 ppm + IBA 50 ppm + methanol 40 %], and control [distillate water]

Results: The results showed that the combination of GA3 or IBA along with methanol changed significantly leaf length and width, number of branches, leaf dry weight, stem dry weight, plant dry weight, seed weight, essential oil content and thymol amount. The highest values of the most traits were observed in I1M1 treatment

Conclusion: Methanol combination with one of the GA3 or IBA can improve morpho-physiological and phytochemical traits of thyme [Thymus vulgaris L.]. Thus, the most effective PGRs combination was related to GA3 50 ppm + Methanol 20 % and IBA 50 ppm + Methanol 20 %

Plant growth regulators and shade on emergence in macadamia nut tree / Reguladores vegetais e sombreamento na emergência de plântulas de macadâmia

This study aimed to evaluate the effect of plant growth regulators and shading on seed germination of macadamia nut trees. The experiment was conducted in a seedling production nursery of the company "QueenNut Macadâmia" located in the "Palmeiras" Farm, Dois Córregos, São Paulo (SP) state, Brazil. The Treatments were T1: water (control) under a shading screen, T2: GA4+7 + N-(phenylmethyl)-aminopurine (Promalin®) at 200 mL L-1 under a shading screen, T3: Promalin® at 400 mL L-1 under a shading screen, T4: gibberellic acid (GA3) + kinetin (Kt) + 3- indolebutyric acid (IBA) ­ Stimulate® at 5 mL kg-1 seeds under a shading screen, T5: Stimulate® at 10 mL kg-1 of seeds under a shading screen, and T6: water (control) under no shading screen. Seeds were soaked in the solutions or in water containing plant growth regulators for 24 hours. Then, they were dried and sown in sand. 450 seeds were used for each treatment. The evaluations began from seedling emergence by counting the total number of seedlings per treatment. A high average of macadamia nut tree seedling emergence was obtained in the treatments GA4+7 + N-(phenylmethyl)-aminopurine (Promalin®) 400 mL L-1 with Sombrite® (75.7%), GA4+7 + N-(phenylmethyl)-aminopurine (Promalin®) 200 mL L-1 (72.6%) Sombrite® and water (control) without Sombrite® (71.5%).

Este estudo objetivou avaliar os efeitos de reguladores vegetais e sombreamento na emergência de plântulas de macadâmia. O experimento foi conduzido no viveiro de produção de mudas de macadâmia da empresa QueenNut Macadâmia, na Fazenda Palmeiras no município de Dois Córregos-SP. Os tratamentos utilizados foram: T1. água (testemunha) com Sombrite®, T2. GA4+7 + N-(fenilmetil)-aminopurina (Promalin®) a 200 mL L-1 com Sombrite®, T3. Promalin® a 400 mL L-1 com Sombrite®, T4. GA3 + IBA + Kt ­ Stimulate® a 5 mL kg-1 sementes com Sombrite®, T5. Stimulate® a 10 mL kg-1 sementes com Sombrite® e T6. água (testemunha) sem Sombrite®. As sementes foram embebidas em água ou nas soluções contendo os reguladores vegetais durante 24h, secas à sombra e semeadas em sementeiras de areia. Foram utilizadas 450 sementes em cada tratamento. A partir da emergência das plântulas foram iniciadas as avaliações, realizadas através da contagem do número total de plântulas emergidas por tratamento. Os melhores resultados na emergência de plântulas de macadâmia foram obtidos nos tratamentos com GA4+7 + N-(fenilmetil)- aminopurina (Promalin®) a 400 mL L-1 com Sombrite® (75,7%), GA4+7 + N-(fenilmetil)-aminopurina (Promalin®) a 200 mL L-1 (72,6%) com Sombrite® e água (testemunha) sem Sombrite® (71,5%).

