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1.
Food Chem ; 343: 128445, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33129614

RESUMO

Pueraria is a medicine plant with rich starch, and thus can be a potential agricultural and industrial resource. In this study, we evaluated the root tuber yield of a cultivar of starch kudzu (Pueraria thomsonii) and the starch accumulation during expansion period of root tuber. Additionally, mineral elements were quantified in root tuber and starch. The results indicated that the starch kudzu cultivar owned high yield of root tuber (greater than42 tons/hm2), high starch content (greater than17% FW) in root tuber, and rich accumulation of beneficial mineral elements. Interestingly, the root tuber of P. thomsonii contained a high concentration of selenium (70 mg/kg FW) and strontium (40 mg/kg FW), and thus it can be utilized as a Se and Sr rich food. Furthermore, Se and Sr can be well preserved in starch through the optimized starch extraction method.


Assuntos
Minerais/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Pueraria/crescimento & desenvolvimento , Pueraria/metabolismo , Amido/metabolismo , Raízes de Plantas/metabolismo
2.
PLoS One ; 15(3): e0229835, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32176706

RESUMO

Quantifying the economic impacts of invasive species is an essential step in developing and prioritizing invasive species management. In particular, kudzu, Pueraria montana (Lour.) Merr. is an aggressive and non-native vine that not only causes ecological damage and reduces biodiversity, but can have multiple economic consequences such as loss of timber value and volume. Using current infestation locations in Oklahoma, southcentral USA, a Monte Carlo simulation was run to estimate the natural as well as anthropogenic spread rate of kudzu in the next five years. Simulations were supplemented with an economic impact analysis within the Impact Analysis for PLANing (IMPLAN) platform. To account for economic loss in the forest product industry, a replacement cost approach with a sensitivity analysis was conducted. Occurrence data collections revealed that current kudzu populations are already established in Oklahoma forests. The results demonstrate that by year five, total industry output could be reduced by $167.9 million, which will influence 780 jobs in the most extreme case scenario. The predicted economic loss due to kudzu expansion could act as an incentive for appropriate management practices and plans to be implemented.


Assuntos
Espécies Introduzidas/economia , Pueraria/crescimento & desenvolvimento , Agricultura Florestal/métodos , Oklahoma
3.
Appl Biochem Biotechnol ; 190(1): 57-72, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31301012

RESUMO

To address the high demand for Pueraria candollei var. mirifica (PM) used as the active ingredient in health products and its difficulty to cultivate in the field, the growth and production of deoxymiroestrol (DME) and isoflavonoid (ISF) phytoestrogens in PM cell suspensions were studied. In a 125-mL shake flask, the cell suspension produced DME [78.7 ± 8.79-116 ± 18.2 µg/g dry weight (DW)] and ISF (140 ± 6.83-548 ± 18.5 µg/g DW), which are the predominant ISF glycosides. While ISF aglycones accumulated in the PM cell suspension cultured in the airlift bioreactor. The DME content was increased to 976 ± 79.6 µg/g DW when the PM cell suspension was cultured in the 5-L scale bioreactor. The production of DME and ISF was enhanced by elicitors including methyl jasmonate (MJ), yeast extract (YE), and chitosan (CHI). MJ produced the highest induction of DME accumulation, while ISF accumulation was the highest with YE treatment. Analysis of catalase activity implied that the elicitors enhanced ROS production, which resulted in the enhancement of DME and ISF production and accumulation in PM cell suspension cultures. PM cell suspension culture is a promising source of beneficial PM phytoestrogens that exhibit bioactivity that may useful for the treatment of menopausal symptoms.


