Wedelia Trilobata Research Articles

Effects of Plant Leaf Extract against Colletotrichum gloeosporioides (Penz) Sac. Causing Post-Harvest Disease of Papaya

The antifungal activity of selected weed and other plants leaf extract prepared in distilled water and ethanol were tested against anthracnose, the post-harvest disease of papaya (Carica papaya L.) caused by Colletotrichum gloeosporioides. The result from the experiment proved that ethanol leaf extract of weed plant, Lantana camara L.possess significant fungicidal effect on the radial growth of C. gloeosporioides followed by lemon and avocado leaf extract while Mikania micrantha Kunth, Sphagneticola trilobata (L.) Pruski and Cyperus rotundus L. leaf extract gave an insignificant inhibitory effect on the radial growth the fungus. The result of this study showed that Lantana camara leaf extract has the potential antifungal compound to control C. gloeosporioides which is the casual organism of papaya anthracnose.

四种入侵植物提取液对褐云玛瑙蜗牛的防控效果

PDF HTML阅读 XML下载 导出引用 引用提醒 四种入侵植物提取液对褐云玛瑙蜗牛的防控效果 DOI: 10.5846/stxb201309092238 作者: 作者单位: 韩山师范学院生物系 广东 潮州 521041,韩山师范学院生物系 广东 潮州 521041,韩山师范学院生物系 广东 潮州 521041,韩山师范学院生物系 广东 潮州 521041,韩山师范学院生物系 广东 潮州 521041,韩山师范学院生物系 广东 潮州 521041 作者简介: 通讯作者: 中图分类号: Q143 基金项目: 广东省科技计划项目(2011B050300018);高等学校学科建设专项资金项目[粤财政(2007)129号] Effects of prevention and control of extracting solution from four invasive plants on Achatina Fulica Author: Affiliation: Biology Department,Hanshan Normal University,Chaozhou 52104 China,Biology Department,Hanshan Normal University,Chaozhou 52104 China,Biology Department,Hanshan Normal University,Chaozhou 52104 China,Biology Department,Hanshan Normal University,Chaozhou 52104 China,Biology Department,Hanshan Normal University,Chaozhou 52104 China,Biology Department,Hanshan Normal University,Chaozhou 52104 China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:实验室内观察了4种入侵植物水提取液对褐云玛瑙蜗牛成体和幼体的触杀及抑制蜗牛卵发育效果的差异性。结果表明:(1)以1.0 g/mL薇甘菊和南美蟛蜞菊水提取液对蜗牛喷杀处理, 对蜗牛触杀的有效时间分别为82 h和118 h;马樱丹触杀蜗牛的致死时间和有效时间最慢,4种入侵植物水提取液对成体褐云玛瑙蜗牛触杀效果强弱顺序为:薇甘菊 > 南美蟛蜞菊 > 五爪金龙 > 马缨丹。(2)1.0 g/mL 的4种入侵植物水取液对幼体蜗牛触杀的有效时间比成体蜗牛缩短2倍以上,幼体蜗牛个体死亡数量呈急剧增加趋势, 而成体蜗牛个体死亡数量呈相对平缓的增加趋势。(3)1.0、1.5 g/mL及2.0 g/mL薇甘菊水提取液对成体蜗牛触杀效果差异显著(P < 0.05)。以2.0 g/mL薇甘菊水提取液触杀蜗牛的有效时间最短, 与10%的四聚乙醛处理组相当, 为78 h, 显著少于1.5 g/mL的96 h和1.0 g /mL 的130 h。(4)褐云玛瑙蜗牛卵发育对1.0 g/mL 的4种入侵植物水提取液的干扰表现更为敏感。1.0 g/mL的薇甘菊水提取液抑制蜗牛卵发育的效果最好, 抑制率达81.67%,且与其它处理组间存在显著差异(P < 0.05)。而1.0 g/mL的马缨丹提取液优于五爪金龙提取液对褐云玛瑙蜗牛卵的抑制效果则表明入侵植物内源次生成分对不同发育时期的动物的防控效果存在差异。1.0 g/mL入侵植物水提取液各处理组对褐云玛瑙蜗牛卵发育抑制效果由强至弱的顺序为:薇甘菊 > 南美蟛蜞菊 > 马缨丹 > 五爪金龙。总之, 4种入侵植物对褐云玛瑙蜗牛成体、幼体和卵均具有较好的触杀与抑制作用, 利用入侵植物防控入侵动物, 以害制害, 化害为利, 是一种具有良好应用前景的环境友好型生物防治措施。 Abstract:Botanical pesticides have many advantages, including high efficiency, low toxicity, and environment friendliness. South China has large numbers of various invasive plants that are fast growing. Therefore, it is difficult to effectively control the proliferation and spreading of the invasive populations. It has been shown that invasive plants typically contain abundant secondary metabolites with strong physiological activities, such as terpenes, alkenes, lactones, flavonoids, and volatile oils. Adequate research on invasive plants might promote the development, controlled growth, and utilization of invasive plants as botanical pesticides, thereby converting the harm that they cause into significant economical and