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1.
Jan S Parween T Siddiqi TO Mahmooduzzafar 《Radiation and environmental biophysics》2012,51(3):341-347
Gamma irradiation of seeds is known to be an important factor in stimulating biochemical and physiological processes. The aim of the present study was to investigate phenylpropanoids and associated enzymes responsible for the production of active metabolites. Furanocoumarin content was estimated in seeds of Psoralea corylifolia L. during two successive generations (G(1) and G(2)) where as phenylalanine ammonia lyase (PAL) activity was measured in leaves at different developmental stages of P. corylifolia L. raised from seeds irradiated with variable doses of gamma rays. Maximum accumulation of psoralen and isopsoralen was observed at 15 and 20 kGy doses during G(1) and G(2) generations, respectively. Psoralen proved to be the dominating metabolite in terms of its concentration, while isopsoralen was accumulated at relatively lower concentrations in successive generations. PAL activity was induced maximally following 15 and 20 kGy in G(1) plants and was preceded by psoralen and isopsoralen accumulation which peaked at the same dose rates in both generations. These effects were transmitted and prevalent in the next generation, that is, G(2) (indirectly irradiated). These long-term changes in plant metabolomics demonstrate genomic instability induced by gamma irradiation. However, no detrimental effects were seen at any irradiation dose in seeds. Furanocoumarin concentrations were also enhanced at 15 and 20 kGy. The present study further points out the persistence of changes in the biosynthesis of coumarin derivatives in the next generation. However, accumulation of these metabolites does not lead to any lethal effects. 相似文献
2.
Psoralea corylifolia is an attractive, endangered annual producing various bioactive compounds of medical importance. This plant contributes to
Indian pharmaceutical and cosmetic industries for the production of commercial medicines, Ayurvedic skin care ointments and
soap. The influence of various plant growth regulators (PGRs) and additives on high-frequency rapid adventitious shoot regeneration
from transverse thin cell layer (tTCL) hypocotyl explants of P. corylifolia was investigated. Organogenic callus was obtained in tTCL hypocotyl explants on Murashige and Skoog (1962) medium supplemented with 15 μM naphthaleneacetic acid (NAA) and 3 μM benzylaminopurine (BA). The highest adventitious shoot
regeneration (107.5 shoots per explant) was achieved in culture when transferred to half-strength solid MS medium. The regenerated
shoots were rooted and the plantlets successfully acclimatized in moistened (1/8-MS basal salt solution with 3 μM indole-3-butyric
acid (IBA), 1 μM 2-isopentenyladenine (2iP) and 100 mg l−1 Bavistin (BVN)); garden soil, farmyard soil and sand (2:1:1, v/v/v). The acclimatized plants produced flowers in the growth
chamber. When planted in the field these plants set viable seed. The psoralen content in different tissues of ex vitro and naturally-grown plants was determined by high-performance liquid chromatography (HPLC). The highest psoralen content
was recorded in seeds from naturally-grown (6.48 μg g−1 DW) and ex vitro plants (6.46 μg g−1 DW). This system can be used for rapid mass propagation of P. corylifolia, for conservation strategies, and to produce phytomedicines. 相似文献
3.
《Journal of receptor and signal transduction research》2013,33(1):39-44
The present work was carried out to determine the effects of lyophilized seed extracts of Psoralea corylifolia along with pure psoralen, its active ingredient on the isolated tail-piece melanophores of Bufo melanostictus, a type of disguised smooth muscle cells, which offer excellent in vitro opportunities for studying the effects of pharmacological and pharmaceutical agents. In the present study, it was found that lyophilized extract of P. corylifolia and its active ingredient psoralen induced powerful, dose-dependent, physiologically significant melanin dispersal effects in the isolated tail melanophores of B. melanostictus, which were completely blocked by atropine as well as hyoscine. The per se melanin dispersal effects of lyophilized extracts of P. corylifolia and its active ingredient psoralen were highly potentiated by neostigmine. It appears that the melanin dispersal effects of the extracts of P. corylifolia and psoralen are mediated by cholino-muscarinic or cholino-psoralen like receptors having similar properties that need to be studied further. 相似文献
4.
