Effects of light regulation on the synthesis of secondary metabolites in medicinal plants / 药学实践与服务

Secondary metabolites of medicinal plants are extremely important to human health because of their special pharmacological activities or efficacy. They are the main source of drugs, health care products, and cosmetics. As human beings continue to pursue health and longevity, the demand in the pharmaceutical market continues to grow. It becomes especially important to improve the production and quality of secondary metabolites of medicinal plants. Plant secondary metabolites are a kind of adaptation of plants to their environment and are the result of the interaction between plants and biotic and abiotic factors during the long-term evolution process. The production and accumulation of secondary metabolites in medicinal plants are mainly affected by plant genetic factors and environmental factors. Among them, light environment is extremely important for their synthesis. Therefore, light regulation has long been a research focus for many scholars in China and abroad. In this article, we the recent research progress on the effects of light regulation on the secondary metabolites of medicinal plants were reviewed, mainly focusing on the effects of light quality, light intensity and photoperiod, in order to provide theoretical basis and practical guidance for the efficient production of secondary metabolites with important pharmacological activities.

In vitro photoautotrophic cultivation of Melocactus zehntneri: insights from allometric characteristics from germination to acclimatization

Melocactus zehntneri is a species of ornamental relevance suffering anthropogenic pressures, putting its preservation at risk. Thus, alternatives for propagating and conserving this species are needed. This study evaluated the effect of photoautotrophic cultivation of M. zehntneri to produce plants well acclimated to natural conditions. The seeds underwent different imbibition times before in vitro germination. Besides the growth room, a greenhouse hosted the photoautotrophic cultivation of seedlings. Vermiculite replaced agar in the culture medium. The imbibition pre-treatment in distilled water and the growth environments affected some parameters linked to germination. The greenhouse provided better characteristics for plants grown in vitro and for acclimatization than those kept in the growth room. Plants cultivated and acclimated ex vitro in a greenhouse photoautotrophic environment showed improved characteristics regarding ornamental significance.

Allelopathy of Ricinus communis and light spectrum variation decrease emergence and growth of Cyperus rotundus

Weeds negatively influence agricultural production. However, those losses depend on weed specie, its time of emergence, and period of interference on agricultural crops. Synthetic herbicides are commonly used to control these plants species; however, they may cause damage to the environment, human beings and animals health, and this problem justify the need to develop alternative bioherbicides. To evaluate the allelopathic potential of Ricinus communis (Castor bean) and light spectrum variation on the emergence and growth of Cyperus rotundus L., a trial was carried out in a protected environment with 15% of brightness reduction at the Center for Agricultural and Environmental Sciences at the Paraíba State University. Four aqueous extract concentrations of R. communis leaves were tested (0, 5, 10, and 15%) and four light spectrums variations (white, purple, blue, and red lights). Variables such as emergence, length, dry matter accumulation and growth rates of shoots and root of C. rotundus seedlings were assessed. Data were analyzed by normality test, analysis of variance, polynomial regression, and averages test. Soot and root emergence, length, and dry matter accumulation of C. rotundus seedlings were reduced due to the allelopathy caused by R. communis aqueous extract leaves (15% concentration) and under purple or red light spectrum radiation.

Effects of light quality on growth and icariin flavonoid content of Epimedium pseudowushanense under different light intensity / 中国中药杂志

In this study, the growth index including plant height, compound leaf area, specific leaf area, leaf water content, number of branches, and leaf biomass per plant and the icariin flavonoids such as epimedin A, epimedin B, epimedin C and icariin of Epimedium pseudowushanense were determined on 30 d and 60 d under light intensity(18.2±2.5) μmol·m~(-2)·s~(-1)(L1) and(90.9 ±2.5) μmol·m~(-2)·s~(-1)(L2), and white light as control, red light, blue light and yellow light were used as three light quality treatments, to study the effect of light quality on the growth and flavonoids accumulation of E. pseudowushanense. The E. pseudowushanense was sui-table for growth under L1 light intensity, the blue light treatment significantly reduced the leaf area, but had little effect on the stem height, the red light treatment and the yellow light treatment had no obvious effect on the stem height and leaf area, but the yellow light treatment significantly increased the germination of new branches, and had a sustained promoting effect, and the biomass was significantly higher than the white light treatment at 60 d. The content of icariin flavonoids in red light, blue light and yellow light treatment was higher than that in white light treatment at 30 d and 60 d under L1 light intensity, while yellow light treatment promoted the synthesis of icariin flavonoids to the largest extent, which was 1.8 and 1.9 times of white light treatment(30 d and 60 d).Under L2 light intensity, the effect of strong light on promoting stem germination became the main factor, while the yellow light treatment showed no significant effect on promoting stem germination, and the red light treatment exhibited a significant effect on reducing leaf area. Icariin flavonoids under red light, blue light and yellow light treatment were all lower than that under white light treatment, that is, the effect of white light treatment on the synthesis of icariin flavonoids is better than red light, blue light and yellow light treatment. When the time of strong light treatment was longer, the degradation range of icariin flavonoids in other light treatment appeared, while red light treatment promotes the synthesis of icariin flavonoids. Therefore, the influence of light quality on E. pseudowushanense is quite different under different light intensity, no matter from growth index or flavonoid content index. The results support that the biomass and icariin flavonoid content can be increased by providing appropriate red and yellow light.