Avaliação dos fitorreguladores auxina e giberelina na germinação e crescimento do arroz / Assessment of auxin and gibberellin on rice germination and growth / Evaluación de fitorreguladores auxina y giberelina en la germinación y crecimiento del arroz

O arroz (Oryza sativa L.) é uma planta da família das Poaceas (gramíneas), sendo um dos cereais mais cultivados no mundo. Os fitorreguladores como auxina e giberilina podem influenciar o crescimento e desenvolvimento das plantas como o arroz. O objetivo deste estudo foi avaliar a germinação e o crescimento do arroz sob diferentes doses de fitorreguladores (auxina e giberelina). Foram conduzidos dois experimentos, o primeiro para determinar a germinação e comprimento radicular das sementes de arroz. O segundo experimento foi conduzido para determinar a altura, massa seca da parte área (MSPA) e o conteúdo nitrogênio (N) da parte aérea (NPA). Nos dois experimentos foram testadas quatro doses de auxina + giberelina: 0 (testemunha); 200; 500 e 1000 mL ha­1. O delineamento experimental foi inteiramente casualizado com cinco repetições para cada tratamento nos dois experimentos. A germinação das sementes e o comprimento radicular foram aumentados com a aplicação de auxina e giberelina. A altura e o NPA foram aumentados significantemente com a aplicação de auxina e giberelina. Concluiu-se que a aplicação de auxina e giberelina na cultura do arroz aumentaram a germinação e o comprimento radicular das sementes. Além disso, aumentou a altura e o conteúdo de nitrogênio nas plantas de arroz.

Rice (Oryza sativa L.) is one of the most widely grown cereals in the world. Phytoregulators such as auxin and gibberellin can influence both growth and development of plants such as rice. The aim of this study was to assess the germination and growth of rice under different doses of phytoregulators (auxin and gibberellin). Two experiments were performed, one to determine the germination and root length of rice seeds, and the second one to evaluated height, shoot dry mass (SDM) and shoot nitrogen content (SNC). Both experiments tested four doses of auxin + gibberellin (0 (control), 200, 500 and 1000 mL ha-1). The experimental design was completely randomized with five repetitions for both experiments. The germination and root length of rice seedlings were increased by the application of auxin and gibberellin. Rice height and SNC were significantly increased with the application of auxin and gibberellin. Thus, it can be concluded that the application of auxin and gibberellin in rice increases germination, root length, plant height and nitrogen content.

El arroz (Oryza sativa L.) es una planta de la familia Poaceas (gramíneas), siendo uno de los cereales más cultivados en el mundo. Los fitorreguladores como auxina y giberelina pueden influir en el crecimiento y desarrollo de plantas, como el arroz. El objetivo de este estudio ha sido evaluar la germinación y el crecimiento del arroz bajo diferentes dosis de fitorreguladores (auxina y giberelina). Se realizaron dos experimentos, el primero para determinar la germinación y longitud de la raíz de las semillas de arroz. Se llevó a cabo un segundo experimento para determinar la altura, masa seca de la parte aérea (MSPA) y el contenido de nitrógeno (N) de la parte aérea (NPA). En ambos experimentos, se ensayaron cuatro dosis de auxina + giberelina: 0 (testigo); 200; 500 y 1000mL ha-1. El diseño experimental fue completamente al azar con cinco repeticiones para cada tratamiento en ambos experimentos. La germinación de las semillas y la longitud de la raíz se incrementaron mediante la aplicación de auxina y giberelina. La altura y el NPA se incrementaron de manera significativa mediante la aplicación de auxina y giberelina. Se concluye que la aplicación de auxina y giberelina en el cultivo de arroz incrementa la germinación y longitud de la raíz de las semillas. Además, incrementó la altura de plantas de arroz con nitrógeno.

In vitro propagation of the Garden Heliotrope, Valeriana officinalis L.: Influence of pre-chilling and light on seed germination.

