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Uptake of host plant alkaloids by root parasitic Pedicularis ssp
Abstract
Five species of Pedicularis were examined for evidence of alkaloid transfer from host plants. Pedicularis groenlandica and P. bracteosa were found to take up the pyrrolizidine alkaloid senecionine from the host Senecio triangularis. Pedicularis crenulata contained anagyrine from its host Thermopsis montana and P. grayi contained N-methylcytisine from its Thermopsis divaricarpa host. Pedicularis racemosa contained quinolizidines from a Lupinus argenteus hybrid. In addition, P. bracteosa was found to contain pinidinol, taken up from the host Picea engelmannii.
... Studies have also reported a 40% reduction in mycorrhizal richness in tree hosts during mistletoe infestation [133,134]. In terms of foliar appearance, mistletoes often mimic their hosts [135][136][137]. This prevents them from being recognized by predators and herbivores that feed on them [135][136][137][138][139]. The exploitation of secondary metabolites from the host is known to confer such properties [135][136][137]140]. ...
... In terms of foliar appearance, mistletoes often mimic their hosts [135][136][137]. This prevents them from being recognized by predators and herbivores that feed on them [135][136][137][138][139]. The exploitation of secondary metabolites from the host is known to confer such properties [135][136][137]140]. ...
... In terms of foliar appearance, mistletoes often mimic their hosts [135][136][137]. This prevents them from being recognized by predators and herbivores that feed on them [135][136][137][138][139]. The exploitation of secondary metabolites from the host is known to confer such properties [135][136][137]140]. By doing so, mistletoe bypasses natural removal from hosts and escapes pruning or pollarding practices. ...
Mistletoes have been considered a keystone resource for biodiversity, as well as a remarkable source of medicinal attributes that attract pharmacologists. Due to their hemiparasitic nature, mistletoes leach water and nutrients, including primary and secondary metabolites, through the vascular systems of their plant hosts, primarily trees. As a result of intense mistletoe infection, the hosts suffer various growth and physiological detriments, which often lead to tree mortality. Because of their easy dispersal and widespread tropism, mistletoes have become serious pests for commercial fruit and timber plantations. A variety of physical and chemical treatment methods,
along with silvicultural practices, have shaped conventional mistletoe management. Others, however, have either failed to circumvent the growing range and tropism of these parasitic plants or present significant environmental and public health risks. A biocontrol approach that could sidestep these issues has never achieved full proof of concept in real-field applications. Our review discusses the downsides of conventional mistletoe control techniques and explores the possibilities of biotechnological approaches using biocontrol agents and transgenic technologies. It is possible that smart management options will pave the way for technologically advanced solutions to mitigate mistletoes that are yet to be exploited.
... The very first Pinus piperidine extracted from foothill pine was alphapipecoline & cis-pinidine [9] followed by the detection of epidihydropinidine & cis-pinidinol from Engelmann spruce. Surveys conducted in different species of Pinus and related genus like Picea have revealed the presence of unstable piperidine metabolites [10][11][12][13]. Piperidine alkaloids have also been found in Abies, another member of Pinaceae; however, they are not available in large quantities as Pinus and Picea [14]. ...
... A subalpine woodland pinidione was earlier obtained from the Mealybug ladybird [17]. Although alkaloids found in bracted lousewort are extracted from the plant hosts, it is believed that beetles synthesize de novo piperidine alkaloids, indicating converged evolution [11,13,17]. Similarly, members of Pinaceae such as Pinus and Picea also reveal many distinct properties in their alkaloid composition. ...
... The pinidine's composition and complete structure are calculated as 2R-methyl 6R-(2E-propenyl)piperidine [21,22]. However, several other alkaloids of piperidine have been identified from species of Pinus and another related genus like Picea (Schneider and Stermitz, 1990) [11]. In particular, both cis-and trans-piperidine alkaloids are present in sprucing plants, while pines appear to produce mostly cis-piperidine alkaloids [10]. ...
Background
Pinus and other related conifers belonging to family pinaceae are most commonly used medicinal plants in Indian North-western Himalayas. Various parts of these plants including needles are source of several well known alkaloids. Of all the alkaloids, piperidine group is one of important component and hold considerable medicinal importance.
Methods
The group of alkaloids was initially identified from genus Piper through which a large variety of piperidine molecules have been extracted. The planar structure of this heterocyclic nucleus enables acetamide groups to be added at various ring configurations.
Results
In the area of drug research, the piperidine heterocycle has gained considerable interest. To produce a new therapeutic profile, the broad range of its therapeutic application paved the way for researchers to implant the nucleus from time to time in diversified pharmacophores.
Discussion
However, biological functions of piperidine metabolites have been mostly examined on a limited scale and that most of the findings are thus preliminary. We have tried to present different clinical applications of piperidine alkaloids in this study that researchers have already attempted to demystify from time to time.
Conclusion
Given the importance of the piperidine nucleus, the study will enable the researcher to produce scaffolds of the highest therapeutic efficacy. We have also illustrated different types of piperidine, its sources in different member of family pinaceae with special emphasis on Pinus.
... [27,28] P. comosa L. (a.n.) aerial parts verbascoside, forsythoside B [15] P. condensata aerial parts verbascoside, echinacoside, aucubin, 6-O-acetyl-aucubin, 8-epi-loganin, mussaenoside, shanzhiside methyl ester, gardoside methyl ester [29] P. crenulata Benth. (a.n.) aerial parts anagyrine, aucubin, euphroside, plantarenaloside [22,30] P. decora Franch. (a.n.) whole plant β-sitosterol, β-daucosterol, iso-verbascoside, kaempferol, aucubin, lamalbid, pedicularislactone glucoside, ningpogoside B, D-mannitol, β-(3′,4′-dihydroxyphenyl-O-a-L-rhamnopyranosyl-(1-3)-β-D-glucopyranoside, salicylic acid, 2,5-dihydroxybenzoic acid, 3-hydroxy-4-methoxybenzoic acid, 3-methoxy-4-hydroxybenzoic acid, aspartic acid, threonine, serine, glutamic acid, glycine, alanine, cysteine, methionine, isoleucine, phenylalanine, valine, arginine, proline, leucine, tyrosine P. wilhelmsiana aerial parts phenolics (exact compounds not specified) [12] As Table 1 clearly shows, only 59 species have been studied for their phytochemical profiles, and, out of these, 12 have been studied only preliminarily, evidencing the presence of some classes of natural compounds but not the specific compounds. ...