Effects of red light and blue light on root morphology and accumulation of bioactive compounds in Salvia miltiorrhiza / 中草药

Objective: Investigate the effects of different intensity of white light, red light and blue light on root morphology and bioactive compounds accumulations of Salvia miltiorrhiza. Methods: The seedlings of S. miltiorrhiza were treated with 4 intensities of white light, red light and blue light, respectively, the morphologic index of root such as the lateral root number, lateral root diameter as well as the content of seven bioactive compounds were determined. Results: The influences of different light quality on the above-ground morphological indexes of S. miltiorrhiza were distinct. Red light of 100 μmol/(m2∙s) and 200 μmol/(m2∙s) promoted the occurrence of lateral root, and blue light of 200 μmol/(m2∙s) and 300 μmol/(m2∙s) significantly increased the root biomass. The accumulation of different bioactive compounds was distinctly affected by light quality and light intensity, the accumulation of tanshinones was more sensitive to the light treatments than that of phenolic acids. Conclusion: Light regulates the lateral root development and accumulations of bioactive compounds simultaneously, the application of artificial light is a promising method to improve the yield and quality of S. miltiorrhiza.

Effect of light quality on total gypenosides accumulation and related key enzyme gene expression in Gynostemma pentaphyllum / 中草药·英文版

Objective: Light quality has effect on the accumulation of gypenosides in the medicinal plant Gynostemma pentaphyllum in the family Cucurbitaceae, while the squalene synthase (SS) and squalene epoxidase (SE) are the key enzymes for gypenoside biosynthesis. The objective of this study was to elucidate the relationship between light quality and biosynthesis key enzyme involving the regulation of gypenoside accumulation. Methods: The content of total gypenosides was measured by colorimetric method and the expression of SS and SE gene was determined by quantitative Real-time PCR in the seedlings of G. pentaphyllum which were grown with different light quality. Results: Light quality showed remarkable impacts on the accumulation of total gypenosides. The highest content of total gypenosides in the plant under red light condition was determined, followed by blue light and white light, while the lowest content was recorded under dark condition. qRT-PCR analysis proved that the expression levels of SS and SE genes were also affected by light quality. The high-level gene expressions of SS and SE were found in the plant under red light condition, followed by blue light, with the least content in darkness. The statistical analysis revealed that the total gypenosides were significantly different in different light treatment and the content of total gypenosides was positively related to the expression of SS and SE genes. Conclusions: Light quality regulates gypenoside accumulation via altering the expression of SS and SE in G. pentaphyllum.

Effects of light quality and intensity on growth, related enzymes activity, and components of Polygala tenuifolia / 中草药