The availability of soil and pollination resources are main determinants of fitness in many flowering plants, but the degree
to which each is limiting and how they interact to affect plant fitness is unknown for many species. We performed resource
(water and nutrients) and pollination (open and supplemental) treatments on two species of flowering plants, Ipomopsis aggregata and Linum lewisii, that differed in life-history, and we measured how resource addition affected floral characters, pollination, and reproduction
(both male and female function). We separated the direct effects of resources versus indirect effects on female function via
changes in pollination using a factorial experiment and path analysis. Resource addition affected I. aggregata and L. lewisii differently. Ipomopsis aggregata, a monocarp, responded to fertilization in the year of treatment application, increasing flower production, bloom duration,
corolla width, nectar production, aboveground biomass, and pollen receipt relative to control plants. Fertilization also increased
total seed production per plant, and hand-pollination increased seeds per fruit in I. aggregata, indicating some degree of pollen limitation of seed production. In contrast, fertilization had no effect on growth or reproductive
output in the year of treatment on L. lewisii, a perennial, except that fertilization lengthened bloom duration. However, delayed effects of fertilization were seen in
the year following treatment, with fertilized plants having greater aboveground biomass, seeds per fruit, and seeds per plant
than control plants. In both species, there were no effects of resource addition on male function, and the direct effects
of fertilization on female function were relatively stronger than the indirect effects via changes in pollination. Although
we studied only two plant species, our results suggest that life-history traits may play an important role in determining
the reproductive responses of plants to soil nutrient and pollen additions. 相似文献
5.
C. Arena E. Vitale B. Hay Mele P. R. Cataletto M. Turano P. Simoniello V. De Micco 《Plant biology (Stuttgart, Germany)》2019,21(4):615-626
- The realisation of manned space exploration requires the development of Bioregenerative Life Support Systems (BLSS). In such self‐sufficient closed habitats, higher plants have a fundamental role in air regeneration, water recovery, food production and waste recycling. In the space environment, ionising radiation represents one of the main constraints to plant growth.
- In this study, we explore whether low doses of heavy ions, namely Ca 25 Gy, delivered at the seed stage, may induce positive outcomes on growth and functional traits in plants of Solanum lycopersicum L. ‘Microtom’. After irradiation of seed, plant growth was monitored during the whole plant life cycle, from germination to fruit ripening. Morphological parameters, photosynthetic efficiency, leaf anatomical functional traits and antioxidant production in leaves and fruits were analysed.
- Our data demonstrate that irradiation of seeds with 25 Gy Ca ions does not prevent achievement of the seed‐to‐seed cycle in ‘Microtom’, and induces a more compact plant size compared to the control. Plants germinated from irradiated seeds show better photochemical efficiency than controls, likely due to the higher amount of D1 protein and photosynthetic pigment content. Leaves of these plants also had smaller cells with a lower number of chloroplasts. The dose of 25 Gy Ca ions is also responsible for positive outcomes in fruits: although developing a lower number of berries, plants germinated from irradiated seeds produce larger berries, richer in carotenoids, ascorbic acid and anthocyanins than controls.
- These specific traits may be useful for ‘Microtom’ cultivation in BLSS in space, in so far as the crew members could benefit from fresh food richer in functional compounds that can be directly produced on board.
6.