... tubiformis [58,59] pedicutricone A P. densispica P. tricolor [38,85] Terpenoids 1,2,3,16,19,20-hexahydroxyole an-12-en-28-oic acid P. kansuensis [50] 3β,19α-dihydroxy-12-ursen-28 -oic acid P. tricolor [85] β-sitosterol P. decora P. kansuensis P. tricolor [32][33][34][35][36]45,85] β-daucosterol P. decora P. kansuensis P. longiflora var. tubiformis P. muscicola P. tricolor [32][33][34][35][36]45,58,59,62,85] ecdysterone 3-O-β-D-galactoside P. striata [78] kidjolanin P. cephalantha [25] Alkaloids α-iso-lupanine P. semibarbata [72] anagyrine P. crenulata [30,42] indicaine P. dolichorrhiza P. dolichocymba [30,42] indicainine P. peduncularis [64] indicine P. peduncularis [64] lupanine P. racemosa [30] N-methyl-cytisine P. grayi P. peduncularis [30,64] peducularine P. peduncularis P. sarawschanica [64,71] pediculidine P. dolichocymba P. dolichorrhiza [30,42] pediculine P. dolichocymba P. dolichorrhiza [30,42] plantagonin P. peduncularis [64] plantagonine P. dolichocymba P. dolichorrhiza P. peduncularis P. sarawschanica [30,42,64,71] senecionine P. groenlandica [30] tetrahydrorhombifoline P. racemosa [30] Lignans and neo-lignans [54,83] (7S)-dehydro-diconiferyl alcohol-4-O-β-D-glucoside P. torta [84] (+)-isolariciresinol 3a-O-β-D-glucopyranoside P. densispica [39] alaschanioside A P. alaschanica P. artselaeri P. kansuensis P. resupinata [17,19,47,49,50] alaschanioside C P. alaschanica P. kansuensis P. resupinata [17,47,49,50] armaoside P. armata [18] citrusin A P. alaschanica P. artselaeri [17,19] citrusin B P. armata [17,18] ...
... tubiformis [58,59] pedicutricone A P. densispica P. tricolor [38,85] Terpenoids 1,2,3,16,19,20-hexahydroxyole an-12-en-28-oic acid P. kansuensis [50] 3β,19α-dihydroxy-12-ursen-28 -oic acid P. tricolor [85] β-sitosterol P. decora P. kansuensis P. tricolor [32][33][34][35][36]45,85] β-daucosterol P. decora P. kansuensis P. longiflora var. tubiformis P. muscicola P. tricolor [32][33][34][35][36]45,58,59,62,85] ecdysterone 3-O-β-D-galactoside P. striata [78] kidjolanin P. cephalantha [25] Alkaloids α-iso-lupanine P. semibarbata [72] anagyrine P. crenulata [30,42] indicaine P. dolichorrhiza P. dolichocymba [30,42] indicainine P. peduncularis [64] indicine P. peduncularis [64] lupanine P. racemosa [30] N-methyl-cytisine P. grayi P. peduncularis [30,64] peducularine P. peduncularis P. sarawschanica [64,71] pediculidine P. dolichocymba P. dolichorrhiza [30,42] pediculine P. dolichocymba P. dolichorrhiza [30,42] plantagonin P. peduncularis [64] plantagonine P. dolichocymba P. dolichorrhiza P. peduncularis P. sarawschanica [30,42,64,71] senecionine P. groenlandica [30] tetrahydrorhombifoline P. racemosa [30] Lignans and neo-lignans [54,83] (7S)-dehydro-diconiferyl alcohol-4-O-β-D-glucoside P. torta [84] (+)-isolariciresinol 3a-O-β-D-glucopyranoside P. densispica [39] alaschanioside A P. alaschanica P. artselaeri P. kansuensis P. resupinata [17,19,47,49,50] alaschanioside C P. alaschanica P. kansuensis P. resupinata [17,47,49,50] armaoside P. armata [18] citrusin A P. alaschanica P. artselaeri [17,19] citrusin B P. armata [17,18] ...
In this review, the relevance of the plant species belonging to the Pedicularis L. genus has been considered from different points of view. Particular emphasis was given to phytochemistry and ethnopharmacology, since several classes of natural compounds have been reported within this genus and many of its species are well known to be employed in the traditional medicines of many Asian countries. Some important conclusions on the chemotaxonomic and chemosystematic aspects of the genus have also been provided for the first time. Actually, this work represents the first total comprehensive review on this genus.
... This was followed by the identification of cis---pinidinol and epidihydropinidine from Picea engelmannii (Parry ex Engelm.), leading to a still growing number of compounds (Schneider & Stermitz, 1990;Schneider et al., 1991;Tawara et al., 1993Tawara et al., , 1999Todd et al., 1995). Surveys conducted with various Pinus and Picea species have shown that volatile piperidine alkaloids are not related to specific species but are commonly observed in the Pinaceae family (Stermitz et al., 1994;Gerson & Kelsey 2004). ...
... Identical compounds have also been found in insect and parasite species. For example, euphococcinine was originally isolated from a beetle (Euphorbia atoto), cis---pinidinol was first identified from root hemiparasite (Pedicularis bracteosa), and pinidinone was first isolated from the ladybird (Cryptolaemus montrouzieri) (Hart et al., 1967;Brown & Moore, 1982;Schneider & Stermitz, 1990). While alkaloids detected in Pedicularis bracteosa are taken up from the host plant, beetles are assumed to biosynthesize piperidine alkaloids de novo, suggesting converged evolution (Hart et al., 1967;Brown & Moore, 1982;Schneider & Stermitz, 1990;Tawara et al., 1993). ...
... For example, euphococcinine was originally isolated from a beetle (Euphorbia atoto), cis---pinidinol was first identified from root hemiparasite (Pedicularis bracteosa), and pinidinone was first isolated from the ladybird (Cryptolaemus montrouzieri) (Hart et al., 1967;Brown & Moore, 1982;Schneider & Stermitz, 1990). While alkaloids detected in Pedicularis bracteosa are taken up from the host plant, beetles are assumed to biosynthesize piperidine alkaloids de novo, suggesting converged evolution (Hart et al., 1967;Brown & Moore, 1982;Schneider & Stermitz, 1990;Tawara et al., 1993). ...