Objective To study the growth physiology and components of Polygala tenuifolia under different light quality and intensity, and provide theoretical basis for the artificial cultivation, yield improvement, and increasing the target composition of P. tenuifolia. Methods Using P. tenuifolia shoots as the experimental material, four kinds of ights (white, yellow, red, and blue) as light quality, the light intensity was set at 100, 300, and 500 μmol/(m2∙s) to determinate the plant height, root length, leaf length, leaf width, malondialdehyde (MDA) content, antioxidant enzyme activity, and secondary metabolite content in P. tenuifolia after 30 d of illumination. Results Under the red light, P. tenuifolia had the highest plant height, the longest root length and leaf length, and the largest biomass. Under the yellow light, the MDA content was the lowest, and the MDA content was the highest under white light. The activities of SOD, POD, and CAT were significantly increased under red and blue light. The highest content of total flavonoids, total phenols, and 3,6'-disinapoyl sucrose under blue light. Different light qualities had no significant effect on the content of polygalaxanthone III. The biomass of plant height and the 3,6’-disinapoyl sucrose content were the highest under the light intensity of 300 μmol/(m2∙s). P. tenuifolia had the longest roots under the light intensity of 500 μmol/(m2∙s), and the content of MDA and the activities of POD, SOD, and CAT increased with the increase of light intensity. Conclusion Red light has the strongest promoting effect on the roots of P. tenuifolia. Red and blue light significantly increases the activity of POD, SOD, and CAT. Blue light promotes the accumulation of total flavonoids, total phenols, and 3,6’-disinapoyl sucrose. The light intensity of 500 μmol/(m2∙s) has the strongest promoting effect on the roots of P. tenuifolia, and the activities of POD, SOD, and CAT in leaves were higher. Different light qualities had no significant effect on the contents of total flavonoids, total phenols, and polygalaxanthone III. The light intensity of 300 μmol/(m2∙s) promotes the accumulation of 3,6’-disinapoyl sucrose.

Fruit sphere microenvironments and berry phenolic content of Cabernet Sauvignon (Vitis vinifera L.) cultivated under rain-shelter systems with coloured plastic film

Abstract Rain-shelter cultivation has been proven an important cultivation method for grape-plantings in continental monsoon climate zones, of which white plastic films are the most common shelter material. However, while this method and material reduces the occurrence of the disease, it can also decrease the grape berry quality. Five colours (including red, yellow, blue, purple, and white) of plastic films were covered above Cabernet Sauvignon (Vitis vinifera L.) grapevine rows before veraison. Rain-shelter cultivation reduced air temperature, wind speed, and total solar radiation and enhanced relative humidity in the fruit sphere of grapevines. For each particular colour plastic film, the irradiance of its corresponding spectrum band in the canopy of vines was higher than with other colour plastic films. Meanwhile, the blue plastic film treatment significantly promoted the accumulation of total phenolics, anthocyanins, flavonoids, tannins, and phenolic acids more than the other colours of plastic films. Blue plastic films are more beneficial for berry quality promotion of wine grapes, especially Cabernet Sauvignon, under rain-shelter cultivation in continental monsoon climate zones.

Impact of light quality on flavonoid production and growth of Hyptis marrubioides seedlings cultivated in vitro

ABSTRACT Hyptis marrubioides Epling, Lamiaceae, a species from Brazilian Cerrado, has been used against gastrointestinal infections, skin infections, pain, and cramps. Herein, H. marrubioides seedlings were cultured in vitro under different wavelengths (white, blue, green, red, and yellow) with 50 µmol m-2 s-1 irradiance and a 16-h photoperiod. After 20 and 30 days of cultivation, shoot length, leaf number, fresh mass, and dry mass were evaluated. The flavonoid rutin content was determined by the HPLC-DAD method. The shoots were longer in plants cultivated under yellow (16.603 ± 0.790 cm, 1.8-fold), red (15.465 ± 0.461 cm, 1.7-fold), and green (14.677 ± 0.737 cm, 1.6-fold) lights than in control plants exposed to white light (9.203 ± 0.388 cm). The number of leaves increased in plants exposed to red (23.425 ± 1.138, 1.1-fold) and green (22.725 ± 1.814, 1.1-fold) lights, compared to control plants (20.133 ± 0.827). Fresh (0.665 ± 0.048 g, 1.2-fold) and dry (0.066 ± 0.005 g, 1.3-fold) mass of seedlings were the highest in seedlings grown under red light, compared to seedlings grown under white light (0.553 ± 0.048 and 0.028 ± 0.004, respectively). However, rutin production was higher under white (0.308 mg g-1 of dry weight) and blue lights (0.298 mg g-1 of dry weight). Thus, red light induces plant growth and increases leaf number and dry weight in in vitro-cultivated H. marrubioides, whereas blue and white lights promote the greatest rutin accumulation.

Growth, photosynthetic pigments and production of essential oil of long-pepper under different light conditions

ABSTRACT Piper hispidinervum C. DC. is popularly known as long-pepper and it owns a commercial value due to the essential oil it produces. Long-pepper oil is rich in safrole and eugenoln components that have insecticidal, fungicidal and bactericidal activity. It has been establish that to medicinal plants light influences not only growth but also essential oil production. The growth, the content of photosynthetic pigments and the essential oil production of Piper hispidinervum at greenhouses with different light conditions was evaluated. The treatments were characterized by cultivation of plants for 180 days under different light conditions, produced by shading greenhouses with 50% and 30% of natural incident irradiance, two colored shading nets red (RN) and blue (BN) both blocking 50% of the incident radiation and one treatment at full-sun (0% of shade). The results showed that the treatments of 50% shade and RN and BN were the ones which stimulated the greater growth. Blue and red light also had the best production of photosynthetic pigments. Essential oil yielded more under full sun therefore this is the most indicated condition to produce seedlings for the chemical and pharmaceutical industry.