The tolerance of Musa balbisiana Colla seeds to gamma irradiation was found to be considerably greater than that of rhizomes of the parthenocarpic variety ‘Gros Michel': e.g., 11.8 krad reduced the germination of rhizomes 92% and of seeds approximately 15%. Intact seeds exposed to doses higher than 48 krad did not germinate in non-sterile soil, but, when scarified and cultured axenically after irradiation, seeds which received doses as high as 70 krad germinated. Embryos excised from seeds exposed to doses as high as 285 krad formed callus, indicating that not all metabolic processes were inhibited by these extremely high doses. There was considerable variation in radiation tolerance between seed lots which was not related to their age, moisture content, or pre-exposure viability. Germination of intact seeds appeared to be stimulated by doses of 3 or 9 krad. No lasting differences attributable to the level of irradiation were apparent in the development of seedlings derived from either intact or scarified seeds nor of plantlets derived from excised embryos. Conversely, there was a significant reduction, proportional to irradiation dose, in the growth of plants developing from rhizomes, emphasizing the greater radiation sensitivity of the vegetative propagule. The radiation tolerance of seed-borne microorganisms was considerably higher than that of the plant materials, indicating that gamma irradiation is not effective as a means of obtaining pathogen-free rhizomes or surface-sterilizing seeds of M. balbisiana. 相似文献
7.
Nitrogen (N) has been suggested as a determinant of seed production especially in species with high seed N content. Assuming
that seed yield was determined as the balance between N demand and supply for seed production, we studied the effect of N
fertilization after flowering on soybean (Glycine max L. Merr.) yield. Seed N concentration was nearly constant irrespective of N fertilization, indicating that seed production
was proportional to the amount of N available for seed growth. N demand for seed production was analyzed as the product of
seed number, the rate of N filling in individual seeds, and the length of the reproductive period. N fertilization increased
seed number and the reproductive period, but did not influence the N filling rate. Seed number was positively correlated with
dry mass productivity after flowering. Three N sources were distinguished: mineral N uptake, symbiotic N2 fixation and N remobilization from vegetative body. N fertilization increased N uptake and N remobilization, but lowered
N2 fixation. We concluded that N availability in the reproductive period determined seed yield directly through increasing N
supply for seed growth and indirectly through increasing seed N demand with enhanced plant dry mass productivity. 相似文献
8.
Effects of season and population size on pollination and reproductive output in a Mediterranean shrub
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A. M. Sánchez M. Rodríguez M. J. Albert A. Escudero 《Plant biology (Stuttgart, Germany)》2017,19(3):428-437
- Pollinator guilds may change throughout extended flowering periods, affecting plant reproductive output, especially in seasonal climates. We hypothesised a seasonal shift in pollinator guild and an autumn reduction in pollinator abundance, especially in small and sparse populations.
- We recorded pollinator identity, abundance and behaviour in relation to flower density from plant to population throughout the extended flowering of Ononis tridentata. We evaluated female reproductive output by recording pollination success and pre‐dispersal seed predation in eight populations of contrasting size and density. Offspring quality was also characterised through seed weight and germination.
- A diverse guild of insects visited O. tridentata in spring, while only Apis mellifera was observed in autumn. Visitation frequency did not vary seasonally, but the number of flowers per foraging bout was lower, and seeds were heavier and had a higher germination rate in autumn. Plant and neighbourhood flowering display were not related to pollinator visitation frequency or behaviour. However, the rate of fertilised ovules, seed set and autumn flowering display size were positively related to population density.
- The maintenance of pollination in autumn enhances the reproductive performance of O. tridentata due to higher quality of autumn seed, and to a large reduction in seed predator pressure. We also suggest that observed changes in pollinator behaviour could be one of the processes behind seasonal variation in seed performance, since geitonogamous crosses were less likely to occur in autumn.
9.
Gupta Prakash C. Bajpai Vivek Mishra V. Saxena R. K. Singh Surendra 《World journal of microbiology & biotechnology》2009,25(12):2267-2271
The effects of gamma irradiation on microbial load, total aflatoxins and phytoconstituents content of Trigonella foenum-graecum have been studied. Gamma irradiation at a dose of 2.5 kGy resulted in 2 log reduction of the total aerobic microbial count.