Assuntos
Reatores Biológicos , Flavonoides/biossíntese , Pueraria/metabolismo , Catalase/metabolismo , Cumarínicos/farmacologia , Flavonoides/farmacologia , Fitoestrógenos/metabolismo , Pueraria/citologia , Pueraria/crescimento & desenvolvimento , Esteroides/biossíntese , Esteroides/farmacologia
4.
Plant Cell Environ ; 42(11): 3121-3139, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31124152

RESUMO

The ability to transport water through tall stems hydraulically limits stomatal conductance (gs ), thereby constraining photosynthesis and growth. However, some plants are able to minimize this height-related decrease in gs , regardless of path length. We hypothesized that kudzu (Pueraria lobata) prevents strong declines in gs with height through appreciable structural and hydraulic compensative alterations. We observed only a 12% decline in maximum gs along 15-m-long stems and were able to model this empirical trend. Increasing resistance with transport distance was not compensated by increasing sapwood-to-leaf-area ratio. Compensating for increasing leaf area by adjusting the driving force would require water potential reaching -1.9 MPa, far below the wilting point (-1.2 MPa). The negative effect of stem length was compensated for by decreasing petiole hydraulic resistance and by increasing stem sapwood area and water storage, with capacitive discharge representing 8-12% of the water flux. In addition, large lateral (petiole, leaves) relative to axial hydraulic resistance helped improve water flow distribution to top leaves. These results indicate that gs of distal leaves can be similar to that of basal leaves, provided that resistance is highest in petioles, and sufficient amounts of water storage can be used to subsidize the transpiration stream.


Assuntos
Folhas de Planta/crescimento & desenvolvimento , Caules de Planta/crescimento & desenvolvimento , Estômatos de Plantas/crescimento & desenvolvimento , Transpiração Vegetal/fisiologia , Pueraria/crescimento & desenvolvimento , Água/fisiologia , Transporte Biológico , Dióxido de Carbono/metabolismo , Gravitação , Fotossíntese/fisiologia , Folhas de Planta/metabolismo , Caules de Planta/anatomia & histologia , Estômatos de Plantas/anatomia & histologia , Estômatos de Plantas/fisiologia , Pueraria/anatomia & histologia , Pueraria/fisiologia , Água/metabolismo
5.
BMC Genomics ; 19(1): 439, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29871589

RESUMO

BACKGROUND: Kudzu, Pueraria montana var. lobata, is a woody vine native to Southeast Asia that has been introduced globally for cattle forage and erosion control. The vine is highly invasive in its introduced areas, including the southeastern US. Modern molecular marker resources are limited for the species, despite its importance. Transcriptomes for P. montana var. lobata and a second phaseoloid legume taxon previously ascribed to genus Pueraria, Neustanthus phaseoloides, were generated and mined for microsatellites and single nucleotide polymorphisms. RESULTS: Roche 454 sequencing of P. montana var. lobata and N. phaseoloides transcriptomes produced read numbers ranging from ~ 280,000 to ~ 420,000. Trinity assemblies produced an average of 17,491 contigs with mean lengths ranging from 639 bp to 994 bp. Transcriptome completeness, according to BUSCO, ranged between 64 and 77%. After vetting for primer design, there were 1646 expressed simple sequence repeats (eSSRs) identified in P. montana var. lobata and 1459 in N. phaseoloides. From these eSSRs, 17 identical primer pairs, representing inter-generic phaseoloid eSSRs, were created. Additionally, 13 primer pairs specific to P. montana var. lobata were also created. From these 30 primer pairs, a final set of seven primer pairs were used on 68 individuals of P. montana var. lobata for characterization across the US, China, and Japan. The populations exhibited from 20 to 43 alleles across the seven loci. We also conducted pairwise tests for high-confidence SNP discovery from the kudzu transcriptomes we sequenced and two previously sequenced P. montana var. lobata transcriptomes. Pairwise comparisons between P. montana var. lobata ranged from 358 to 24,475 SNPs, while comparisons between P. montana var. lobata and N. phaseoloides ranged from 5185 to 30,143 SNPs. CONCLUSIONS: The discovered molecular markers for kudzu provide a starting point for comparative genetic studies within phaseoloid legumes. This study both adds to the current genetic resources and presents the first available genomic resources for the invasive kudzu vine. Additionally, this study is the first to provide molecular evidence to support the hypothesis of Japan as a source of US kudzu and begins to narrow the origin of US kudzu to the central Japanese island of Honshu.