Effects of light quality on growth and internal quality of Whitmania pigra / 中国中药杂志

In this study, four light color treatments (red blue, white, natural light) were tested to determine effects of light spectrum on the growth of larval Whitmania pigra (30 days old) at the same intensity. The experiment lasted for 50 days. The specific growth rate (SGR) under blue light condition was significantly higher during 30 days to 40 days. At the end of the experiment, specific growth rate (SGR) and weight gain rate under red light condition were higher (P<0.05) than those under other groups. Meanwhile, the enzymes activities of digestive enzymes (protease, amylase and lipase) were higher under red light condition. However, the enzymes activities of antioxidant enzymes (SOD, CAT, ALP) were lower under white light condition compared with the other treatments（P＜0.05）. In addition, no significant changes were observed for water content, total ash, acid insoluble ash, pH and antithrombin activity in the all treatments. After 50 days, the digestive enzymes and growth rate were higher under red light condition but antioxidant enzymes were lower under white light condition. Furthermore, light spectrum has no significant effect on the internal quality of Wh. pigra.

Progress of effects of light on plant flavonoids / 中国中药杂志

As an important secondary metabolites of medicinal plant, flavonoids plays a very important role on itself including light protection and antioxidant. Light is one of the important environmental factors which impacts the secondary metabolites of plant and has a significant impact on biological synthesis of flavonoids. This paper reviews the recent progress of the effects of light on flavonoids on the plants focusing from light intensity and light quality, and summarizes briefly functions of the phenylalanine ammonia lyase (PAL) in plant secondary metabolism and the upstream key enzyme chalcone synthase (CHS) in flavonoid biosynthetic pathway.

Effects of light quality on cell growth and psbA promoter of engineered Synechococcus sp. PCC7002 / 生物工程学报

Light quality can regulate both psbA genes and vector promoter psbA of the engineered Synechococcus. Through light regulation, we tried to improve yield of the recombinant protein for vp28 gene-expressed Synechococcus sp. PCC7002. To drive photon-capturing efficiently, three limiting factors (irradiance, temperature and pH) were optimized by measuring net photosynthesis. High cell density cultures were performed with variant ratios of white, red and blue light in a 5-L photo-bioreactor. Yields of biomass, expressions of vp28 and transcription levels of psbA were compared. High ratio blue light-induced vp28 transcription had tripled and the relative accumulation of VP28 protein was doubled. The relative expressions of psbAII and psbAIII had positive correlations with higher ratio of blue light, not the red light. With high ratio red light inducing, dry biomass reached 1.5 g/L in three days. Therefore, we speculated that red light accelerated biomass accumulation of the transgenic strain and blue light promoted transcription for PpsbA and psbA. These results provided useful information for mass production of cyanobacteria and its secondary metabolites.

Effect of light quality on growth and triterpenic acid content of Ganoderma lucidum mycelium / 中草药

Objective: To study the effect of light quality on the growth as well as triterpenic acid content and component of Ganoderma lucidum mycelium. Methods: Light-emitting diode (LED) was used as sources of light, the growth index, content and component of triterpenic acids in G. lucidum mycelium cultured under different LED conditions were investigated along with culture time. Results: The growth rate, morphology, biomass, total contents and components of triterpenic acid in G. lucidum mycelium varied under different lights. The mycelium cultured under blue light maintained stable growth during the whole period; Under red light, both growth rate and biomass of mycelium were the highest in early time, subsequently, decreased sharply and grew slowly. Under green light, both growth rate and biomass of mycelium were the lowest in early and medium phases, while increased significantly later, especially dry matter. Triterpenic acids were highly produced on the day 7 of cultivation, while decreased in content and increased in types. Green light and blue light had a distinct advantage of improving the type and content triterpenic acids in G. lucidum. Conclusion: Light quality affects the growth as well as the content and component of triterpenic acids in G. lucidum mycelium, and blue light irradiation is the best for the steady growth and triterpenic acids accumulation.