In this thesis, the aim is to clarify the appearance and the role of the poorly known piperidine alkaloids of Norway spruce (Picea abies L. Karsten). Piperidine alkaloids are minor secondary components for Pinaceae species and assumed to be part of its defensive chemistry. Various plants parts including buds, current and previous years needles, twigs and bark were investigated. Young seedlings, as well as young and mature trees were used as study material. The thesis included four experiments: the effect of regeneration method, the effect of climatic factors, the changes during shoot development and the effect of genetic background on alkaloid composition. To get more holistic picture, also some phenolics were investigated. The main components of P. abies alkaloids in samples investigated during this study were epidihydropinidine, cis pinidinol and 2 methyl 6 propyl 1,6 piperideine, which were detected in relatively constant concentrations (0.03, 0.01 and 0.01% dw, respectively) regardless of plant age or the plant part studied. In addition, a wide range of other piperidines, including mainly intermediates of biosynthesis or the derivatives of main components were detected. The accumulation of piperidine alkaloids in vegetative shoots occurs simultaneously in twigs and needles and was found to be closely related to bud opening. In addition, both genetic and environmental factors affected total alkaloid concentrations. Based on the studies conducted as part of this doctoral thesis, temperature is by far the most important regulatory factor for piperidine alkaloid accumulation in P. abies. Although the constant concentration of the major components suggest its importance in tree defence, field voles showed no avoidance of, but rather a preference for high alkaloid containing seedlings, indicating that compounds might act also as elicitors. The concentration of total alkaloids showed negative correlation with the concentration of total low molecular weight phenolics, possible referring trade off in secondary chemistry biosynthesis. Piperidine alkaloid compounds with high potential activity and
wide occurrence in Finland could also provide added value for forestry in the search for new bioactive compounds.
... Parasitic plants can in turn gain antiherbivore properties by taking up secondary metabolites from their host (e.g. (Marko & Stermitz, 1997;Schneider & Stermitz, 1990;Stermitz et al., 1989). Thus, parasitic plants give rise to new ecological interactions that modify biological communities (Hartley et al., 2015;Pennings & Callaway, 1996;Press & Phoenix, 2005;Watson, 2002) and are thus recognized as keystone species (Watson, 2001;Watson & Herring, 2012 (Mellado & Zamora, 2014b;Zuber, 2004). ...
... can take up and store secondary chemical compounds from the host, similar to other hemiparasitehost systems (e.g. (Marko & Stermitz, 1997;Schneider & Stermitz, 1990;Stermitz et al., 1989) (Camarero et al., 2017;Kainulainen et al., 1992), and wildres (Cannac et al., 2009a;Lavoir et al., 2013) are factors that have been thoroughly covered in the literature. ...
In this thesis, a study is made of the different roles that the European mistletoe (Viscum album subsp. austriacum) can play simultaneously in a Mediterranean pine forest, and their ecological consequences generating multiple plant–plant and plant–animal interactions in their ecosystem. Due to their hemiparasitic nature, the mistletoe has been traditionally regarded as a host pathogen, causing detrimental effects on growth, morphology, and reproduction. However, recently other ecological interactions that mistletoe establishes in the forest ecosystem have been found to be noteworthy, not only with its host but also with the rest of the community where they live. Consequently, the presence of mistletoe in the forest canopy can cause direct and indirect effects in their ecosystem through trophic and non– trophic relationships, favoring the restructure of community composition. Therefore, this thesis has been split into three main parts examining the role of mistletoe: I) as a keystone resource for its associated arthropods (Chapters 1–3); II) as direct competitor with its host (Chapters 4–5); and III) as indirect competitor with host–feeding herbivores (Chapter 6) and facilitator for the herbaceous community (Chapter 7). From a holistic view, it is concluded that mistletoes are keystone species that trigger a series of interactions with important ecological consequences at the community level, causing direct and indirect effects at different trophic levels. This has profound implications for the dynamics of the forest ecosystem, restructuring the entire community, from nutrient dynamics and herbaceous community to primary and secondary consumers. Thus, by simultaneously providing new resources while acting as a competitor and facilitator, mistletoes become ecosystem engineers, building an additional level of heterogeneity to the forest canopy and amplifying biodiversity and complexity in their ecosystem.
... contains supplementary material, which is available to authorized users. and Stermitz 1997;Schneider and Stermitz 1990;Stermitz et al. 1989). Thus, parasitic plants give rise to new ecological interactions that modify biological communities (Hartley et al. 2015;Pennings and Callaway 1996;Press and Phoenix 2005;Watson 2002) and are thus recognized as keystone species (Watson 2001;Watson and Herring 2012). ...
... In this study, we hypothesized that 1) mistletoes, due to their fusion with host-xylem and continuous uptake of sap and fluids (Zuber 2004), can take up and store secondary chemical compounds from the host, similar to other hemiparasite-host systems (e.g. Marko and Stermitz 1997;Schneider and Stermitz 1990;Stermitz et al. 1989); and 2) mistletoe parasitism causes varying qualitative and/or quantitative changes in the host-pine chemical profile, depending on the parasite load. To test these hypotheses, we first investigated the chemical profile of mistletoe leaves and pineneedlesoncurrent-year(new)andprevious-year(old)cohorts. ...
Stress caused by parasitic plants, e.g. mistletoes, alters certain host-plant traits as a response. While several physical implications of the parasite-host relation have been well studied, shifts in the host chemical profile remain poorly understood. Here we compare the chemical profiles of mistletoe (Viscum album subsp. austriacum) leaves and host pine (Pinus nigra subsp. salzmannii) needles and we investigate chemical changes in host needles of trees with different parasite loads (control, low, medium, and high). Our results reveal that despite the intimate contact between mistletoe and host pine, their chemical profiles differed significantly, revealing extremely low concentrations of defense compounds (including a complete lack of terpenes) and high levels of N concentrations in mistletoe leaves. On the other hand, parasitized pines showed unique chemical responses depending on parasite loads. Overall, the content in monoterpenes increased with parasitism. Higher parasitized pines produced higher amounts of defense compounds (phenols and condensed tannins) than less parasitized trees, but amounts in samples of the same year did not significantly differ between parasitized and unparasitized pines. Highly parasitized pines accumulated less N than pines with other parasite loads. The strongest response was found in sesqui- and diterpenes, which were at lower levels in pines under medium and high parasitism. Chemical responses of pines to mistletoe parasitism resembled reactions to other kinds of stress. Low levels induced reactions resembling those against drought stress, while medium and high parasitism elicited responses comparable to those against burning and defoliation.
... Most previously documented instances of defensive secondary metabolite transfer into parasitic plants involve alkaloids (Trautner, 1952;Schneider and Stermitz, 1990;Bäumel et al., 1993;Marko and Stermitz, 1997;Stermitz, 1998;Adler et al., 2001;Lehtonen et al., 2005;Cabezas et al., 2009), although a handful of studies have also documented the transfer of cardenolides, phenolics, and iridoid glycosides (Boonsong and Wright, 1961;Srimathi and Sreenivasaya, 1963;Subraman and Nair, 1966;Stermitz et al., 1993;Rothe et al., 1999). It is likely that these compounds constitute only a small subset of transferrable defense metabolites, given the existence of more than 4,000 species of parasitic plants that collectively feed on a much larger number of host species (Heide-Jørgensen, 2008) via intimate physical connections to host phloem, xylem, and/or parenchyma tissues (Hibberd and Jeschke, 2001). ...