Assuntos
Perfilação da Expressão Gênica , Espécies Introduzidas , Repetições de Microssatélites/genética , Pueraria/crescimento & desenvolvimento , Pueraria/genética , Anotação de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Controle de Qualidade , Análise de Sequência
6.
Environ Entomol ; 46(3): 487-493, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28369558

RESUMO

We conducted a field study to determine seasonal egg parasitism rates of the kudzu bug Megacopta cribraria (F.) on the kudzu plant, Pueraria montana (Lour.) Merr. var. lobata (Willd.) Maesen et Almeida ex Sanjappa and Pradeep, in Tokyo, Japan, during the period from May 2014 to September 2014. The eggs of M. cribraria per 1 m2 of kudzu at four locations in Tokyo were collected weekly and parasitism rates were assessed. Eggs of M. cribraria were laid on the kudzu plant from May to September. Megacopta cribraria eggs were parasitized by two parasitoid species, Paratelenomus saccharalis (Dodd) and Ooencyrtus nezarae Ishii. Paratelenomus saccharalis first appeared in May, and its parasitism rates peaked in July and September. Ooencyrtus nezarae first appeared in June and its parasitism rates peaked in July. Except for one location which could not be statistically analyzed because of the small sample size, occurrence of parasitism by P. saccharalis and O. nezarae in M. cribraria egg masses was independent at one location and positively associated at two locations, suggesting that the use of host egg masses by P. saccharalis and O. nezarae is not mutually exclusive. Parasitism rates by P. saccharalis and O. nezarae were significantly lower for egg masses parasitized by both species than for those parasitized by a single species. The proportion of males among O. nezarae progeny was significantly higher for egg masses parasitized by O. nezarae together with P. saccharalis than for those parasitized by O. nezarae alone. These results suggest that parasitism of host egg masses by the two species is influenced by their interspecific interactions.


Assuntos
Heterópteros/parasitologia , Interações Hospedeiro-Parasita , Vespas/fisiologia , Animais , Feminino , Heterópteros/crescimento & desenvolvimento , Japão , Masculino , Óvulo/parasitologia , Pueraria/crescimento & desenvolvimento , Estações do Ano
7.
J Econ Entomol ; 110(1): 157-167, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28039424

RESUMO

Megacopta cribraria (F.), an invasive species introduced from Asia in 2009, is now prolific in the southeastern United States. Megacopta cribraria develops primarily on kudzu and soybean completing two generations. It is not well understood how this economic pest is affected by changes in geographic distribution in the United States or how population levels have changed since its establishment. The effect of insecticide application timing on field populations of M. cribraria is not well documented. These studies seek to understand how population dynamics of M. cribraria vary with geographic regions in Georgia. Effect of application timing on populations throughout the growing season was also examined. Weekly from 2012 to 2013, all life stages were enumerated from kudzu and soybean environments at several locations throughout Georgia from sweeps samples and flight intercept captures. Coordinates were recorded for locations, and classified as belonging to the Piedmont or Coastal Plain region of the state. Single spray trials were conducted from 2011-2014, and applications were made to soybean at intervals throughout the season. From 2012 to 2015, two kudzu patches near Griffin, GA, were monitored to detect population changes. Differences in population dynamics from locations around the state were found, but no clear effect of latitude, longitude, or region was observed. Insecticide applications applied in July suppressed nymph populations significantly better than treatments made earlier or later. Megacopta cribraria populations declined in 2014 and 2015 compared with 2012 and 2013. These studies provide the critical information for M. cribraria management in soybean in the southeastern United States.