ecological benefits. Achatina fulica, which originated in East Africa, is a Class II harmful alien organism according to General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China (AQSIQ). Currently, A. fulica is widespread in South China and has shown strong reproductive ability and fast population diffusion, causing severe damages to vegetables and crops, as well as the natural ecosystem. In this study, we collected wild A. fulica and reared them in the lab. Further, the water extracts of four major invasive plants in southern China-Mikania micrantha, Wedelia trilobata, Ipomoea cairica, and Lantana camara-were prepared and their individual contact toxicities on A. fulica larvae and adults and inhibiting effects on egg development were compared. The comparison results were used to evaluate the prevention and control effects of the 4 invasive plants on A. fulica, as part of the primary screening of snail-restricting plants. The results showed the following: (1) Spraying 1.0 g/mL water extracts of Mikania micrantha and Wedelia trilobata on Achatina Fulica has fastest killing effect, the snail contact killing times were 82 h and 118 h, respectively; Lantana camara showed the longest killing time and effective time of snail contact killing. The order of snail killing effects of the 4 invasive plant water extracts is Mikania micrantha > Wedelia trilobata > Ipomoea cairica > Lantana camara. (2) The 1.0 g/mL water extracts showed highly significant contact-killing effects on snail larvae. However, more than twice lower contact killing times of each treatment were noted on the adult snails than on the larvae. A sharp increasing trend was noted in the number of dead larvae, whereas a relatively slower increasing trend was observed for the number of dead adults. (3) The 1.0, 1.5, and 2.0 g/mL M. micrantha water extracts showed significantly different contact-killing effects on adult snails (P < 0.05), where high-concentration M. micrantha water extract had short contact killing time-2.0 g/mL had the shortest effective contact killing time of 78 h, which was equivalent to that of 10% metaldehyde and significantly less than the 96 h with 1.5 g/mL and 130 h with 1.0 g/mL extract. (4) The egg development of A. fulica was highly sensitive to 1.0 g/mL water extracts of the 4 invasive plants, among which 1.0 g/mL M. micrantha water extract showed the best inhibiting effect as high as 81.67% (P< 0.05). Further, 1.0 g/mL L. camara water extract showed better inhibiting effect on the eggs of A. fulica than of I. cairica, indicating that endogenous secondary compositions in the invasive plant extracts have different prevention and control effects on animals at different development stages. The order of inhibiting effects of 1.0 g/mL water extracts of the 4 invasive plants on A. fulica eggs in the order of the strongest to the weakest was as follows: M. micrantha > W. trilobata > L. camara > I. cairica. In conclusion, all 4 invasive plants showed good contact killing and inhibiting effects on the adult, larva, and egg of A. fulica. Thus, using invasive plants to prevent and control invasive animals is an environment friendly measure for biological prevention and control and has great application prospects. 参考文献 相似文献 引证文献

Distribution patterns of alien invasive plants and their influences on native plants of Hainan Island