Dimorphic cypsela germination and plant growth in Synedrella nodiflora (L.) Gaertn. (Asteraceae) / Germinação de cipselas dimórficas e crescimento de plantas de Synedrella nodiflora (L.) Gaertn. (Asteraceae)

Synedrella nodiflora is a weed species that has dimorphic cypselas: winged peripheral and lanceolate shaped central. The aim of this work is to describe the reproductive capability by measuring dimorphic cypselas morphology, imbibition rates and germinative patterns under temperature, light quality and water availability gradients, and compare the plant growth between two light treatments. The central cypselas were lighter, longer and its pappi were more elongated than the peripheral ones, favoring its dispersion. Neither type had deep dormancy and both of them germinated with the same pattern under the optimum conditions. Both cypselas showed higher germinability in temperatures between 25 and 30 °C, under white light and high water availability, although there are some differences between the types, mainly at dark treatments. Plants grown in direct sunlight accumulated more biomass, allowing for higher plant development and inflorescence production, although shaded light plants capitulum had a higher central: peripheral ratio than the direct sunlight treatment. S. nodiflora cypselas germinate better in unfiltered light places, although the plants are adapted to shady conditions. The species showed high germination potential over a wide range of environmental conditions, as well as fast plant development. All of these features favor distribution in environmental sites.

Synedrella nodiflora é uma planta daninha que possui cipselas dimórficas: periférica alada e central com forma lanceolada. O objetivo deste trabalho foi caracterizar a capacidade reprodutiva por medição da morfologia das cipselas, taxas de embebição e padrões germinativos sob gradientes de temperatura, qualidade de luz e disponibilidade de água, e comparação do crescimento das plantas sob dois tratamentos luminosos. As cipselas centrais foram mais leves, compridas e seus pappi foram mais alongados que as periféricas, o que favorece sua dispersão. Nenhum dos tipos exibiu dormência profunda, germinando sob o mesmo padrão nas condições ótimas. Ambas as cipselas apresentaram maior germinabilidade sob temperaturas entre 25 e 30 °C, sob luz branca e alta disponibilidade hídrica, apesar de haver algumas diferenças entre os tipos, principalmente em tratamentos de escuro. Plantas que cresceram em luz solar direta acumularam maior quantidade de biomassa, permitindo o maior desenvolvimento vegetal e produção de inflorescências, contudo capítulos das plantas sombreadas tiveram uma razão central:periférica maior que tratamentos com luz direta. Cipselas de S. nodiflora germinam melhor em locais com luz não filtrada, contudo as plantas são adaptadas à condição de sombra. A espécie apresentou um alto potencial germinativo sob uma ampla gama de condições ambientais, assim como rápido desenvolvimento, todas essas características favorecem a distribuição ao longo dos ambientes.

Diodos emissores de luz e concentrações de BAP na multiplicação in vitro de morangueiro / Light-emitting diodes and BAP concentrations in the in vitro strawberry multiplication

Realizou-se um estudo para avaliar o efeito de fontes de luz na micropropagação de morangueiro, com níveis crescentes de BAP no meio de cultivo. Para tanto, inocularam-se gemas de brotações da cultivar 'Sabrosa' em meio MS com 30g L-1 de sacarose, 100mg L-1 de mio-inositol, 7g L-1 de ágar e BAP (0; 0,3; 0,6; 0,9; e 1,5mg L-1), em pH 5,8. Os explantes foram cultivados a 25+2°C, com 16 horas de fotoperíodo e luminosidade de 20µmol m-2 s-1, esta última fornecida por diferentes fontes de luz (LED azul-EDEB 3LA1, LED verde-EDET 3LA1, LED vermelho-EDER 3LA3, lâmpada fluorescente Growlux e lâmpada fluorescente branca). Os tratamentos foram dispostos em delineamento inteiramente ao acaso em um fatorial 5x5 (concentrações de BAP x fontes de luz), com seis repetições. O experimento foi repetido em três subcultivos sucessivos de 35 dias cada. Nestes avaliaram-se o número de brotações por explante e a altura das brotações. Ao final do terceiro subcultivo, determinaram-se, ainda, as concentrações de carotenoides e de clorofilas a e b, independentemente do nível de BAP. Maior número de brotações por explante foi obtido sob LEDs vermelhos e verdes. Concentrações de BAP no meio de cultura entre 0,82 e 1,22mg L-1, dependendo da fonte de luz, proporcionaram maior multiplicação in vitro de brotações. Sob todas as fontes de luz foram obtidas brotações de maior comprimento em meio isento de BAP. Brotações cultivadas sob LEDs vermelhos apresentaram maior quantidade de pigmentos fotossintéticos, enquanto aquelas sob LEDs verdes e lâmpadas Growlux apresentaram a menor.