... Our results provide, to our knowledge, the first evidence that glucosinolates from cruciferous hosts transfer into parasitic plants ( Fig. 1) and show that their transfer can have consequences both for the growth of dodder (Fig. 2) and for the performance of herbivores that feed upon dodder (Figs. 3 and 4). A diverse array of host secondary metabolites transfer into parasitic plant tissues (Trautner, 1952;Boonsong and Wright, 1961;Srimathi and Sreenivasaya, 1963;Subraman and Nair, 1966;Schneider and Stermitz, 1990;Bäumel et al., 1993;Stermitz et al., 1993;Marko and Stermitz, 1997;Rothe et al., 1999;Cabezas et al., 2009), and our findings invite further investigations into the roles of other compounds in inhibiting parasite growth and defense and/or enhancing parasite resistance to herbivores. Previous authors have noted the possibility that secondary metabolites (specifically alkaloids) might prove toxic to the parasitic plants that acquire them from host plants (Bäumel et al., 1995). ...
Parasitic plants and insect herbivores both feed on plants to acquire nutrition and other resources. Some herbivores also obtain toxins from host plants and sequester them for protection against their enemies. While this defense mechanism is well-studied in insects, remarkably little research has explored analogous host-derived defenses in parasitic plants. Nevertheless, a few studies indicate that the resistance of parasitic plants to insect enemies can depend on the identity of the parasite’s host. For example, aphids feeding on the parasitic vine dodder (genus Cuscuta) generally perform well when dodder is grown on tomato, but poorly when it is grown on turnip or onion—two plants bearing anti-insect toxins that are accessible to dodder via phloem. However, cabbage aphids (Brevicoryne brassicae), brassica specialists that are well adapted to the glucosinolate defense compounds produced by these plants, performed optimally on turnip-hosted dodder. In light of these findings we hypothesize that glucosinolate toxins from infested turnips translocate into dodders and confer resistance to aphids. This talk will report initial results from chemical and biological tests of this hypothesis, including the key finding that glucosinolates move readily into dodders from their Brassicaceous host plants. Our methods include HPLC analysis of glucosinolates and caged-aphid performance assays. This work has significant implications for the ecology of parasitic plants and their insect herbivores, as well as for the management of some of the world’s most devastating agricultural weeds.
... At the same time, the unique root hemiparasitic characteristics of P. kansuensis result it in having obvious advantages in competition for nutrition, light, and water with grasses and legumes. Especially in those areas where the grassland is overgrazed and vegetation is seriously damaged, the invasion rate is rapid, making it difficult for other species to grow and develop [16]. Therefore, the effective control of P. kansuensis has become the major problem in the restoration of the Bayanbulak grassland. ...
In order to study the changes in invasive plant population characteristics under different nutrient addition treatments, this study used the native invasive species Pedicularis kansuensis, which is spreading in the Bayabulak alpine grassland, as the research object and conducted two consecutive years of field studies in which nutrients were added to plots. Changes in the P. kansuensis population’s invasive characteristics were monitored in 2020 and 2021 in four different nutrient-addition treatments, namely no-nutrients (control), low-nitrogen, high-nitrogen, and phosphorus treatments. The result showed that (1) nutrient addition had significant effects on P. kansuensis height and root/shoot ratio (p < 0.05); the time effect had significant effects on P. kansuensis height, coverage, abundance, aboveground biomass, and belowground biomass (p < 0.01), and the interaction between nutrient addition and time had a significant effect on P. kansuensis height (p < 0.01). (2) Nitrogen addition effectively inhibited the growth and the development of P. kansuensis, especially under high-nitrogen conditions in the second growing season, where the effect of height (2.50 cm), coverage (0.13%), richness (3 strains), aboveground biomass (0.21 g m−2), and belowground biomass (0.03 g m−2) was significant, with the P. kansuensis population almost disappearing by the end of the trial. (3) Phosphorus addition had no significant effect on the P. kansuensis population’s invasive characteristics. These results indicate that higher nitrogen addition could effectively slow the invasion of the P. kansuensis population, and the findings of this study could provide certain baseline data and scientific guidance for the effective control of the P. kansuensis invasion of the Bayabulak alpine grassland in the future as well as identify certain theoretical bases for the effect of nutrient addition on invasive plants overall.
... Plant hemiparasites are known to obtain a wide range of primary compounds such as carbon, water and ions as well as secondary compounds from their hosts (Schneider & Stermitz 1990, Boros et al. 1991, Stermitz & Pomeroy 1992, Press et al. 1999. Numerous hemiparasites do not synthesize or modify the secondary compounds taken up from their hosts (Simms 1992), thus the presence of certain secondary compounds varies within and among the populations of hemiparasitic plants, depending on the host association of individual parasites (Stermitz & Harris 1987). ...
... aerial parts anagyrine, aucubin, euphroside, plantarenaloside [22,30] P. decora Franch. (a.n.) whole plant β-sitosterol, β-daucosterol, iso-verbascoside, kaempferol, aucubin, lamalbid, pedicularislactone glucoside, ningpogoside B, Dmannitol, β-(3',4'-dihydroxyphenyl-O-a-Lrhamnopyranosyl-(1-3)-β-D-glucopyranoside, salicylic acid, 2,5-dihydroxybenzoic acid, 3hydroxy-4-methoxybenzoic acid, 3-methoxy-4hydroxybenzoic acid, aspartic acid, threonine, serine, glutamic acid, glycine, alanine, cysteine, methionine, isoleucine, phenylalanine, alanine, valine, arginine, proline, leucine, tyrosine [31][32][33][34][35][36] P. densispica Franch. ...
In this review, the relevance of plants belonging to the Pedicularis L. genus was explored from different points of view. Particular emphasys was given especially to the phytochemistry and the ethnopharmacology of the genus since several classes of natural compounds have been evidenced within it and several Pedicularis species are well known to be employed in the traditional medicine of many Asian countries. Nevertheless, some important conclusions on the chemotaxonomic and chemosystematic aspects of the genus were also provided for the first time. This work represents the first total comprehensive review on the genus Pedicularis.
... species as well as from Picea engelmannii Parry ex Engelm. (Pinaceae) [84]. The uptake of norditerpenoid alkaloids by Castilleja sulphurea Rydb. ...
The present review gives an overview about natural products from the holoparasitic genus Orobanche (Orobanchaceae). We cover both genuine natural products as well as compounds sequestered by Orobanche taxa from their host plants. However, the distinction between these two categories is not always easy. In cases where the respective authors had not indicated the opposite, all compounds detected in Orobanche taxa were regarded as genuine Orobanche natural products. From the about 200 species of Orobanche s.l. (i.e., including Phelipanche) known worldwide, only 26 species have so far been investigated phytochemically (22 Orobanche and four Phelipanche species), from 17 Orobanche and three Phelipanche species defined natural products (and not only natural product classes) have been reported. For two species of Orobanche and one of Phelipanche dedicated studies have been performed to analyze the phenomenon of natural product sequestration by parasitic plants from their host plants. In total, 70 presumably genuine natural products and 19 sequestered natural products have been described from Orobanche s.l.; these form the basis of 140 chemosystematic records (natural product reports per taxon). Bioactivities described for Orobanche s.l. extracts and natural products isolated from Orobanche species include in addition to antioxidative and anti-inflammatory effects, e.g., analgesic, antifungal and antibacterial activities, inhibition of amyloid β aggregation, memory enhancing effects as well as anti-hypertensive effects, inhibition of blood platelet aggregation, and diuretic effects. Moreover, muscle relaxant and anti-spasmodic effects as well as anti-photoaging effects have been described.