Aims Our objective was to explore the distribution patterns of 20 noxious invasive plants in Hainan Island notified by the National Ministry of Agriculture, and their influences on native plants. We also focused on investigating the traits of six most widely spread invasive plants and plant distributions in seven types of terrestrial ecosystems. Three hypotheses were deployed in this study:(1) the ecological effects of plant invasion were related to the characteristics of invaded ecosystems and successional phases of invaded communities;(2) the invasive plants rather affected certain functional groups than the whole communities;(3) and most invasive plant species tended to colonize frequently disturbed ecosystems, while they were usually excluded by intact forest ecosystems. Methods The plot survey was conducted to investigate the distributions of the 20 target invasive plants. The appearance frequency of the six most widely spread invasive plants(i.e., Chromolaena odorata, Praxelis clematidea, Mimosa pudica, Wedelia trilobata, Conyza sumatrensis, and Lantana camara) was compared among seven terrestrial ecosystems(i.e., secondary forest, farmland, grassland, abandoned land, plantation, village, and forest edge) to evaluate the invasibility of different ecosystems. The plots invaded by target species were classified, and species richness of native species in these invaded plots was compared using one-way ANOVAS. Relationships between the total coverage of invasive plants and the species richness of native plants were assessed using a linear regression model. Important findings(1) A total of 11 noxious invasive plants were found in Hainan Island, accounting for 55% of the target specie.(2) The target invasive species were mostly distributed in the northeastern and southwesternregions of Hainan Island, less in the southeastern region, and least in the central region.(3) An order of the intensity regarding plant invasiveness was expressed as Praxelis clematidea Chromolaena odorata Mimosa pudica Wedelia trilobata Lantana camara Conyza sumatrensis. The appearance frequency of Conyza sumatrensis and Lantana camara showed no significant differences among the surveyed ecosystems, while Praxelis clematidea, Mimosa pudica and Wedelia trilobata had obviously higher appearance frequency in plantations and abandoned lands, in farmlands, and in plantations, respectively.(4) Farmlands, plantations and abandoned lands were the most frequently invaded ecosystems; but forest edges and natural secondary forests appeared to be less vulnerable to plant invasion.(5) The appearance frequency of invasive plants was negatively correlated with plant coverage of the community invaded by the target species. The total coverage of invasive plants and the richness of native plant species showed a positive correlation in grasslands when the coverage was within a certain extent, and a negative correlation both in forest edges and abandoned lands, and no obvious correlation in plantations farmlands and village sites.

Curvilinear effects of invasive plants on plant diversity: plant community invaded by Sphagneticola trilobata.

The effects of invasive plants on the species diversity of plant communities are controversial, showing either a positive or negative linear relationship. Based on community data collected from forty 5 m×5 m plots invaded by Sphagneticola trilobata in eight cities across Hainan Island, China, we found S. trilobata decreased plant community diversity once its cover was beyond 10%. We demonstrated that the effects of invasive/native plants on the plant diversity of communities invaded by S. trilobata were curvilinear. These effects, which showed peaks under different degrees of vegetation cover, appeared not only for S. trilobata and all invasive plants, but also for all native plants. Invasive plants primarily had negative effects on plant diversity when they became abundant at a much lower cover level (less than 35%), compared with the native plants (over 60%). Thus, it is necessary to distinguish a range for assessing the effects of plants, especially invasive plants. Our results also confirmed that the invasion intensity of invasive alien plants increased with the intensity of local economic development. We highlight and further discuss the critical importance of curvilinear effects of biological invasion to provide ideas regarding the conservation of local biodiversity and the management of invasive plants.

Ecological consequences of plant clonality.

Clonal plants are those that reproduce asexually by means of vegetative offspring that remain attached to the parent, at least until they establish. Clonal plant species are widespread, dominate a variety of habitats and probably play key roles in the maintenance of biodiversity, ecosystem function and biological invasion. For example, many of the most invasive introduced plants in the world are clonal. This makes it important to deepen our understanding of the ecology of clonal plants, including effects of clonality on ecosystem function, species abundance, plant performance in different habitats, capacity for evolution and invasiveness. The six papers in this Highlight explore these effects. The effects of clonality on ecosystem function have been under-studied. In a conceptual review, Cornelissen et al. (2014) discuss likely potential effects based on a response – effect trait framework, and call for research that links clonal traits to traits that affect carbon, nutrient and water cycling. In order to promote understanding of how clonality shapes species abundance, Herben et al. (2014) examine the relationships between plant traits and species abundance in 836 perennial, herbaceous species in Central Europe. Their results show that clonal growth traits explain a substantial proportion of variation in abundance, and that capacity for clonal growth and lateral expansion are positively correlated with abundance at both regional and local scales. Patterns of resource sharing between connected ramets vary between and within clonal species and may reflect selection for performance in different habitats. Using a spatially explicit, dynamic model, Oborny and Hubai (2014) test how the proportion of resource-rich patches in a heterogeneous environment determine the relative foraging efficiencies of clones in which parental ramets do or do not subsidize the growth of offspring in resource-poor patches. Not sharing is more efficient than sharing when more than half of patches are rich, but a mixed strategy is most efficient over a wide range of environments. While clonal integration is well known to increase growth in patchy habitats, the underlying physiological mechanisms remain elusive. Roiloa et al. (2014) test the effects of integration on photochemical efficiency, leaf spectral reflectance, photosynthesis and discrimination between isotopes of carbon and nitrogen in the wild strawberry Fragaria vesca. Their results provide novel evidence that clonal plants may preferentially transport specific forms of nitrogen between connected ramets. Potential for the evolution and local adaptation of clonal plant species might be limited if reproduction is mainly asexual. James and McDougall (2014) use microsatellite analysis and chromosome counts to document genetic diversity in all known populations of the clonal shrub Grevillea renwickiana. They find that triploidy has probably rendered the species exclusively asexual, but somatic mutation has generated diversity within clones. Introduced, invasive, clonal plants often spread both via seed dispersal and vegetative growth. Qi et al. (2014) document inhibition of seedling establishment under existing clones in the clonal, invasive plant Wedelia trilobata. Removal of adult plants fosters seedling establishment: important information for controlling the spread of this species. These six papers illuminate different aspects of the ecology of clonal plants and tackle current questions about the ecological consequences of clonality. We hope that this Highlight will stimulate further ecological research on clonal plants.