Valeriana officinalis is an important medicinal herb commonly found in Kashmir valley. This study forms an important preliminary step for in-vitro micro propagation of V. officinalis from breaking the seed dormancy, inducing rapid seed germination and its subsequent micro propagation. We investigated the influence of pretreatment of V. officinalis seeds with reduced temperature and light on seed germination and in-vitro propagation. Culture of explants from cultivated seeds have demonstrated its potential for in vitro propagation and plantlet regeneration. Individual as well as combinations of treatments such as temperature and light availability influenced the germination of seeds variedly. Unchilled seeds of V. officinalis were given dip in GA3 (200 ppm) for 24, 48 and 120 h. Seeds treated with GA3 for 24 h and kept in darkness showed the best results, i.e. 48%. Seeds pretreated with GA3 for 120 h and incubated in dark showed 40% germination. Pre-chilling up to 72 h and kept in light showed maximum germination of 60% followed by 40% kept in darkness. Pre-chilling for 48 h resulted in 40 and 25% seed germination in light and darkness, respectively. GA3 pre-treatment for 72 h and 24 h pre chilling were most effective in inducing seed germination. Maximum shoot response was obtained on MS enriched with BAP (1mg/L) + IAA (0.1mg/L) combinations using shoot tips as explants. Multiple shoot regeneration from shoot apices was recorded on BAP (1mg/L) and BAP (1mg/L) + IAA (0.1mg/L).

Aspergillus clavatus Y2H0002 as a New Endophytic Fungal Strain Producing Gibberellins Isolated from Nymphoides pe ltata in Fresh Water

Eighteen endophytic fungi with different colony morphologies were isolated from the roots of Nymphoides peltata growing in the Dalsung wetland. The fungal culture filtrates of the endophytic fungi were treated to Waito-c rice seedling to evaluate their plant growth-promoting activities. Culture filtrate of Y2H0002 fungal strain promoted the growth of the Waito-c rice seedlings. This strain was identified on the basis of sequences of the partial internal transcribed spacer region and the partial beta-tubulin gene. Upon chromatographic analysis of the culture filtrate of Y2H0002 strain, the gibberellins (GAs: GA1, GA3, and GA4) were detected and quantified. Molecular and morphological studies identified the Y2H0002 strain as belonging to Aspergillus clavatus. These results indicated that A. clavatus improves the growth of plants and produces various GAs, and may participate in the growth of plants under diverse environmental conditions.

Diversity and Plant Growth Promoting Capacity of Endophytic Fungi Associated with Halophytic Plants from the West Coast of Korea

Five halophytic plant species, Suaeda maritima, Limonium tetragonum, Suaeda australis, Phragmites australis, and Suaeda glauca Bunge, which are native to the Muan salt marsh of South Korea, were examined for fungal endophytes by sequencing the internal transcribed spacer (ITS) region containing ITS1, 5.8S rRNA, and ITS2. In total, 160 endophytic fungal strains were isolated and identified from the roots of the 5 plant species. Taxonomically, all 160 strains belonged to the phyla Ascomycota, Basidiomycota, and Zygomycota. The most dominant genus was Fusarium, followed by the genera Penicillium and Alternaria. Subsequently, using 5 statistical methods, the diversity indices of the endophytes were determined at genus level. Among these halophytic plants, P. australis was found to host the greatest diversity of endophytic fungi. Culture filtrates of endophytic fungi were treated to Waito-C rice seedlings for plant growth-promoting effects. The fungal strain Su-3-4-3 isolated from S. glauca Bunge provide the maximum plant length (20.1 cm) in comparison with wild-type Gibberella fujikuroi (19.6 cm). Consequently, chromatographic analysis of the culture filtrate of Su-3-4-3 showed the presence of physiologically active gibberellins, GA(1) (0.465 ng/mL), GA(3) (1.808 ng/mL) along with other physiologically inactive GA(9) (0.054 ng/mL) and GA(24) (0.044 ng/mL). The fungal isolate Su-3-4-3 was identified as Talaromyces pinophilus.

Large scale propagation of an exotic edible bamboo, Phyllostachys pubescens Mazel ex H. De Lehale (Moso Bamboo) using seeds.