Assuntos
Glycine max , Heterópteros , Controle de Insetos , Inseticidas , Distribuição Animal , Animais , Georgia , Herbivoria/efeitos dos fármacos , Heterópteros/crescimento & desenvolvimento , Heterópteros/fisiologia , Ninfa/crescimento & desenvolvimento , Ninfa/fisiologia , Óvulo , Dinâmica Populacional , Pueraria/crescimento & desenvolvimento , Estações do Ano , Glycine max/crescimento & desenvolvimento
8.
Arq. bras. med. vet. zootec ; 67(3): 809-818, May-Jun/2015. tab, graf
Artigo em Português | LILACS | ID: lil-753926

RESUMO

O objetivo deste trabalho foi estudar a produção e o valor nutritivo de nove espécies de leguminosas forrageiras herbáceas tropicais, cultivadas sob dois níveis de irradiação luminosa e seis frequências de corte na estação chuvosa, em Anhembi (SP), Brasil. Parcelas puras foram estabelecidas ao sol e sob plantação de Eucalyptus grandis, com 8 anos de idade, com 1.000 árvores/ha, que interceptou mais de 80% da radiação luminosa incidente. Avaliou-se a taxa de acúmulo de matéria seca, a proteína bruta e a digestibilidade in vitro da matéria seca em amostras de plantas colhidas em intervalos de 30, 60, 90 e 180 dias, com cortes adicionais aos 120 e 150 dias. Sob pleno sol, as leguminosas testadas toleraram cortes mais frequentes (intervalos de 30 - 90 dias), exceto o Lablab. Na sombra, o grau de tolerância variou conforme a espécie; em termos de produção de MS e de persistência, a Centrosema e a Puerária se destacaram dentre as demais leguminosas comparadas, quando os cortes foram realizados em intervalos de 60 dias, enquanto o Arachis e o Estilosantes foram os mais produtivos quando os cortes ocorreram em intervalos de 120 dias, mantendo o valor nutricional. O Alysicarpus e a Aeschynomene não persistiram sob o nível de sombreamento que prevaleceu nesse experimento.


The aim of this study was to evaluate the production and nutritive value of nine tropical legumes under two light intensities and six cutting regimens in the wet season, in Anhembi (SP) - Brazil. Pure stands were established in full light and under an eight-year-old eucalyptus plantation with 1.000 plants per hectare. The trees intercepted over80% of the incident radiation. Dry matter herbage accumulation, dry matter in vitro digestibility and crude protein under the cutting intervals 30, 60, 90 and 180 days, with additional cuttings at 120 and 150 days were evaluated. With the exception of Lablab, all other tested legume species tolerated higher cutting frequency under when grown under full sun light then under shade. The degree of shade-tolerance varied according to the species; Centrosema and Pueraria produced well at cutting intervals of 60 days, showing higher dry matter production and persistence while Arachis and Stylosanthes showed better results under longer cutting intervals, keeping the nutritional value, and can be indicated for differential grazing. Alysicarpus and Aeschynomene did not persist under the prevailing conditions.


Assuntos
Eficiência , Pastagens/análise , Pastagens/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Clitoria/crescimento & desenvolvimento , Pueraria/crescimento & desenvolvimento
9.
An Acad Bras Cienc ; 87(1): 519-28, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25714076

RESUMO

Plants have the ability to undergo morphophysiological changes based on availability of light. The present study evaluated biomass accumulation, leaf morphoanatomy and physiology of Neonotonia wightii and Pueraria phaseoloides grown in full sunlight, as well as in 30% and 50% shade. Two assays were performed, one for each species, using a randomized block design with 10 replicates. A higher accumulation of fresh mass in the shoot of the plants was observed for both species under cultivation in 50% shade, while no differences were detected between the full sunlight and 30% shade. N. wightii and P. phaseoloides showed increase in area and reduction in thickness leaf when cultivated in 50% shade. There were no changes in photosynthetic rate, stomatal conductance, water use efficiency and evapotranspiration of P. phaseoloides plants because growth environment. However, the shade treatments caused alterations in physiological parameters of N. wightii. In both species, structural changes in the mesophyll occurred depending on the availability of light; however, the amount of leaf blade tissue remained unaltered. Despite the influence of light intensity variation on the morphophysiological plasticity of N. wightii and P. phaseoloides, no effects on biomass accumulation were observed in response to light.