Evolucion geomorfologica y vegetacion costera de playa Palmeras, Parque Nacional Natural Isla Gorgona, Pacifico Colombiano

A study of the geomorphology and vegetation in Palmeras Beach was conducted from a digital elevation model, systematic measurements of beach profiles for 15 months, analysis of equilibrium shape and measurements of vegetation, electric conductivity of the floodwater and granulometry at 15 parcels established along the beach. The beach can be divided into two sectors. The NE is characterized by a concave shape, beach cusps, steeper slope, higher elevation, wider dry zone, greater variability of the shape in plan and profile, greater tendency for accretion and herbaceous vegetation dominated by Rhynchospora polystachys. The SW sector has a convex shape, lower elevation, minimal dry zone width, lower variability of the plan and profile, its shape tends to erosion. The herbaceous vegetation is dominated by Sphagneticola trilobata and it has a higher proportion of dead palms. Although the length of the observations limits the conclusions on the seasonal and interannual variability of the beach, in the wet season there is loss of sand and the sea level rises. Also during El Nino years increased wave energy, which could be associated with coastal erosion was evident. In the long term, there is evidence of a change in wave direction and a tilting of the beach with accretion to the NE and erosion to the SW.

Light limitation and litter of an invasive clonal plant, Wedelia trilobata, inhibit its seedling recruitment.

Invasive clonal plants have two reproduction patterns, namely sexual and vegetative propagation. However, seedling recruitment of invasive clonal plants can decline as the invasion process proceeds. For example, although the invasive clonal Wedelia trilobata (Asteraceae) produces numerous seeds, few seedlings emerge under its dense population canopy in the field. In this study it is hypothesized that light limitation and the presence of a thick layer of its own litter may be the primary factors causing the failure of seedling recruitment for this invasive weed in the field. A field survey was conducted to determine the allocation of resources to sexual reproduction and seedling recruitment in W. trilobata. Seed germination was also determined in the field. Effects of light and W. trilobata leaf extracts on seed germination and seedling growth were tested in the laboratory. Wedelia trilobata blooms profusely and produces copious viable seeds in the field. However, seedlings of W. trilobata were not detected under mother ramets and few emerged seedlings were found in the bare ground near to populations. In laboratory experiments, low light significantly inhibited seed germination. Leaf extracts also decreased seed germination and inhibited seedling growth, and significant interactions were found between low light and leaf extracts on seed germination. However, seeds were found to germinate in an invaded field after removal of the W. trilobata plant canopy. The results indicate that lack of light and the presence of its own litter might be two major factors responsible for the low numbers of W. trilobata seedlings found in the field. New populations will establish from seeds once the limiting factors are eliminated, and seeds can be the agents of long-distance dispersal; therefore, prevention of seed production remains an important component in controlling the spread of this invasive clonal plant.