... In contrast, total amino acids were similar for hosts and parasites but varied by host genotype 308 ( Figure 5D; Table II Our results provide the first evidence that glucosinolates from cruciferous hosts transfer into 316 parasitic plants ( Figure 1) and show that their transfer can have consequences both for the 317 growth of dodder ( Figure 2) and for the performance of herbivores that feed upon dodder 318 (Figures 3, 4). A diverse array of host secondary metabolites transfer into parasitic plants tissues 319 (see e.g., Trautner, 1952;Boonsong and Wright, 1961;Srimathi and Sreenivasaya, 1963;320 Subraman and Nair, 1966;Schneider and Stermitz, 1990;Bäumel et al., 1993;Stermitz et al., 321 1993;Marko and Stermitz, 1997;Rothe et al., 1999;Cabezas et al., 2009), and our findings 322 invite further investigations into the roles of other compounds in inhibiting parasite growth and 323 defense and/or enhancing parasite resistance to herbivores. Previous authors have noted the 324 possibility that secondary metabolites (specifically alkaloids) might prove toxic to the parasitic 325 plants that acquire them from host plants (Bäumel et al., 1995). ...
Parasitic plants acquire diverse secondary metabolites from their hosts, including defense compounds that target insect herbivores. However, the ecological implications of this phenomenon, including potential enhancement of parasite defenses, remain largely unexplored. We studied the translocation of glucosinolates from brassicaceous host plants (Arabidopsis thaliana) into parasitic dodder vines (Convolvulaceae: Cuscuta gronovii) and its effects on the parasite itself and on dodder-aphid interactions. Aliphatic and indole glucosinolates reached concentrations in parasite tissues higher than those observed in corresponding host tissues. Dodder growth was enhanced on cyp79B2 cyp79B3 hosts (without indole glucosinolates) but inhibited on atr1D hosts (with elevated indole glucosinolates) relative to wildtype hosts, which responded to parasitism with localized elevation of indole and aliphatic glucosinolates. These findings implicate indole glucosinolates in defense against parasitic plants. Rates of settling and survival on dodder vines by pea aphids (Acyrthosiphon pisum) were significantly reduced when dodder parasitized glucosinolate-producing hosts (wildtype and atr1D) compared to glucosinolate-free '‑GLS' hosts (cyp79B2 cyp79B3 myb28 myb29). However, settling and survival of green peach aphids (Myzus persicae) was not affected. Myzus persicae population growth was actually reduced on dodder parasitizing -GLS hosts compared wildtype or atr1D hosts, even though stems of the former contain less glucosinolates and more amino acids. Strikingly, this effect was reversed when the aphids fed directly upon Arabidopsis, which indicates an interactive effect of parasite and host genotype on M. persicae that stems from host effects on dodder. Thus our findings indicate that glucosinolates may have both direct and indirect effects on dodder-feeding herbivores.
... The structure and absolute configuration of pinidine was determined as 2R-methyl-6R-(2E-propenyl)-piperidine [(−)-9, Figure 4.1] (Tallent and Hornig, 1956;Hill et al., 1965). Since then several other piperidine alkaloids have been isolated from Pinus and Picea species (Stermitz and Miller, 1990;Schneider and Stermitz, 1990;Schneider et al., 1991;Tawara et al., 1993Tawara et al., , 1995Stermitz et al., 1994;Todd et al., 1995;Gerson and Kelsey, 2002) In general spruce species contain both cis-and trans-piperidine alkaloids, while the pines seem to contain cis-piperidine alkaloids only (Tawara et al. 1993, Stermitz et al., 1994. Several of the alkaloids common for pine and spruce species have also been found in insects. ...
... hypocistis races could be mediating the interactions between nectar and yeasts. Parasitic plants obtain secondary compounds from their hosts that can be transferred to all tissues of the parasites, including nectar, and this uptake depends on the identity of the host (Schneider and Stermitz 1990, Marko and Stermitz 1997, Adler and Wink 2001. If secondary compounds of C . ...
Nectar‐dwelling yeasts are emerging as widely distributed organisms playing a potentially significant and barely unexplored ecological role in plant pollinator mutualisms. Previous efforts at understanding nectar–pollinator–yeast interactions have focused on bee‐pollinated plants, while the importance of nectarivorous ants as vectors for yeast dispersal remains unexplored so far. Here we assess the abundance and composition of the nectar fungal microbiota of the ant‐pollinated plant Cytinus hypocistis, study whether yeast transmission is coupled with ant visitation, and discern whether ant‐ transported yeasts promote changes in nectar characteristics. Our results show that a high percentage of flowers (77%) and plants (94%) contained yeasts, with yeast cell density in nectar reaching up to 6.2 × 104 cells mm−3, being the highest densities associated with the presence of the nectar‐specialist yeast Metschnikowia reukaufii. The establishment of fungal microbiota in nectar required flower visitation by ants, with 70% of yeast species transported by them being also detected in nectar. Ant‐vectored yeasts diminished the nutritional quality of nectar, with flowers exposed to pollinators and yeasts containing significantly lower nectar sugar concentration than virgin flowers (13.4% and 22.8%, respectively). Nectar of flowers that harbored M. reukaufii showed the lowest quality, with nectar concentration declining significantly with increasing yeast density. Additionally, yeasts modified patterns of interpopulation variation in nectar traits, homo genizing differences between populations in some nectar attributes. We show for the first time that the outcome of the tripartite pollinator–flower–yeast interaction is highly dependent on the identity and inherent properties of the participants, even to the extent of influencing the species composition of this ternary system, and can be mediated by ecological characteristics of plant populations. Through their influence on plant functional traits, yeasts have the potential to alter nectar consumption, pollinator foraging behavior and ultimately plant reproduction.
... Plant hemiparasites are known to obtain a wide range of primary compounds such as carbon, water and ions as well as secondary compounds from their hosts (Schneider & Stermitz 1990, Boros et al. 1991, Stermitz & Pomeroy 1992, Press et al. 1999. Numerous hemiparasites do not synthesize or modify the secondary compounds taken up from their hosts (Simms 1992), thus the presence of certain secondary compounds varies within and among the populations of hemiparasitic plants, depending on the host association of individual parasites (Stermitz & Harris 1987). ...