Assuntos
Pueraria/crescimento & desenvolvimento , Luz Solar , Adaptação Fisiológica , Biomassa , Fabaceae/classificação , Fabaceae/crescimento & desenvolvimento , Fabaceae/fisiologia , Fenótipo , Fotossíntese/fisiologia , Pueraria/fisiologia
10.
Zhongguo Zhong Yao Za Zhi ; 40(22): 4364-9, 2015 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-27097408

RESUMO

Puerariae Lobatae Radix, also known as Gegen, is a root derived from Pueraria lobata. Based on field investigation and the developmental anatomy of root tuber, we have elucidated the relationship between the growth of root tuber and the anomalous structure. The results of analysis showed that the root system of P. lobata was developed from seed and adventitious root and there existed root tuber, adventitious root and conductive root according to morphology and function. The root tuber was developed from adventitious root, its secondary structure conformed to the secondary structure of dicotyledon's root. With the development of root, the secondary phloem of root tuber appeared abnormal vascular tissue, which was distributed like ring in the outside of secondary vascular tissue. The root tuber might have 4-6 concentric circular permutation abnormal vascular tissuelobate, and was formed by the internal development of abnormal vascular tissue. The xylem and phloem of abnormal vascular tissue were the main body of the root tuber. The results reveal the abnormal anatomical structure development of P. lobata, also provides the theoretical basis for reasonable harvest medicinal parts and promoting sustainable utilization of resources of P. lobata.


Assuntos
Tubérculos/anatomia & histologia , Pueraria/crescimento & desenvolvimento , Raízes de Plantas/anatomia & histologia , Raízes de Plantas/crescimento & desenvolvimento , Tubérculos/crescimento & desenvolvimento , Pueraria/anatomia & histologia
11.
Biosci Biotechnol Biochem ; 78(6): 917-26, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25036114

RESUMO

We investigated the major leaf isoflavonoid contents of Pueraria mirifica from three different cultivars (PM-III, PM-IV, and PM-V) using reverse RP-HPLC analysis. The proportions and net levels of puerarin, daidzin, genistin, and daidzein in P. mirifica leaves were found to depend on the plant cultivar and to correlate with cultivation temperature and rainfall amount. The crude leaf-extracts were tested using the Yeast Estrogen Screen (YES) assay with both human estrogen receptors (hERα and hERß). Their estrogenic activity was higher when determined by the YES system containing hERß than that with hERα and was also higher when the Δsnq2 than the wildtype yeast was employed. The results open the possibility of selecting and cultivating certain P. mirifica cultivars at a farm scale to produce a sufficient supply of leaf material to act as a starting source for the commercial scale extraction of these major isoflavonoids.


Assuntos
Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Folhas de Planta/química , Pueraria/química , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Flavonoides/química , Humanos , Pueraria/crescimento & desenvolvimento
13.
New Phytol ; 203(1): 110-24, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24720813

RESUMO

Soil carbon (C) sequestration, as an ecosystem property, may be strongly influenced by invasive plants capable of depositing disproportionately high quantities of chemically distinct litter that disrupt ecosystem processes. However, a mechanistic understanding of the processes that regulate soil C storage in invaded ecosystems remains surprisingly elusive. Here, we studied the impact of the invasion of two noxious nonnative species, Polygonum cuspidatum, which produces recalcitrant litter, and Pueraria lobata, which produces labile litter, on the quantity, molecular composition, and stability of C in the soils they invade. Compared with an adjacent noninvaded old-field, P. cuspidatum-invaded soils exhibited a 26% increase in C, partially through selective preservation of plant polymers. Despite receiving a 22% higher litter input, P. lobata-invaded Pinus stands exhibited a 28% decrease in soil C and a twofold decrease in plant biomarkers, indicating microbial priming of native soil C. The stability of C exhibited an opposite trend: the proportion of C that was resistant to oxidation was 21% lower in P. cuspidatum-invaded soils and 50% higher in P. lobata-invaded soils. Our results highlight the capacity of invasive plants to feed back to climate change by destabilizing native soil C stocks and indicate that environments that promote the biochemical decomposition of plant litter would enhance the long-term storage of soil C. Further, our study highlights the concurrent influence of dominant plant species on both selective preservation and humification of soil organic matter.