A complete sterilization was, however, observed at 10 kGy. The total aflatoxin level decreased gradually with increase in
gamma irradiation dose as compared to its un-irradiated counterparts, whereas the high performance liquid chromatography (HPLC)
profile showed no change in the levels of phytochemicals up to the gamma irradiation dose of 10 kGy. HPLC profiles, however,
differed in peak areas, and retention times of the components. These results suggest that gamma irradiation at a dose of 5.0 kGy
was very effective for microbial decontamination because it did not adversely affect the active components of T. foenum-graecum. 相似文献
10.
Sporotrichosis is a subcutaneous mycosis caused by Sporothrix schenckii. Zoonotic transmission to man can occur after scratches or bites of animals, mainly cats. In this study, the gamma radiation
effects on yeast of S. schenckii were analyzed with a view of developing a radioattenuated vaccine for veterinary use. The cultures were irradiated at doses
ranging from 1.0 to 9.0 kGy. The reproductive capacity was measured by the ability of cells to form colonies. No colonies
could be recovered above 8.0 kGy, using inocula up to 107 cells. Nevertheless, yeast cells irradiated with 7.0 kGy already were unable to produce infection in immunosuppressed mice.
Evaluation by the FungaLight™ Kit (Invitrogen) indicated that yeast cells remained viable up to 9.0 kGy. At 7.0 kGy, protein
synthesis, estimated by the incorporation of [L-35S] methionine, continues at levels slightly lower than the controls, but a significant decrease was observed at 9.0 kGy. The
DNA of 7.0 kGy irradiated cells, analyzed by electrophoresis in agarose gel, was degraded. Cytoplasmic vacuolation was the
main change verified in these cells by transmission electron microscopy. The dose of 7.0 kGy was considered satisfactory for
yeast attenuation since irradiated cells were unable to produce infection but retained viability, metabolic activity, and
morphology. 相似文献
11.
Psoralea corylifolia is an endangered plant producing various compounds of medical importance. Adventitious roots and hairy roots were induced
in cultures prepared from hypocotyl explants. Psoralen content was evaluated in both root types grown either in suspension
cultures or on agar solidified medium. Psoralen content was ~3 mg g−1 DW in suspension grown hairy roots being higher than in solid grown hairy roots and in solid and suspension-grown adventitious
roots. 相似文献
12.
Plant species variation in bottom‐up effects across three trophic levels: a test of traits and mechanisms
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XOAQUÍN MOREIRA LUIS ABDALA‐ROBERTS JOHNATTAN HERNÁNDEZ‐CUMPLIDO SERGIO RASMANN SARAH G. KENYON BETTY BENREY 《Ecological Entomology》2015,40(6):676-686
1. An increasing number of studies have addressed the mechanisms by which plant inter‐specific variation influence interactions at higher trophic levels, but little is known about the underlying plant traits driving these dynamics. 2. Here we investigated the effects of host plant species on herbivore‐parasitoid interactions and the underlying traits driving such effects. For this, we measured the abundance of seed‐eating bruchids and their parasitoids across seven sympatric populations of the bean species Phaseolus coccineus and Phaseolus vulgaris in Central Mexico. To investigate the mechanisms underlying differences between bean species in bruchid‐parasitoid interactions, we carried out two laboratory experiments to test whether bruchid and parasitoid performance differed between plant species. We also measured seed size and phenolic compounds to investigate if seed traits mediate bruchid‐parasitoid interactions by influencing herbivore susceptibility or resistance to parasitoids. 3. Field surveys revealed that the rate of parasitoid recruitment to bruchids was significantly higher on P. vulgaris than on P. coccineus. Subsequent laboratory bioassays indicated that bruchids developed more slowly and exhibited lower fitness on P. vulgaris seeds than on P. coccineus seeds. Accordingly, we found that bean species differed in seed size, with P. vulgaris having smaller (less nutritious) seeds, which explains why bruchid development was slower on this plant species. 4. These results provide a mechanism for why bruchids exhibited higher parasitism rates on seeds of P. vulgaris in the field which could be due to Slow‐Growth/High‐Mortality effects, a smaller physical refuge provided by the seed, or both factors. The roles of these mechanisms remain inconclusive without further study. 相似文献
13.