To test the hypothesis that higher antioxidant potential of hemiparasitic plants is due to sequestration of phenolic compounds from the host plants, samples of Dendrophthoe falcata, a hemiparasite collected from different hosts, were investigated for total phenolics, total flavonoids and 1,1-diphenyl-2-picryl-hydrazyl ( DPPH) radical scavenging activity. The hosts significantly influenced the phenolic content of the hemiparasite. However, similar influence was not detected on radical scavenging activity and no correlation was found in the phenolics and free radical scavenging activities. Further investigation on transfer of constituents revealed that D. falcata sample obtained from a host, Mangifera indica, contained mangiferin, a C-glucosyl xanthone, and some unidentified flavonoids as confirmed by HPTLC flavonoid patterns. The data indicated that the hosts significantly affected total phenolics and total flavonoids in a hemiparasite. This is the first report of transfer of mangiferin from M. indica to a hemiparasite. The present report points towards the need of further investigations on the possible role of transferred phenolics either as mediators of host defense, host defense compounds utilized as cues of identification of the host by the hemiparasite or compounds taken up by the parasites to support their defense against rejection by the hosts.
... Interactions between plant parasites and host species can have direct and indirect effects both on host and parasite performance, as well as their pollinators (Adler et al. 2001), and herbivores (Adler 2002(Adler , 2003Adler et al. 2001;Marko 1996;Marvier 1996). Parasitic plants can acquire secondary compounds from host species (Govier et al. 1967;Schneider and Stermitz 1990; Stermitz and Harris 1987), which in turn can alter species interactions. For example, acquisition of alkaloids from the host Lupinus albus directly reduced insect herbivory of Castilleja indivisa, and indirectly increased pollination (Adler et al. 2001). ...
Rare, parasitic plants pose an interesting challenge to restoration practitioners. In addition to the problems associated with small population size, rare parasites may also be limited by their host requirements. We examined how the performance of a rare Pacific Northwest hemiparasite, Castilleja levisecta, was affected by the availability of different host combinations in the greenhouse and in the field. Castilleja levisecta individuals were grown with two individuals of the grass Festuca roemeri, two individuals of the aster Eriophyllum lanatum, one individual of each of these species (a ''mixed'' treatment), or without any host. We did not find support for the complimentary diet hypothesis, which predicts that parasites grown with multiple host species perform better than individuals grown alone or with a single host. In the greenhouse, C. levisecta individuals grown in the mixed treatment had greater stem growth than those planted with F. roemeri, but did not differ from E. lanatum or no-host treatments. In the field, vole activity had indirect effects on C. levisecta survival mediated through host species: vole tunneling and C. levisecta mortality were strongly associated with host treatments including E. lanatum. Vole tunneling and C. levisecta mortality were strongly associated with host treatments including E. lanatum. Field survival of no-host and F. roemeri treatments were significantly higher than those grown with E. lanatum. Our results emphasize the importance of basing conservation decisions on experimental research conducted under conditions similar to those of the intended application, as greenhouse results were a poor predictor of field performance. For restoration of endangered hemiparasitic plants, we recommend planting with hosts that are not attractive to herbivores.
... rubricaulis). Numerous other examples of alkaloid uptake by hemiparasitic Orobanchaceae have been observed, for instance: between the hosts Senecio, Thermopsis, Lupinus and Pinus to Pedicularis species (Stermitz et al. 1989;Schneider & Stermitz 1990;Mead & Stermitz 1993); from Delphinium, Senecio, Lupinus and Liatris to Castillleja species (Stermitz & Harris 1987;Mead et al. 1992;Stermitz & Pomeroy 1992;Marko & Stermitz 1997); and from Lupinus to Orthocarpus (Boros et al. 1991). Further, Stermitz et al. (1993) observed iridoid glycoside transfer between a host and hemiparasite (Penstemon teucriodes and Castellija integra, respectively). ...
In addition to reducing the overall productivity of the host, hemiparasitic Orobanchaceae can alter host allometry and both higher and lower dry matter allocation to roots has been reported (e.g. Matthies 1995, 1997; Watling & Press 1997). However, the impacts on host roots go further and there is increasing evidence to show that parasitic angiosperms influence the mycorrhizal associations of host plants. Davies & Graves (1998), for example, observed that the percentage root length colonized in Lolium perenne by arbuscular mycorrhizal (AM) fungi was reduced by about 30% when parasitized by Rhinanthus minor (Lolium growth was also reduced by about 50%). This reduction in colonization may be explained if the mycorrhizal fungus is a weaker competitor for host carbon than the hemiparasite. Further, Rhinanthus growth and reproductive output was greater by 58% and 47%, respectively, when parasitizing mycorrhizal Lolium compared with non-mycorrhizal Lolium, indicating that the host's AM fungi may enhance availability of nutrients to the hemiparasite. Indeed, since the mycorrhizal stimulation of plant productivity was much greater for the hemiparasite than for the host, this indicates that any increase in nutrient supply was a direct effect of mycorrhizal uptake, rather than an indirect effect of mycorrhizal infection increasing host size (and therefore its nutrient source size to the hemiparasite). Hemiparasite–mycorrhiza interactions have also been reported by Salonen et al. (2000), where the hemiparasite Melampyrum had greater growth and produced more flowers when parasitizing Pinus sylvestris colonized by ecto-mycorrhizal (EM) fungi than when parasitizing non-mycorrhizal Pinus. EM symbiosis increased the growth of Pinus and thus greater resources could be made available to Melampyrum not just through nutrient uptake by the EM fungi, but also through greater photosynthetic leaf area of the larger mycorrhizal Pinus.
... We extend the three-way interactions of previous studies to include a four-way interaction among a host grass (Lolium pratense), its symbiotic endophytic fungus (Neotyphodium uncinatum), a root hemiparasitic plant (Rhinanthus serotinus) of the host grass, and a generalist herbivore (the aphid Aulacorthum solani) of the hemiparasite. First, we examine if alkaloids of endophytic origin are transferred from the shared host grass to the hemiparasitic plant, and thus, like plant-origin secondary compounds (Schneider & Stermitz 1990;Boros et al. 1991;Adler 2000Adler , 2002Adler & Wink 2001), change the quality of the parasitic plant for herbivores. Finding that alkaloids of endophyte origin were transferred from the shared host grass to the hemiparasitic plant, we hypothesized that the hemiparasite may gain protection from herbivores. ...