Assuntos
Carbono/análise , Ecossistema , Fallopia japonica/crescimento & desenvolvimento , Pueraria/crescimento & desenvolvimento , Microbiologia do Solo , Solo/química , Biomassa , Ciclo do Carbono , Mudança Climática , Espécies Introduzidas , Massachusetts , South Carolina
14.
Sheng Wu Gong Cheng Xue Bao ; 30(10): 1573-85, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25726582

RESUMO

In order to study the effect of phytohormone on growth and isoflavones contents of Pueraria phaseoloides hairy roots, we cultured the hairy roots with different concentrations of 6-benzylaminopurine (6-BA) alone or in combination with α-naphthaleneacetic acid (NAA). Then we determined the effects of 6-BA alone or in combination with NAA on the growth and the contents of isoflavones compounds and levels of antioxidase activities of hairy roots by spectrophotometry. The results show that 6-BA inhibited the growth, and decreased biomass and total isoflavones compounds of P. phaseoloides hairy roots. Furthermore, the inhibition was increased with the concentrations of 6-BA. Compared with the controls, different concentrations of 6-BA in combination with NAA 2.0 mg/L could inhibit the growth of hairy roots and decrease the content of total isoflavone compounds, and also significantly enhanced the contents of soluble protein and levels of peroxidase (POD) activities, but decreased the activities of superoxide dismutase (SOD). DNA ladders detected by agarose gel electrophoresis can be observed after hairy roots of P. phaseoloides were cultured with 6-BA alone for 30 days, but can appear on the 20th day after culture with 6-BA in combination with NAA 2.0 mg/L. This result indicates that 6-BA or 6-BA in combination with NAA can both stimulate appearance of programmed cell death (PCD), and NAA may play a synergistic role on PCD.


Assuntos
Cinetina/farmacologia , Ácidos Naftalenoacéticos/farmacologia , Raízes de Plantas/crescimento & desenvolvimento , Pueraria/efeitos dos fármacos , Compostos de Benzil , Isoflavonas/química , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Pueraria/crescimento & desenvolvimento , Purinas
15.
Environ Entomol ; 42(5): 936-41, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24073651

RESUMO

Kudzu [Pueraria montana variety lobata (Willd.) Maesen & S. M. Almeida] plant architecture and growth were compared for plants subjected to 4 wk of simulated herbivory (75% leaf cutting) and no damage. Simulated herbivory reduced above-ground and root biomass by 40 and 47%, respectively, whereas total vine length and average length of the 10 longest vines were reduced by 48 and 43%, respectively, compared with control plants. Plant architecture was also affected, with damaged plants showing a significantly reduced proportion of primary vines, shorter secondary vines, and reduced average internode distances compared with the control plants. In natural situations, these changes would reduce the ability of kudzu to compete for light and other resources by affecting the plant's climbing habit.


Assuntos
Herbivoria , Insetos/fisiologia , Pueraria/anatomia & histologia , Pueraria/crescimento & desenvolvimento , Animais , Delaware , Cadeia Alimentar
16.
World J Microbiol Biotechnol ; 28(5): 1941-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22806015

RESUMO

The fungal plant pathogen, Myrothecium verrucaria, is highly virulent to several important weed species and has potential utility as a bioherbicide. However the production of macrocyclic trichothecene mycotoxins by this fungus presents significant safety concerns. It was discovered that trichothecenes are removed from M. verrucaria spores by repeated washes with water. These washed spores retained bioherbicidal efficacy against kudzu when tested in field trials and on sicklepod when tested under greenhouse conditions. Changes in the growth medium combined with washing spores with water resulted in greater than 95% reduction in roridin A and verrucarin A. Washing spores reduced trichothecene concentrations in spore preparations with no significant effect on plant biomass reduction, thus demonstrating the possibility of M. verrucaria formulations with improved safety to researchers, producers and applicators.