Euphorbia pedroi is a narrow endemic species with three known populations located in coastal areas of western Portugal. This study focused
on the reproductive biology of this species from flowering to dispersal, aiming to identify the factors causing decrease in
seed production potential and to assess the spatio-temporal patterns of seed production at the individual and population levels.
The abortion of reproductive structures, particularly seeds, represented a major fraction of losses in the potential seed
production of E. pedroi. Moth larvae destroyed a variable proportion of cyathia in a large number of plants from the two populations regardless of
their degree of isolation. Furthermore, generalist and specialist pre-dispersal seed predators were responsible for temporally
variable seed losses unrelated with variables indicative of plant size and fecundity, and showing no consistency at the individual
level. Specialist seed-wasps inflicted the highest losses to E. pedroi and their impact was intimately associated with the magnitude of yearly variation in seed production. This finding highlights
the role of the inter-annual variation in seed production as a key feature in this plant-seed predator system. The effect
of the two groups of seed predators on the reproductive output of E. pedroi was additive and those insects do not seem to exert an important selective pressure on the traits studied. The proportion
of intact seeds produced by E. pedroi differed between locations, but not between individuals within each population, highlighting the major contribution of larger
plants to the seed pool. 相似文献
14.
Fragment size does not matter when you are well connected: effects of fragmentation on fitness of coexisting gypsophiles
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S. Matesanz A. Gómez‐Fernández I. Alcocer A. Escudero 《Plant biology (Stuttgart, Germany)》2015,17(5):1047-1056
Most habitat fragmentation studies have focused on the effects of population size on reproductive success of single species, but studies assessing the effects of both fragment size and connectivity, and their interaction, on several coexisting species are rare. In this study, we selected 20 fragments along two continuous gradients of size and degree of isolation in a gypsum landscape in central Spain. In each fragment, we selected 15 individuals of each of three dominant gypsophiles (Centaurea hyssopifolia, Lepidium subulatum and Helianthemum squamatum, 300 plants per species, 900 plants in total) and measured several reproductive traits: inflorescence number, fruit set, seed set and seed mass. We hypothesised that plant fitness would be lower on small and isolated fragments due to an interaction between fragment size and connectivity, and that response patterns would be species‐specific. Overall, fragment size had very little effect on reproductive traits compared to that of connectivity. We observed a positive effect of fragment connectivity on C. hyssopifolia fitness, mediated by the increased seed predation in plants from isolated fragments, resulting in fewer viable seeds per capitulum and lower seed set. Furthermore, seed mass was lower in plants from isolated fragments for both C. hyssopifolia and L. subulatum. In contrast, few reproductive traits of H. squamatum were affected by habitat fragmentation. We discuss the implications of species‐specific responses to habitat fragmentation for the dynamics and conservation of gypsum plant communities. Our results highlight the complex interplay among plants and their mutualistic and antagonistic visitors, and reinforce the often‐neglected role of habitat connectivity as a key component of the fragmentation process. 相似文献
15.