Patterns of Alien Plant Invasion across Coastal Bay Areas in Southern China

ABSTRACT Ren, H.; Guo, Q.; Liu, H.; Li, J.; Zhang, Q.; Xu, H., and Xu, F., 2014. Patterns of alien plant invasion across coastal bay areas in southern China. An understanding of the ways in which levels of invasions by alien species are correlated with environmental factors is helpful to manage the negative impacts of these invasive species. Two tropical coastal areas in South China, Shenzhen Bay and Leizhou Bay, are national nature reserves, but they are threatened by invasive plants. Here, we investigated the level of invasion by exotic plants at both bays, and its relationship with selected environmental factors. We found a total of 34 invasive plant species, 18 of which were present at both bays; among these, 15 species were in terrestrial areas, three were at the ecotone, and one was in the mangroves. The two bays had a similar degree of invasion but were dominated by different species. Three invasive species (Ipomoea purpurea, Wedelia trilobata, and Panicum repens) were abundant at both bays, and on...

Ethnomedicine of menstruation in rural Dominica, West Indies

Ethnopharmacological relevanceIn Dominica, women offer dysmenorrhea, delayed menses, and menorrhagia as prevalent menstrual troubles. Dominican humoral theory considers menstruation to be “hot” such that menstrual problems are caused by the introduction of too much “cold” in the body. These conditions can be painful and may require herbal medicine. Our method finds the most culturally salient plants for these conditions—those which are of common knowledge across the population. We hypothesize that cultural agreement on ethnobotanical treatments (1) reflects their perceived ethnophysiological efficacy, and that (2) salient plants contain bioactive compounds appropriate for the menstrual conditions for which Dominicans employ the plants. Materials and MethodsQualitative data on local explanatory models and treatment of menstrual conditions were collected using participant-observation, focus groups, and informal key informant interviews. Quantitative ethnobotanical data come from freelist (or “free-list”) tasks, conducted with 54 adults. ResultsMean salience values calculated from freelisted data reveal that the same four plants, Cinnamomum verum (synonym Cinnamomum zeylanicum) (Lauraceae), Mentha suaveolens (Lamiaceae), Pimenta racemosa (Myrtaceae) and Sphagneticola trilobata (synonym Wedelia trilobata) (Asteraceae) are used to treat dysmenorrhea and delayed menses. The only remedy reported for menorrhagia, Sphagneticola trilobata (Asteraceae), is also a treatment for dysmenorrhea and delayed menses. The Dominican humoral system views menstruation as a "hot" condition, yet these "bush medicines" are also "hot." Dominicans do not view menstruation as a problem, rather, they reckon that excess "cold" in a woman׳s menstruating body impedes menstrual function to cause problems thus requiring "hot" plants to alleviate their symptoms. A literature review revealed that all four plants contain analgesic, anti-nociceptive, and anti-inflammatory properties. Additionally, Mentha suaveolens is muscle-relaxing and anti-spasmodic, Cinnamomum verum has a mild anti-coagulant, and Sphagneticola trilobata has wound healing, anti-stress, and sedative properties. ConclusionsIn Dominican menstrual problems there is correspondence between cultural consensus, bioactivity, and humoral theory. Examining the ethnophysiology of menstruation and its complications provides evidence for the expectations of actions and effectiveness of locally culturally salient medicinal plants.

Local adaptation and phenotypic plasticity both occurred in Wedelia trilobata invasion across a tropical island

The role of the local adaptation and phenotypic plasticity of invasive species in their invasion of new environments has historically been a debatable issue, particularly at small spatial scales (e.g., different habitats within an island). We selected seven field sites across Hainan Island, Hainan Province, China, to investigate the role of local adaptation and/or phenotypic plasticity in the successful invasion of Wedelia trilobata by a field survey, molecular marker analysis, and common garden experiment. In the field survey, the clonal growth characteristics of W. trilobata showed significant differences among the seven sites, suggesting that the species was able to adapt to different environments. The mean phenotypic plasticity index of W. trilobata was higher than that of other invasive plant species (0.61 vs 0.48). The analysis of the inter-simple sequence repeat molecular markers of 420 individuals from the seven sites revealed a Shannon’s index that was similar to those of other invasive plants (0.29 vs 0.25). The nested analysis of the molecular variance in the genetic diversity of the population showed significant differences among the sites. In the common garden experiment, the growth characteristics of plants grown from the seven sites were significantly affected by light and density treatments but not by soil moisture. However, the responses of plants grown from different sites to light treatment varied. Plants from sunny sites had greater clonal traits than those from shady sites, indicating that local adaptation occurred in plant populations grown at some sites. Overall, our results implied that both phenotypic plasticity and local adaptation contributed to the successful invasion of W. trilobata across Hainan Island.