Assuntos
Herbicidas/isolamento & purificação , Hypocreales/química , Hypocreales/patogenicidade , Esporos/química , Esporos/patogenicidade , Biomassa , Pueraria/crescimento & desenvolvimento , Pueraria/microbiologia , Tricotecenos/isolamento & purificação
17.
Environ Entomol ; 41(1): 40-50, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22525058

RESUMO

The bean plataspid, Megacopta cribraria (F.), recently was discovered in the United States feeding on kudzu, Pueraria montana Lour. (Merr.) variety lobata (Willd.), an economically important invasive vine. We studied its biology on kudzu and its impact on kudzu growth. We also tested its ability to use other common forest legumes for oviposition and development. Flight intercept traps operated from 17 May 2010 to 31 May 2011 in a kudzu field near Athens, GA showed three peaks of adult flight activity suggesting there are two generations per year on kudzu. Vine samples examined for eggs from April 2010 to April 2011 and June to October 2011 showed two periods of oviposition activity in 2010, which coincided with the peaks in adult activity. In 2011, the second period of oviposition began on or before 24 June and then egg abundance declined gradually thereafter until late August when we recovered <2 eggs/0.5 m of vine. Samples of the five nymphal instars and adults on vines did not show similar trends in abundance. Adults did not lay eggs on the various legume species tested in 2010 in a no-choice test possibly because the cages were too small. In the 2011 field host range experiments conducted in a kudzu field by using 12 legume species, M. cribraria preferentially oviposited on kudzu over soybean, Glycine max Merrill., but they still laid 320 eggs per plant on soybean. Lespedeza hirta (L.) Hornem. and Lespedeza cuneata (Dum. Cours.) G. Don had 122.2 and 108.4 eggs per plant, respectively. Kudzu and soybean were the only species M. cribraria completed development on. Plots protected from M. cribraria feeding by biweekly insecticide applications had 32.8% more kudzu biomass than unprotected plots. Our results show that M. cribraria has a significant impact on kudzu growth and could help suppress this pest weed.


Assuntos
Agentes de Controle Biológico , Heterópteros/fisiologia , Oviposição , Pueraria/crescimento & desenvolvimento , Animais , Fabaceae/crescimento & desenvolvimento , Feminino , Preferências Alimentares , Georgia , Heterópteros/crescimento & desenvolvimento , Masculino , Ninfa , Óvulo , Estações do Ano
18.
Biotechnol Bioeng ; 109(1): 100-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21830206

RESUMO

Photosynthesis for the generation of fuels and chemicals from cyanobacteria and microalgae offers the promise of a single host organism acting both as photocatalyst and processor, performing sunlight absorption and utilization, as well as CO(2) assimilation and conversion into product. However, there is a need to develop methods for generating, sequestering, and trapping such bio-products in an efficient and cost-effective manner that is suitable for industrial scale-up and exploitation. A sealed gaseous/aqueous two-phase photobioreactor was designed and applied for the photosynthetic generation of volatile isoprene (C(5)H(8)) hydrocarbons, which operates on the principle of spontaneous diffusion of CO(2) from the gaseous headspace into the microalgal or cyanobacterial-containing aqueous phase, followed by photosynthetic CO(2) assimilation and isoprene production by the transgenic microorganisms. Volatile isoprene hydrocarbons were emitted from the aqueous phase and were sequestered into the gaseous headspace. Periodic replacement (flushing) of the isoprene (C(5)H(8)) and oxygen (O(2)) content of the gaseous headspace with CO(2) allowed for the simultaneous harvesting of the photoproducts and replenishment of the CO(2) supply in the gaseous headspace. Reduction in practice of the gaseous/aqueous two-phase photobioreactor is offered in this work with a fed-batch and a semi-continuous culturing system using Synechocystis sp. PCC 6803 heterologously expressing the Pueraria montana (kudzu) isoprene synthase (IspS) gene. Constitutive isoprene production was observed over 192 h of experimentation, coupled with cyanobacterial biomass accumulation. The diffusion-based process in gaseous/aqueous two-phase photobioreactors has the potential to be applied to other high-value photosynthetically derived volatile molecules, emanating from a variety of photosynthetic microorganisms.