Esmaeil Bakhshandeh Fatemeh Hosseini Sanehkoori Hamidreza Ghorbani Ghorban Ali Nematzadeh Mansour Sekrafi Raoudha Abdellaoui Mohammad Yaghoubi Khanghahi Carmine Crecchio 《The Annals of applied biology》2023,183(1):23-32
To date, there has been little agreement on supporting the hypothesis that how some key vegetative traits of camelina (Camelina sativa (L.) Crantz var. ‘Soheil’) are dependent on plant biomass. Therefore, the main aim of this investigation was to quantify the relationship between the size of camelina plants and seed production across a broad-range of plant densities through modelling approaches. To make a wide range of plant densities, a fan design was used in eight replicates in an experimental field at Sari Agricultural Sciences and Natural Resources University, Iran. To quantify the relation between plant density and other plant traits, a regression analysis was carried out and the coefficient of determination (R2) was considered to evaluate the goodness of fit model. A power model (y = axb) could describe well the relationship between plant density (ranged 113–2905 plants m−2) and plant biomass, seed production, number of seeds per plant, stem diameter, and siliques number, with the coefficient of determination (R2) values of 0.85, 0.87, 0.65, 0.64, and 0.90, respectively. The harvest indexes were 13.8%–26.9%, depending on plant density. Seed production per plant was positively correlated to the siliques number (r = 0.85), the branch number (r = 0.80), and the seed number (r = 0.99) which could be key components of camelina seed production per plant. Furthermore, no significant correlation was found among plant height, thousand-seed weight, and harvest index with seed production per plant. In conclusion, plant biomass could be considered an important trait to predict plant growth models of camelina. Also, a lower plant density of camelina can be compensated by a greater number of siliques, branches and seeds per plant. 相似文献
16.
Richard B. Primack Ann R. Rittenhouse Peter V. August 《American journal of botany》1981,68(6):855-858
Four components of reproductive yield (the weight of reproductive tissue) were examined in relation to their effect on reproductive effort and their relative contributions to reproductive yield in five species of goldenrods (Solidago, Compositae). The yield components were number of flowing stems per plant, number of flowering branches per stem, number of flowering heads per branch, and number of seeds per seed head. Individuals within populations increase their reproductive effort by increasing their reproductive weight, not by decreasing their vegetative weight. Each species shows a different pattern of positive correlations of yield components with reproductive yield and reproductive effort, indicating that each species has its own mechanisms for regulating reproduction. The yield components were not significantly intercorrelated. 相似文献
17.
A rapid and efficient micropropagation system was developed for Psoralea corylifolia, an endangered, valuable medicinal plant. Multiple shoot buds were obtained in half-strength liquid Phillips–Collins (L2)
medium supplemented with 5 μM benzylaminopurine (BA) and 5 μM thidiazuron (TDZ) from apical bud explants of 1-week-old cultures.
The shoot buds were subcultured on enriched solid L2 medium supplemented with different concentrations and combinations of
BA, kinetin (KIN), 2-isopentenyladenine (2iP), TDZ, bavistin (BVN) and trimethoprim (TMP). Enriched solid L2 medium supplemented
with 2 μM BA, 1 μM TDZ and 100 mg l−1 BVN were more effective in producing greater number of shoots per explant (85.2 ± 0.9 shoots/explant) after 4 weeks of culture.
The regenerated shoots (40–50 mm in length) rooted and accompanied by hardening upon transfer to 50 μM indole-3-butyric acid
(IBA) for 15 min and followed by planting in sterile soil mixture and vermiculate (3:1 v/v), with 50 ml of one-eight strength
L2 basal salt solution devoid of sucrose and inositol, supplemented with 5 μM IBA and 100 mg l−1 BVN. The plants achieved 100% rooting with hardening. Subsequently the rooted plants were successfully established in the
field. The survival percentage differed with seasonal variations. The concentration of psoralen was evaluated in different
tissues of ex vitro and in vivo grown plants by high-performance liquid chromatography (HPLC). Psoralen content was increased
in leaves (2.97%), roots (2.38%), stems (5.40%) and seeds (1.63%) of ex vitro plants than the in vivo plants. This system
facilitates for commercial and rapid propagation of P. corylifolia for conservation strategies and phytomedicine production. 相似文献
18.