Plants growing in natural environments experience myriad interactions with a diverse assemblage of pathogens, parasites and mutualists. Many of these interactions involve symbiotic bacteria and fungi, but they also include macroparasitic plants. In this study, we investigated the interactions among a host grass (Lolium pratense, ex., Festuca pratensis), its symbiotic endophytic fungus (Neotyphodium uncinatum), a root hemiparasitic plant (Rhinanthus serotinus) of the host grass and a generalist herbivore (aphid Aulacorthum solani) of the hemiparasite. We demonstrate that the hemiparasitic plant acquires defending mycotoxins produced by the endophytic fungus living within their shared host grass. The uptake of defensive mycotoxins from the endophyte-infected host grass enhances the resistance of the hemiparasitic plant to the generalist aphid herbivore. Endophyte infection increases the performance of the hemiparasitic plant, but reduces the growth of the host grass. In other words, the mutualistic endophytic fungus becomes parasitic in the presence of the hemiparasitic plant. Our results suggest that the outcomes of grass–endophyte interactions are conditional on the complexity of community-level interactions; thus, the outcome of multispecies interactions may not be predictable from pair-wise combinations of species.
Parasitic plants are specialized plant functional group which obtains all or parts of their nutrition from another plant without contributing to the benefit of the host plant and sometimes causing extreme damage to the host. Occurrence of 18 species of such parasitic plants in Odisha is a wealthy acquaintance for us. In our usual field trips to forests, when we see the plant Dodder (Cuscuta spp.) growing parasitically on a host plant, a lot of query come to our mind about their morphology, nutrition, distribution and biology. This compile us for exploring parasitic plants in different parts of the state Odisha during the survey we came across. Till 2018, we came across several species of parasitic plants mostly found in terrestrial and epiphytic conditions. Although, some of the genera such as Orobanche, Cuscuta have negative impact towards cultivated crops, but they are largely useful in terms of medicinal, edible and commercial purposes. Almost all species under this group encompass ecological, economical, medicinal and environmental importance. We have used both primary and secondary sources of data for collecting plant specimens, photographs and other information about parasitic plants and tried our level best to provide concise information on such group of plants to the extent of possible. We are sure that this will create a better understanding among the readers. We hope this book will be of immense help to students, teachers, researchers, nature lovers and conservationists to improve their popular understanding on this special group of plants. There is a scope for improvement of this book in future and your suggestions are most welcome in this regard
Die Familie liefert zahlreiche Arznei- und Zierpflanzen (1). Ihre Abgrenzung gegen Globulariaceen, Bignoniaceen, Gesneriaceen, Myoporaceen und einige weitere Tubifloren-Taxa ist unscharf, was zur Folge hat, daß Gattungen wie Paulownia, Rehmannia und Triben, wie die Leucophylleae mit etwa 12 Arten in den Gattungen Eremogeton (nur E. grandiflorus), Taxonanthus (nur T. pringlei) und Leucophyllum (2) verschiedenen Familien eingereiht wurden und werden.
A number of alkaloids are derived from ornithine and lysine by decarboxylation, conversion by amine oxidases to the corresponding aldehyde, and cyclization to a 5-membered ring system (pyrrolidine alkaloids) and a 6-membered ring system (piperidine alkaloids). Several other alkaloids that coinciden-tally have similar structures have been discussed under the groups of alkaloids to which they are most closely related.
Effect of solvent composition on recovery of polyphenolics from Loranthaceae mistletoes and their antioxidant activities were examined in this work. All extracts contain higher amount of flavonoid content than proanthocyanidin content which is reflected by their higher antioxidant potential. On the basis of optimization of extraction method, the 70 % methanol extract of D. trigona contains higher amount of polyphenolics and flavonoids which shows IC 50 values of 7.82 μg/mL in DPPH and 8.7 μg/mL in nitric oxide scavenging activity. Thus, it can become an important natural source of antioxidant phenolics.
Alkaloids can be transferred from alkaloid-containing host plants to a variety of normally alkaloid-free parasitic plants. Sporadic and relatively incomplete reports of such alkaloid assimilation by parasitic plants appeared over the course of several decades before 1980. Access to these reports can be obtained from a review (Stermitz, 1990) and in typical papers of the 1980s (Wink et al., 1981; Czygan et al, 1988; Cordero et al., 1989). The focus of this review will be on the more detailed recent studies where some attempt has been made to put data into a broader biological or ecological context, rather than simply document occurrence of the phenomenon.
Alkaloids - Secrets of Life: Alkaloid Chemistry, Biological Significance, Applications and Ecological Role, Second Edition provides knowledge on structural typology, biosynthesis and metabolism in relation to recent research work on alkaloids, considering an organic chemistry approach to alkaloids using biological and ecological explanation. The book approaches several questions and unresearched areas that persist in this field of research. It provides a beneficial text for academics, professionals or anyone who is interested in the fascinating subject of alkaloids. Each chapter features an abstract. Appendices, a listing of alkaloids, and plants containing alkaloids are all included, as are basic protocols of alkaloid analysis.
Pyrrolizidine, quinolizidine, and indolizidine alkaloids are chemically diverse and restricted in distribution. Some similarities in structures and biosynthesis exist, but as the pathways become more clear, these three major groups of alkaloids definitely are of distinct origins. Pyrrolizidine alkaloids are derived from arginine or ornithine and possess two fused 5-membered rings that share a nitrogen atom. Quinolizidine alkaloids are derived from lysine and have two fused 6-membered rings that share a nitrogen atom. Indolizidine rings have a 5-membered ring fused to 6-membered ring and share a nitrogen atom. Pyrrolizidine, quinolizidine, and indolizidine alkaloids are involved in many plant-herbivore interactions, but are of anthropocentric importance chiefly because of their involvement in livestock poisoning, although several have antitumor activity and others are used medicinally. The phenanthroindolizidine alkaloids are a major subgroup of indolizidine alkaloids.
While the role of parasites in shaping population and community dynamics has been increasingly appreciated, researchers have largely ignored the ecology of parasitic plants. Parasitic plants obtain water, sugar, nitrogen compounds, and a variety of secondary metabolites from their host plants. In a greenhouse study, I examined the direct interactions of a parasitic plant, Castilleja wightii (Scrophulariaceae), with three plant hosts and the indirect effects of this parasitism on the performance of a parasite-feeding herbivore. The three host species, Lupinus arboreus, Artemisia pycnocephala, and Eriophyllum staechadifolium, directly and differentially affected C. wightii flower production, although parasite biomass was not affected by host species. Surprisingly, parasite performance was weakest when attacking a leguminous host, although parasite total nitrogen was highest when growing on a legume. Parasites also exerted a strong direct effect on host performance: host dry mass was negatively correlated with parasite mass for all three host species tested. However, this effect differed among hosts: for E. staechadifolium, proportionately larger parasite mass was correlated with smaller overall biomass of the host and parasite combined, while for the other two hosts, overall host-parasite mass was not correlated with parasite mass, indicating that E. staechadifolium was more affected by parasite attack than were the other host species. Finally, host plant chemistry had strong indirect effects on the performance of an aphid, Nearctaphis kachena, that feeds on C. wightii. Aphids feeding on C. wightii that were parasitizing L. arboreus (alkaloid-producing, high nitrogen), A. pycnocephala (alkaloid-free, intermediate nitrogen), and E. staechadifolium (terpenoid-producing, low nitrogen) experienced 68.2, 65.3, and 49.5% survival, respectively. Further, aphids feeding on parasites using L. arboreus and A. pycnocephala produced 2.43 and 1.77 times more offspring on average than those feeding on parasites using E. staechadifolium. My results indicate that interactions between plant parasites and different host species can have strong direct effects on both host and parasite performance, as well as marked effects on the tritrophic interactions among plant hosts, parasitic plants, and their herbivores.