The objective of this research was to evaluate the effect of different sources of light in strawberry micropropagation, under increasing levels of BAP in culture medium. 'Sabrosa' shoots were inoculated in MS medium supplemented with 30g L-1 sucrose, 100mg L-1 myo-inositol, 7 agar g L-1 and BAP (0; 0.3; 0.6; 0.9; e 1.5mg L-1), pH 5.8. The explants were cultivated at 25+2°C, 16 hours photoperiod and 20µmol m-2 s-1. The luminosity was supplied by different sources of light (blue-EDEB 3LA1 LED, green-EDET 3LA1 LED, red-EDER 3LA3 LED, Growlux fluorescent lamp and white fluorescent lamp). The experimental design was a factorial entirely randomized (5 concentrations of BAP x 5 light sources) with six replications. The experiment was repeated in three successive subcultures of 35 days each, being evaluated the shoot number per explant and shoot height. The carotenoids and chlorophyll a and b determinations were carried out after the third subculture, independently of BAP concentration. Shoot number per explant was higher under red and green LEDs. BAP concentrations between 0.82 and 1.22mg L-1 in culture medium showed higher multiplication rate depending on the light source. Shoot length was highest in culture medium without BAP under all light sources. Shoots cultivated under red LEDs showed higher concentration of photosynthetic pigments, while those under green LEDs and Growlux light bulbs showed the lowest.

Germination in seed species ingested by opossums: implications for seed dispersal and forest conservation

Seed germination in plant species consumed by opossums, genus Didelphis, was investigated in southern Brazil, in order to improve knowledge of the strategies of zoochorous plants in the Neotropics. Seeds were obtained from opossum feces. Thirteen of the most frequent species in the diet of local opossums were tested for germination rates and germination responses under different qualities (red/far red ratio) and different intensities of light. Most seeds from feces germinated similarly to the control groups, except for seeds of Rubus rosifolius, which appeared to depend on gut passage. Other experiments revealed that most seeds in the opossums' diet were of pioneer species, with most germination occurring during favorable humid conditions in the rainy season. A few species showed negative photoblastism, or no dormancy pattern. Small mammals are suggested as possible tools for area recuperation programs, through seed dispersal of many pioneer and some shade-tolerant plants, under suitable management.

Com o objetivo de fornecer conhecimento adicional acerca das estratégias de germinação adotadas por espécies de plantas zoocóricas da Região Neotropical, foram examinadas a dormência e germinação de sementes consumidas por marsupiais do gênero Didelphis. As sementes foram obtidas de fezes dos animais capturados em armadilhas, sendo então analisadas. As espécies mais freqüentes na dieta dos gambás (N = 13) foram testadas quanto a sua viabilidade e possíveis mecanismos de quebra de dormência pela luz (condições de luz vs. sombra vs. escuro; e sob red/far red ratio). A maioria das espécies provenientes das fezes germinou similarmente ao grupo controle, exceto por Rubus rosifolius que parece depender da passagem pelo trato digestivo para a germinação. Outros experimentos mostraram que as espécies de plantas eram principalmente pioneiras, com quebra de dormência principalmente durante a estação mais úmida e favorável ao desenvolvimento. Uma menor proporção de espécies apresentou fotoblastismo negativo ou nenhum padrão de dormência. Os resultados mostram que estes pequenos mamíferos podem ser utilizados em programas de recuperação de áreas degradadas, com enfoque na dispersão de sementes de plantas pioneiras

Effect of light intensity and light quality on growth and total flavonoid accumulation of Erigeron breviscapus / 中草药

Objective To study the effect of light intensity and light quality on the growth and total flavonoid accumulation of Erigeron breviscapus. Methods Young plants of E. breviscapus were planted under various color films and light intensities, their biomass and total flavonoid content were determined when plants flowered. Results The biomass and total flavonoid content of individuals under 100% and 80% sunshine were higher than those under 50% sunshine. The biomasses of plants under yellow, red, purple, or blue film were lower than those under white film. Under the blue film, the total flavonoid content of the plant was the highest; while under white film, the total flavonoid yield was the highest. Conclusion Light intensity and light quality significantly affect the growth and total flavonoid accummulation of E. breviscapus. The biomass and total flavonoid yield are the highest when under full sunshine.