A hybrid of the invasive plant Sphagneticola trilobata has similar competitive ability but different response to nitrogen deposition compared to parent

AbstractHybridization between introduced and related native species has been suggested to be a key driving force of evolutionary processes in invasions that may be accelerated by increasing nitrogen (N) deposition. We carried out two experiments to compare the competitive ability of a newly‐reported putative hybrid (Sphagneticola calendulacea × Sphagneticola trilobata) to that of its invasive paternal parent and investigate its response to different N additions. Growth of the hybrid increased by 39.62 ± 15.69 % when grown with the native parent but showed no significant changes when grown with the invasive parent. Growth of invasive S. trilobata showed no significant changes when grown with the other two taxa. The hybrid and invasive parent inhibited the growth of the native parent by 33.27 ± 15.26 % and 78.56 ± 3.13 %, respectively. Low level N addition (50 kg N ha−1) enhanced the growth of both the hybrid and native parent, whereas medium and high levels of N additions (150, 300 kg N ha−1) had no effects on hybrid growth but decreased native parent growth. However, all N treatments had no significant effects on the growth of the invasive parent. Our results suggest that the hybrid is an equal competitor to its invasive parent and is more susceptible to N deposition. Therefore, this hybrid could be a threat to native diversity but may decline more than the invasive parent under high N conditions.

Growth and Yield of Chili Pepper as Affected by Weed Based Organic Compost and Nitrogen Fertilizer

Fertility improvement of Ultisol is inevitable to increase growth and yield of chili pepper since the nutrient availability and organic matter of this soil is relatively low. Application of organic fertilizer will enhance microorganism activity in soil, thereafter will improve the availability of nutrients as well as other chemical, physical, biological properties of the soil. Most of manure releases nutrient quite slowly; therefore, addition of nitrogen to soil is expected to speed up the availability of nutrient to plant. Weed based organic fertilizers from Wedelia (Wedelia trilobata) and Siam weed (Chromolaena odorata) biomass have potential to substitute inorganic fertilizer. The objective of the experiment was to compare the effects of weed based organic compost and dry leaves compost with or without addition of nitrogen fertilizer on growth and yield of chili pepper. The experiment was carried out using Completely Randomized Design (CRD) with treatments of 200 kg urea ha-1; Wedelia compost (WDC) 20 ton ha-1; WDC 15, 10, and 5 ton ha-1 with addition of 200 kg urea ha-1 respectively; Siam weed compost (SWC) 20 ton ha-1, SWC 15, 10, and 5 ton ha-1 with addition of 200 kg urea ha-1 respectively; and dry leaves compost (DLC) 20 ton ha-1, DLC 15, 10, and 5 ton ha-1 with addition of 200 kg urea ha-1 respectively. The result revealed that composts with or without addition of nitrogen fertilizer had similar responses on the growth of chili pepper. Wedelia and Siam weeds compost at 20 ton ha-1 tended to give better yield of chili pepper as compared to application of urea alone. This result indicated that weed based organic fertilizers could substitute nitrogen fertilizer.

Growth and Yield of Chili Pepper under Different Time Application of Wedelia (Wedelia trilobata) and Siam Weed (Chromolaena odorata) Organic Fertilizers

Low content of soil organic matter and low availability of nutrients in Ultisol are major constraints of this soil to support growth and development of chili pepper. Application of organic fertilizer is required to increase content of soil organic matter as well as to improve other chemical, biological, physical properties of this soil. Wedelia ( Wedelia trilobata ) and Siam Weed ( Chromolaena odorata ) are potential sources of organic fertilizer. The aim of this study was to compare growth and yield of chili pepper under different time application of Wedelia and Siam Weed based organic fertilizer s . Greenhouse house experiment was conducted employing Completely Randomized Design with 2 factors namely Wedelia and Siam Weed composts as first factor and 5 (five) different time of application as second factor. Each treatment was replicated 5 times. The study showed that most variables observed in this experiment were not affected by types of compost. Only were plant height, canopy width and dry weight of biomass significant difference between the two composts. Siam weed compost applied two weeks before planting resulted in plant canopy wider than Wedelia compost. However, Wedelia compost applied at planting resulted in longer chili pepper as compared to Siam weed compost. The experiment also revealed that Wedelia compost produced higher plant height and root dry weight as compared to Siam weed compost.