For ex vitro propagation, seeds of P.pubescens were treated with different concentrations of gibberellic acid (GA3) and germination of seeds was tested both in plastic pots as well as by direct sowing in the nursery beds. Maximum seed germination was achieved when treated with 200 mgL–1 (w/v) GA3. For in vitro propagation, an exposure of nodal explants from in vitro raised seedlings to 0.2 mgL–1 1–phenyl–3–(1,2,3–thiadiazol–5–yl) urea and 1 mgL–1 kinetin supplemented medium for 30 days and thereafter to hormone free Murashige and Skoog basal medium resulted in axillary shoot proliferation. For rooting, in vitro raised shoots were exposed to MS medium containing 2 mgL–1 indole-3-butyric acid for 15 days and then shifted to hormone free medium. On an average, 2.8 shoots were obtained in 75% of the cultures within 4 weeks. Such in vitro raised plants were successfully hardened and shifted to field conditions.

Effects of hormone treatment, light and temperatures on sprouting characteristics of Bupleurum chinense / 中国中药杂志

Seeds of Bupleurum chinense cultivar, Zhongchai No. 1, were sowed in plastic pots which used the arable layer soil as the nursery bed and putted in the artificial climate incubator at various temperatures (15, 20, 25, 15-25 degrees C) and light (8,12 h) to germinate, respectively. The lower constant temperature (15 degrees ) and the higher constant temperature (25 "C) were not conducive to the sprouting characteristics of B. chinese. While they were able to enhance root activity to some extent; The seeding growth of B. chinese was significantly better in the variable temperature than correspondence in the constant temperature, significantly. The emergence speed, emergence index, vigor index and root activity of Bupleurum were improved under the 12 h of light-time, but the germination rate was not improved. The sprouting of Bupleurum's seeds could be improved to some extent by soaking with hormone, such as gibberellin, cytokinin, salicylic acid. Gibberellin promoted seeds' sprouting and seedings's root activity of Bupleurum, while salicylic acid increased the root activity of seeding. There is a significant influence of light, temperatures and hormone treatment on the germination of Zhongchai No. 1 seeds, and all three are remarkably interacted; It is beneficial to promote seed germination by the temperature (20 + 5) degrees C, lighting (8 h) and gibberellin concentration (10 x 10(-6)).

Reguladores de crescimento vegetal no cultivo in vitro de Mentha x Piperita L / Plant growth regulators on in vitro culture of Mentha x piperita L

A micropropagação é uma técnica muitas vezes indicada para a multiplicação em larga escala de plantas com propriedades medicinais. Dentre elas, destaca-se a hortelã-pimenta (Mentha x Piperita L.), cujo óleo essencial é utilizado no tratamento de transtornos digestivos e respiratórios. Para otimizar o protocolo de micropropagação dessa espécie são necessários estudos, principalmente quanto à suplementação do meio de cultura para garantir a produção massal in vitro e posterior extração do óleo essencial. Nesse contexto, objetivou-se avaliar o efeito de concentrações e combinações de reguladores de crescimento vegetal na morfogênese in vitro de hortelã-pimenta. Segmentos nodais provenientes de plântulas estabelecidas in vitro foram utilizados como fonte de explante e inoculados em meio de cultura MS suplementado com 0; 2,0 e 4,0 mg L-1 de BAP (6-benzilaminopurina), 0; 0,5 e 1,5 mg L-1 de ANA (ácido naftaleno-acético) e 0; 0,5 e 1,0 mg L-1 de GA3 (ácido giberélico). O delineamento experimental adotado foi inteiramente casualizado, com os tratamentos distribuídos em esquema fatorial 3x3x3 com oito repetições. Concluiu-se que o BAP favoreceu a sobrevivência de segmentos nodais de M. x Piperita inoculados in vitro e, quando combinado ao GA3, promoveu a brotação dos explantes. Essas características, no entanto, não foram estimuladas pela adição de ANA ao meio de cultura. Conclui-se que após a multiplicação dos brotos in vitro estes devem ser transferidos para meio sem reguladores para seu desenvolvimento. Apesar dos efeitos benéficos do BAP na organogênese de M. x Piperita, elevadas concentrações deste regulador de crescimento vegetal promoveram a formação de calos.