Assuntos
Butadienos/metabolismo , Dióxido de Carbono/metabolismo , Hemiterpenos/metabolismo , Pentanos/metabolismo , Fotobiorreatores/microbiologia , Fotossíntese , Pueraria/fisiologia , Synechocystis/fisiologia , Butadienos/química , Dióxido de Carbono/química , Difusão , Hemiterpenos/química , Montana , Organismos Geneticamente Modificados/crescimento & desenvolvimento , Organismos Geneticamente Modificados/metabolismo , Organismos Geneticamente Modificados/fisiologia , Pentanos/química , Pueraria/crescimento & desenvolvimento , Pueraria/metabolismo , Synechocystis/crescimento & desenvolvimento , Synechocystis/metabolismo
19.
Proc Natl Acad Sci U S A ; 107(22): 10115-9, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20479252

RESUMO

The nitrogen-fixing legume kudzu (Pueraria montana) is a widespread invasive plant in the southeastern United States with physiological traits that may lead to important impacts on ecosystems and the atmosphere. Its spread has the potential to raise ozone levels in the region by increasing nitric oxide (NO) emissions from soils as a consequence of increasing nitrogen (N) inputs and cycling in soils. We studied the effects of kudzu invasions on soils and trace N gas emissions at three sites in Madison County, Georgia in 2007 and used the results to model the effects of kudzu invasion on regional air quality. We found that rates of net N mineralization increased by up to 1,000%, and net nitrification increased by up to 500% in invaded soils in Georgia. Nitric oxide emissions from invaded soils were more than 100% higher (2.81 vs. 1.24 ng NO-N cm(-2) h(-1)). We used the GEOS-Chem chemical transport model to evaluate the potential impact of kudzu invasion on regional atmospheric chemistry and air quality. In an extreme scenario, extensive kudzu invasion leads directly to an increase in the number of high ozone events (above 70 ppb) of up to 7 days each summer in some areas, up from 10 to 20 days in a control scenario with no kudzu invasion. These results establish a quantitative link between a biological invasion and ozone formation and suggest that in this extreme scenario, kudzu invasion can overcome some of the air quality benefits of legislative control.


Assuntos
Poluentes Atmosféricos/metabolismo , Óxido Nítrico/metabolismo , Ozônio/metabolismo , Pueraria/crescimento & desenvolvimento , Pueraria/metabolismo , Poluição do Ar , Conservação dos Recursos Naturais , Ecossistema , Georgia , Modelos Biológicos , Fixação de Nitrogênio
20.
Zhongguo Zhong Yao Za Zhi ; 33(19): 2175-9, 2008 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-19165999

RESUMO

OBJECTIVE: To study the tissue culture and rapid-proliferation techniques of Pueraria mirifica. METHOD: The tender branch were used as explants and cultivated in different media. The optimum media for inducing buds, proliferation and rooting were selected by adjusting the kinds and doses of plant hormones and special compounds. RESULT: The medium of MS + IBA 0.05 mg L(-1) + BA 0.5 mg L(-1) was suitable for buds inducing and could be used in the first generation cultivation; MS + IBA 0. 02 mg L(-1) + BA 0.2 mg L(-1) and MS +BA 0.1 mg L(-1) were employed by turns in subculture, 25 days propagation coefficient was 3.0; and the medium of 1/2MS + IBA 0.1 mg L(-1) + IAA 0.2 mg L(-1) + C (special compound) 10 mg L(-1) was used for roots inducing, the rooting rate was 76.9%. Rooting plantlets were transplanted in spring and summer; the surviving rate was 81.0%. CONCLUSION: This technique system could be employed for rapid propagation of P. mirifica.


Assuntos
Pueraria/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos/métodos
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