Different degrees of plant invasion significantly affect the richness of the soil fungal community.

Several studies have shown that soil microorganisms play a key role in the success of plant invasion. Thus, ecologists have become increasingly interested in understanding the ecological effects of biological invasion on soil microbial communities given continuing increase in the effects of invasive plants on native ecosystems. This paper aims to provide a relatively complete depiction of the characteristics of soil microbial communities under different degrees of plant invasion. Rhizospheric soils of the notorious invasive plant Wedelia trilobata with different degrees of invasion (uninvaded, low-degree, and high-degree using its coverage in the invaded ecosystems) were collected from five discrete areas in Hainan Province, P. R. China. Soil physicochemical properties and community structure of soil microorganisms were assessed. Low degrees of W. trilobata invasion significantly increased soil pH values whereas high degrees of invasion did not significantly affected soil pH values. Moreover, the degree of W. trilobata invasion exerted significant effects on soil Ca concentration but did not significantly change other indices of soil physicochemical properties. Low and high degrees of W. trilobata invasion increased the richness of the soil fungal community but did not pose obvious effects on the soil bacterial community. W. trilobata invasion also exerted obvious effects on the community structure of soil microorganisms that take part in soil nitrogen cycling. These changes in soil physicochemical properties and community structure of soil microbial communities mediated by different degrees of W. trilobata invasion may present significant functions in further facilitating the invasion process.

Assessment of Allelopathic Potential of &lt;i&gt;Wedelia trilobata&lt;/i&gt; on the Germination, Seedling Growth and Chlorophyll Content of Rape

Wedelia trilobata(L.) Hitche is a widespread alien invasive weed in south China and has been reported to show allelopathic potential causing biological suppression on some plants. In this study, the allelopathic effects of aqueous extracts from the leaves ofW. trilobatawere tested on the seed germination, shoot growth and total chlorophyll content of rape (Brassica campestrisL.) using Petri dish bioassay. The results showed that the aqueous extracts at the concentration from 25% to 100% caused a significant reduction in the germination percentage, shoot length and total chlorophyll content of rape. This inhibitory effect was concentration-dependent. These results suggested there was a strong potential phytotoxic effect ofW. trilobataon rape andthis effect might reduce the production of some crop species.

Essential oil composition of Sphagneticola trilobata (L.) Pruski from India

This study aimed to explore the potential of an invasive alien species, Sphagneticola trilobata (L.) Pruski, that grows in foothill region of northern India. The volatile oil from the aerial parts of S. trilobata was isolated by hydrodistillation method and analysed using capillary gas chromatography–flame ionization detector (GC–FID) and GC–mass spectrometry (GC–MS) during different seasons. Volatile oil yield varied from 0.18 to 0.25% in different seasons, with the maximum in winter season. Altogether, 43 constituents, representing 96.1–97.3% of the total oil composition were identified. Major constituents of the oils were α-pinene (78.6–83.3%), α-phellandrene (1.3–4.1%), sabinene (1.4–1.9%), limonene (1.2–1.9%), β-pinene (1.0–1.6%), camphene (0.7–2.0%), 10-nor-calamenen-10-one (<0.05–1.5%), germacrene D (0.1–1.4%) and γ-amorphene (<0.05–1.3%). The comparative results showed no big differences in the oil composition of this plant due to season of collection. It is concluded that the S. trilobata population grown in this region could be utilized as a potential source of industrial molecule, α-pinene.

Impact of Sphagneticola trilobata on Plant Diversity in Soils in South-East Viti Levu, Fiji

Impact of Sphagneticola trilobata on Plant Diversity in Soils in South-East Viti Levu, Fiji

Eudesmanolides from Wedelia trilobata (L.) Hitchc. as Potential Inducers of Plant Systemic Acquired Resistance

Ten eudesmanolides (1-10) including five new ones (1-4 and 6) were isolated from the whole plant of Wedelia trilobata (L.) Hitchc., a notoriously invasive weed in South China. As main constituents of W. trilobata, eight of these eudesmanolides were tested for their antitobacco mosaic virus (TMV) activities by the conventional half-leaf and leaf-disk method along with Western blot analysis. All of the tested compounds, at 10 μg/mL, showed strong antiviral activities in the pretreated tobacco plants with inhibition rates ranging from 46.7% to 76.5%, significantly higher than that of the positive control, ningnanmycin (13.5%). Their potential of inducing systemic acquired resistance (SAR) was also evaluated, and compounds 1 and 8 showed excellent induction activities. Furthermore, it was found that different concentrations of compound 1 promoted phenylalanine ammonia-lyase (PAL) activity in tobacco plants. To our knowledge, this is the first report that eudesmanolides could induce resistance in tobacco plants against the viral pathogen TMV.