Micropropagation is a technique used for the large-scale production of medicinal plants. Among them, peppermint (Mentha x piperita L.) may be mentioned because of the pharmacological importance of its essential oil, which is used on the treatment of digestive and respiratory disorders. Studies are needed in order to optimize the micropropagation protocol of this species, especially concerning the culture medium, to ensure the in vitro mass clonal production and to enable the future extraction of the plant essential oil. Therefore, this work aimed to evaluate the effects of concentrations and combinations of different plant growth regulators on the in vitro morphogenesis of peppermint. Nodal segments from plantlets already established in vitro were used as explants and inoculated on MS medium supplemented with 0, 2.0 and 4.0 mg L-1 of BAP (6-benzylaminopurine), 0, 0.5 and 1.5 mg L-1 of NAA (naphthalene acetic acid) and 0; 0.5 and 1.0 mg L-1 of GA3 (gibberellic acid). The experiment was in a completely randomized design, set up as a 3x3x3 factorial design with eight replicates. We concluded that BAP increases the survival rate of in vitro inoculated nodal segments of M. x piperita. In addition, its combination with GA3 stimulates explants shooting. Those aspects, however, are not promoted by the addition of NAA into the culture medium. Also, the results indicate that, after in vitro multiplication, peppermint shoots must be transferred to another medium without plant growth regulators for shoot elongation. High concentrations of BAP promote calli induction, despite having beneficial effects on the organogenesis of M. piperita.

A novel combination of plant growth regulators for in vitro regeneration of complete plantlets of guar [Cyamopsis tetragonoloba (L.) Taub.].

A novel combination of plant growth regulators comprising indole-3-butyric acid (IBA), 6-benzylaminopurine (BA) and gibberellic acid (GA3) in Murashige and Skoog basal medium has been formulated for in vitro induction of both shoot and root in one culture using cotyledonary node explants of guar, (Cyamopsis tetragonoloba). Highest percentages of shoot (92%) and root (80%) induction were obtained in the medium containing (mg/L) 2 IBA, 3 BA and 1 GA3. Shoot regeneration from the cotyledonary node explants was observed after 10-15 days. Regeneration of roots from these shoots occurred after 20 to 25 days. The regenerated plantlets showed successful acclimatization on transfer to soil. This protocol is expected to be helpful in carrying out various in vitro manipulations in this economically and industrially important legume.

Carotenoid genes transcriptional regulation for astaxanthin accumulation in fresh water unicellular alga Haematococcus pluvialis by gibberellin A3 (GA3).

The fresh water unicellular alga Haematococcus pluvialis is a promising natural source of astaxanthin. The present study investigated the transcriptional expression of carotenoid genes for astaxanthin accumulation in H. pluvialis using real-time fluorescence quantitative PCR (qRT-PCR). With treatments of 20 and 40 mg/L of gibberllin A3 (GA3), five genes ipi-1, ipi-2, psy, pds and bkt2 were up-regulated with different expression profiles. GA20 (20 mg/L of GA3) treatment had a greater effect on transcriptional expression of bkt2 than on ipi-1 ipi-2, psy and pds (>4-fold up-regulation). However, GA40 (40 mg/L of GA3) induced more transcriptional expression of ipi-2, psy and bkt2 than both ipi-1 and pds. The expression of lyc, crtR-B and crtO for astaxanthin biosynthesis was not affected by GA3 in H. piuvialis. In the presence of GA3, astaxanthin biosynthesis genes of ipi-1, pds and bkt2 were up-regulated at transcriptional level, psy at post-transcriptional level, whereas ipi-2 was up-regulated at both levels. The study could potentially lead to a scale application of exogenous GA3 in astaxanthin production with H. pluvialis just like GAs perform in increasing crops production and it would provide new insight about the multifunctional roles of carotenogenesis in response to GA3.