Abstract. We analysed the relationship between seed traits (weight, shape and dispersal structures) and the abundance and habitat segregation of Mediterranean grassland species. To take into account possible correlations with other plant traits, the study also includes 5 vegetative traits (growth form, plant longevity, clonality, onset of flowering and plant size) of commonly accepted functional importance. Data were recorded for 85 species from dehesa grasslands in central Spain. Species abundance was measured in upper (dry and less productive, high stress) and lower (moist and more productive, low stress) slope zones in the same area. Habitat segregation was estimated using an index based on the relative frequencies of species in upper and lower slope zones. Multiple regression models were fitted using species, as well as phylogenetically independent contrasts, as data points. Annual small‐seeded species without specialised dispersal structures are over‐represented in dehesa grasslands. Abundance was negatively related to seed weight in upper slope zones. None of the recorded plant traits were related to abundance in the lower slope zones. Habitat segregation was mainly related to seed weight, but also to some vegetative traits. Annual, early flowering and small‐seeded species were relatively more abundant in the upper than the lower slope zones. This pattern is independent of phylogeny. Our results suggest that in dry Mediterranean grasslands, abundance of many species is determined by dispersal (production of numerous small seeds) rather than by competitive ability. 相似文献
19.
Marco A. Molina-Montenegro Gabriel I. Ballesteros Ian S. Acuña-Rodríguez Luis R. Pertierra Michelle Greve David M. Richardson Peter Convey Elisabeth M. Biersma William P. Goodall-Copestake Kevin K. Newsham 《Diversity & distributions》2023,29(11):1432-1444
Aim
Poa annua L. (annual bluegrass) is presently the sole invasive vascular plant species to have successfully established in Maritime Antarctica, where it poses a significant conservation threat to native plant species. However, the reasons for its success in the region have yet to be established. Here, we determined whether the invasiveness of P. annua, and its competitiveness with the native Antarctic hairgrass Deschampsia antarctica, is influenced by symbioses formed with seed fungal endophytes, and whether plants derived from seeds from four global regions differ in their performance.Locations
Four regions (Maritime Antarctica, sub-Antarctica, South America and Europe).Methods
Endophyte frequency was measured in P. annua seeds collected from the four regions. The germination, survival, biomass accumulation, flowering and competitiveness with D. antarctica of P. annua plants grown from endophyte-uncolonised and uncolonised seeds was determined in the laboratory. The effects of endophytes on P. annua seed germination and survival and seedling osmoprotection were also assessed in the Maritime Antarctic natural environment using locally-sourced seeds.Results
Endophytes were at least twice as frequent in seeds from Maritime Antarctica than in those from other regions. A higher proportion of endophyte-colonized seeds germinated and survived than did uncolonised seeds, but only when they originated from Maritime Antarctica. Seed endophytes increased the competitiveness of P. annua with D. antarctica, but only for plants grown from Maritime Antarctic seeds. In the field, endophyte-colonized seeds from Maritime Antarctica germinated and survived more frequently than uncolonised seeds, and osmoprotection was higher in seedlings grown from colonized seed.Main Conclusions
The findings indicate beneficial effects of seed endophytes on invasion-related traits of P. annua, such as survival, germination success and flowering. Together with vegetative and reproductive traits facilitating the colonization process, the seed-fungal endophyte symbiosis can be invoked as an important factor explaining the invasiveness of P. annua in Maritime Antarctica. 相似文献20.
Chiba seed (Psoralea corylifolia L.) oil, which contains bioactive components such as bakuchiol, psoralen, and isosporalen, is recognized for its high medicinal
value and is widely used in Chinese and Indian Ayurvedic medicinal systems. Several earlier studies have proved the antibacterial
and antioxidant properties of the key components in the seed oil. In view of the importance of the bioactive components in
the global market, this study was carried out to separate the key components by supercritical carbon dioxide extraction and
further enrichment by the molecular distillation technique. The effects of the process variables such as pressure (400∼2,000
μm), temperature (140∼200°C), and wiper speed (120∼200 rpm) were studied based on response surface methodology. The predicted
model was maximized for the bakuchiol content in the distillate. And a predicted maximum of 72% bakuchiol content was confirmed
by the experiment under the optimized process conditions. 相似文献