Efeito de extratos aquosos de espécies de Asteraceae sobre Meloidogyne incognita

Estudou-se, in vitro e in vivo a atividade nematicida dos extratos aquosos de vedélia (Sphagneticola trilobata), erva-de-touro (Tridax procumbens), cravo-de-defunto (Tagetes patula), girassol mexicano (Tithonia diversifolia), botão de ouro (Unxia suffruticosa) e zínia (Zinnia peruviana), sobre Meloidogyne incognita. Os extratos foram preparados na proporção de 1,0g do material seco e triturado para 10mL de água destilada e armazenados por 24h, sendo seguidamente utilizados nos experimentos. Nos testes in vitro, foram depositados 4,0mL do extrato bruto e 2,0mL de uma suspensão aquosa contendo 200 ovos do nematóide em placas de Petri de 5cm de diâmetro e, quinze dias após, procedeu-se a contagem do número de juvenis eclodidos e dos ovos remanescentes para o cálculo das porcentagens de eclosão. Nos testes in vivo, os extratos foram aplicados, separadamente, via pulverização foliar, tratamento de raiz e vertido no solo, semanalmente durante 60 dias. Como testemunha utilizou-se apenas água nos dois experimentos. No ensaio in vitro observou-se que todos os extratos foram eficientes na redução da eclosão de juvenis de M. incognita quando comparados à testemunha, as porcentagens de redução foram 89,96%, 91,13%, 92,48%, 92,72%, 93,2% e 97,48% para erva-de-touro, cravo-de-defunto, girassol mexicano, vedélia, botão de ouro e zínia, respectivamente, e no ensaio in vivo, que os tratamentos não exerceram nenhum efeito sobre o peso do sistema radicular dos tomateiros, no entanto, observou-se que os resultados diferiram entre as espécies utilizadas e a forma de aplicação do extrato na avaliação do peso fresco da parte aérea das plantas. Quanto ao fator de reprodução, observou-se que nenhum dos extratos apresentou diferença estatística em relação à testemunha, no entanto, quando se compara as diferentes formas de aplicação dos mesmos, observa-se que houve diferença estatística quando os extratos de erva de touro e girassol mexicano foram aplicados via pulverização foliar e no tratamento de raiz, contudo, não houve diferença quando estes extratos foram aplicados em forma de rega no solo.

Three species of native Thai honey bees exploit overlapping pollen resources: identification of bee flora from pollen loads and midguts from Apis cerana, A. dorsata and A. florea

SummaryIn this study, we investigated the bee flora utilised by the Thai honey bees, Apis cerana, A. dorsata and A. florea in Nan province, northern Thailand, through the identification of pollen grains from their pollen loads and midguts. We compared the pollen grains morphologically to match with local flowering plants and determined their protein concentration using a Bradford assay. The results showed that 8 families and 15 species were found by pollen load analysis whilst 12 families and 25 species were found from pollen grains of the bee midguts. The greatest number of bee flora was found from pollen loads of A. cerana, (11 species), while there were fewer for A. florea (10 species) and the fewest with A. dorsata (6 species). The highest number of bee flora species identified from pollen was found in the midgut of A. cerana, with 19 species, while A. florea had 13 and A. dorsata with only 11. The results show that the major pollen source plants of the three native honey bee species of Thailand were Mimosa pudica L., M. pigra, Celosia argentea L., Zea mays L., Wedelia trilobata L. and Syzygium malaccense L. The protein content ranged from 31.85 ± 0.83 to 48.44 ± 0.81 mg/100 mg pollen. The most abundant pollen source was from M. pudica L., perhaps because of the flower structure, shape, size, long blooming season, wide distribution, high protein concentration (43.31 ± 0.79 mg/100 mg pollen) or a combination of these characteristics.