Giberelina, citocinina e auxina na qualidade química de bagas de uva 'Superior Seedless' / Gibberellin, citocinin and auxin on chemical quality of 'Superior Seedless' grape berries

Os experimentos foram conduzidos no município de Juazeiro/BA com a finalidade de avaliar o efeito de reguladores vegetais compostos por giberelina, citocinina e auxina na qualidade química de bagas de uva do cultivar Superior Seedless. No primeiro ensaio estudaram-se os efeitos de Stimulate (biorregulador) e X-Cyte (citocinina) associado a uma nova formulação comercial de giberelina (N-Large) e ao Pro-Gibb, produto usualmente utilizado como fonte de giberelina, aplicados via pulverização na fase de desenvolvimento das bagas (18, 21, 51 e 56 dias após a poda de produção). Para tanto se empregou os seguintes tratamentos: T1: Pro-Gibb; T2: Stimulate (Dose 1); T3: Stimulate (Dose 2); T4: Stimulate (Dose 3); T5: Pro-Gibb + X-Cyte (Dose Baixa - DB); T6: Pro-Gibb + X-Cyte (Dose Média - DM); T7: Pro-Gibb + X-Cyte (Dose Alta - DA); T8: N-Large; T9: N-Large + X-Cyte (DB); T10: N-Large + X-Cyte (DM); T11: N-Large + X-Cyte (DA). O segundo ensaio teve por objetivo verificar o efeito da nova formulação de giberelina (N-Large) associada ou não a citocinina (X-Cyte) também aplicados via pulverização direcionada aos cachos na fase de desenvolvimento das bagas (17, 55 e 66 dias após a poda de produção). Assim, os seguintes tratamentos foram empregados: T1: Pro-Gibb; T2: N-Large (DB); T3: N-Large (DM); T4: N-Large (DA); T5: N-Large (DB) + X-Cyte (DB); T6: N-Large (DB) + X-Cyte (DM); T7: N-Large (DB) + X-Cyte (DA); T8: N-Large (DM) + X-Cyte (DB); T9: N-Large (DM) + X-Cyte (DM); T10: N-Large (DM) + X-Cyte (DA); T11: N-Large (DA) + X-Cyte (DB); T12: N-Large (DA) + X-Cyte (DM); T13: N-Large (DA) + X-Cyte (DA). O delineamento experimental foi em blocos ao acaso com quatro repetições, onde se considerou cada parcela uma repetição com três plantas úteis na mesma linha de plantas. Por ocasião da colheita, momento em que a média dos cachos apresentava teor de sólidos solúveis superior a 15 ºBrix, foram retiradas bagas para as análises de sólidos solúveis, pH, acidez titulável e, cálculo do ratio (SS/AT). Em ambos os ensaios os reguladores vegetais avaliados não proporcionaram alterações significativas nas características químicas das bagas de uva 'Superior Seedless'. Assim, a ausência de diferença de resposta entre o produto comercialmente empregado (Pro-Gibb) e os demais testados (Stimulate, X-Cyte e N-Large) os torna promissores no cultivo da uva 'Superior Seedless', fornecendo maior número de alternativas aos produtores da região do Vale do São Francisco.

Trials were carried out in Juazeiro, Bahia State, Brazil, aiming to test plant regulators composed by gibberellin, cytokine and auxin effects on chemical quality of Superior Seedless grape berries. The first trial studied the effects of Stimulate (bio regulator) and X-Cyte (cytokine) associated to a new gibberellin formulation (N-Large ) and associated to Pro-Gibb , which is a product used as source of gibberellin. Products were sprayed at berries development phase (18, 21, 51 and 56 days after spur-pruning). Treatments were: T1: Pro-Gibb ; T2: Stimulate (Dose 1); T3: Stimulate (Dose 2); T4: Stimulate (Dose 3); T5: Pro-Gibb + X-Cyte (Low Dose - DB); T6: Pro-Gibb + X-Cyte (Intermediate Dose - DM); T7: Pro-Gibb + X-Cyte (High Dose - DA); T8: N-Large ; T9: N-Large + X-Cyte (DB); T10: N-Large + X-Cyte (DM); T11: N-Large + X-Cyte (DA). The second trial aimed to assess the effect of the new gibberellin formulation (N-Large ) associated or not with cytokine (X-Cyte ) also sprayed straight over the bunches at berries development phase (17, 55 e 66 days after spur-pruning). Treatments were: T1: Pro-Gibb - blank; T2: N-Large (DB); T3: N-Large (DM); T4: N-Large (DA); T5: N-Large (DB) + X-Cyte (DB); T6: N-Large (DB) + X-Cyte (DM); T7: N-Large (DB) + X-Cyte (DA); T8: N-Large (DM) + X-Cyte (DB); T9: N-Large (DM) + X-Cyte (DM); T10: N-Large (DM) + X-Cyte (DA); T11: N-Large (DA) + X-Cyte (DB); T12: N-Large (DA) + X-Cyte (DM); T13: N-Large (DA) + X-Cyte (DA). Experimental design was random blocks with four repetitions with each repetition/parcel having three useful plants in the same row. At harvest, when bunches average had soluble solids over 15 ºBrix, berries were collected for soluble solids, pH, titratable acidity analysis as well as (SS/AT) ratio calculation. In both trials, plant regulators evaluated did not provide significant changes on chemical quality of 'Superior Seedless' grape berries. Therefore, the lack of differences on response between the commercially used product (Pro-Gibb) and the other

Interaction between cochleata and stipule-reduced mutations results in exstipulate hypertrophied leaves in Pisum sativum L.

In the wild type P. sativum, each of the adult plant stem nodes, bears a pair of sessile foliaceous stipules and a petiolated unipinnately compound leaf of 4 to 6 leaflets and 7-9 tendrils. The stipule-reduced (st) and cochleata (coch) single null mutants and coch st double null mutant differ fom the wild type in respectively having sessile stipules of much reduced size, petiolated simple and/or compound leaf-like stipules and no stipules. It is also known that coch leaves are somewhat bigger than st and wild type leaves. Here, pleiotropic phenotype of coch st double mutant was investigated. The morphologies of stipules and leaf were quantified in the field grown plants and microcultured shoots, latter in the presence and absence of gibberellic acid and N-1-naphthylphthalamic acid. The observations showed that as compared to the corresponding plants or shoots of COCH ST (WT) genotype, (a) coch st plants bore leaves in which all the organs were hypertrophied; (b) full complement of leaflets and 3-5 tendrils were formed on leaf; (c) the microcultured coch st shoots were taller despite lower number of nodes, and (d) they also produced leaves in which all the organs were bigger and the ratio of leaflets/tendrils was higher. It was concluded that in coch st double mutant (a) ST function is essential for stipule primordium differentiation, in the absence of COCH function and (b) absence of negative feedback loops between simple stipules and compound leaf for metabolite utilization allows hypertrophied growth in leaves.

Prestimulation of wheat seedlings with gibberellic acid followed by application of an agitated high dilution of the same hormone

In previous multicentre studies, the influence of a homeopathic ultra-high dilution of gibberellic acid on wheat growth was scrutinized. Data showed that this test dilution slowed down stalk growth when experiments were performed in the autumn season. The aim of this work was to test the hypothesis that pretreatment of grains with high concentrations of gibberellic acid would enhance the growth-inhibiting effect of the ultra-high dilution of the plant hormone. Grains of winter wheat (Triticum aestivum, 500 or 1000 per group) were pretreated with (non-agitated) gibberellic acid 10-5, 10-4 and 10-3 parts by weight (Ge-5, Ge-4, Ge-3) or with water (?W0?) for control prior to further treatment. Grains were then observed under the influence of extremely diluted gibberellic acid (10-30 parts by weigth) prepared by stepwise dilution and agitation according to a protocol derived from homeopathy (?G30x?). Analogously prepared water was used for control (?W30x?). Seedlings were allowed to develop under standardized conditions for 7 days; plants were harvested and stalk lengths were measured. Of the four pretreatment variants under study, Ge-3 yielded most growth, followed by Ge-4 , Ge-5 and finally W. This outcome was modulated by the application of G30x in that the inhibition obtained with G30x as compared to W30x was the greater the lower the pretreatment concentration of G had been. The hypothesis that pretreatment of grains with high concentrations of gibberellic acid would enhance the growth inhibiting effect of G30x had to be rejected. Rather, G30x slowed down stalk growth most in the W0 group with p < 0.001, only moderately in the Ge-5 and Ge-4 group and not at all in the Ge-3 group.