In the present review, the literature data on the chemical constituents and biological investigations of the genus Pedicularis are summarized. Some species of Pedicularis have been widely applied in traditional Chinese medicine. A wide range of chemical components including iridoid glycosides, phenylpropanoid glycosides (PhGs), lignans glycosides, flavonoids, alkaloids and other compounds have been isolated and identified from the genus Pedicularis. In vitro and in vivo studies indicated some monomer compounds and extracts from the genus Pedicularis have been found to possess antitumor, hepatoprotective, anti-oxidative, antihaemolysis, antibacterial activity, fatigue relief of skeletal muscle, nootropic effect and other activities.
Both the study and management of parasites have historically focused on the control and even elimination, of parasite populations. In contrast, rare parasitic plants represent an uncommon challenge for conservation biologists and managers who often wish to bolster populations of these parasites. Although parasitic plants may suffer any of the maladies known to affect small populations of plants, parasitic plants may also be limited by the additional suite of factors of host availability, host quality, host resistance to parasitism, and parasite preference. We describe studies that have examined parasite growth and reproductive performance with a variety of host species to argue that consideration of the host needs of parasitic plants is necessary for successful conservation of rare species using this mode of resource acquisition. Although it is clear that parasite performance varies greatly with the availability of different host species little is known about the host requirements of most parasitic plants, and the relative importance of particular host species may not immediately be obvious. Further, because published host lists generally do not distinguish minor hosts from those that sustain parasite populations such lists may be misleading for conservation efforts. We argue that successful conservation and restoration of parasitic plants may necessitate the management of thoughtfully selected host populations.
New needle bundles of Picea englemannii (Engelmann spruce) and Picea pungens (blue spruce) contain disubstituted piperidine alkaloids. No alkaloids were found in western spruce budworm larvae (Choristoneura occidentalis), which were feeding on the needles, but needle alkaloids were present in the budworm frass. Excretion of the alkaloids by the budworm larvae, either intact or after a metabolic change, was the common processing pathway. No sequestration could be demonstrated.
The release of alkaloids by barley was quantified by HPLC. Hordenine was released from the roots of barley in a hydroponic system for up to 60 days. The amount reached a maximum, 2μg/plant/day, at 36 days, then declined. Effects on white mustard by hordenine and gramine included reduction of radicle length and apparent reduction in health and vigor of radicle tips. Transmission electron microscopic examination of white mustard radicle tips exposed to hordenine and gramine showed damage to cell walls, increase in both size and number of vacuoles, autophagy, and disorganization of organelles. The evidence of the morphological and primary effects of barley allelochemicals at the levels released by living plants indicates that the biologically active secondary metabolites of barley may lead to a significant role in selfdefense by the crop.
The piperidine alkaloid content of the spruces Picea abies, P. glauca, P. pungens and P. sitchensis, and the pines Pinus edulis, P. flexilis, P. jeffreyi, P. nigra, P. pinea, P. ponderosa and P. sylvestris was assessed by isolation and GCMS. The spruce species contained a variety of cis- and trans-2, 6-disubstituted piperidine alkaloids, while the pines contained only cis-disubstituted piperidines. In some species the alkaloid patterns of individual plant parts were determined. Preliminary bioactivity of some of the piperidines is reviewed.
The indirect effects of hosts on interactions between parasites and other species are not well understood, and it may be difficult to predict the outcome of host species effects on parasite performance due to the complexity of potential direct and indirect effects. For example, parasitic plants obtain defensive compounds as well as nutrients from their hosts, and thus many attributes of parasitic plants are dependent on the quality of their host species. Here I measure the effect of a lupine host species ( Lupinus argenteus) compared to other host species on herbivory, pollination, and female plant fitness in the hemiparasite Indian paintbrush (Castilleja miniata) using a series of field experiments. Association with lupine was determined in the field by assaying Indian paintbrush leaves for lupine alkaloids. I found that Indian paintbrush plants parasitizing lupines experienced reduced herbivory from plume moth larvae, agromyzid fly larvae, and deer, relative to Indian paintbrush plants parasitizing other host species. However, there was no correlation between alkaloid content of inflorescences and plume moth performance. Host species did not affect pollinator preference for Indian paintbrush in the field. Indian paintbrush para- sitizing lupines produced twice as many seeds overall as Indian paintbrush parasitizing other host species. Correlations suggest that this benefit arises both from reduced herbivory and increased nitrogenous resources. The reduction of herbivory in Indian paintbrush plants parasitizing lupines indicates that host species can affect performance of hemiparasites via indirect pathways, and that the larger community of herbivores could alter the impact of a host on its plant parasites.
This chapter provides an update on pyridine and piperidine alkaloids. Cardiovascular effects of nicotine and cotinine have been studied. One study reported an increase in blood pressure in rats when nicotine, cotinine, or nornicotine was administered. A long term study of the effects of cotinine indicated no significant changes in blood pressure, but a decreased heart rate was observed. Nicotine inhibited prostacyclin synthetase in horse aorta microsomes, while cotinine stimulated this enzyme. Both 1 and 5 increased prostaglandin E2 synthesis, while decreasing leukotriene B4 production in polymorphonuclear leukocytes, and decreased thromboxane B2 production in platelet rich plasma. Nicotine and cotinine activated platelet activating factor hydrolase, suggesting a possible role in cardiovascular disease.
This chapter discusses that modern work on alkaloid chemical ecology is highly mechanized, using gas chromatography–mass spectroscopy (GC–MS) or high-performance liquid chromatography (HPLC) with computer libraries of spectra to analyze mixtures and identify compounds. This has multiplied reports on simpler, more volatile, and more variable alkaloids in the studies of chemical ecology, since meaningful data are easy to obtain from these classes with the methods available. Although alkaloid activities are extremely varied and frequently multiple in natural systems, most seem related to the interaction of the lone pair of electrons on nitrogen with DNA synthesis, nerve function, and specific receptors. Enough exceptions are known, however, to be able to predict that many new natural and pharmacological activities of alkaloids have yet to be discovered. The chapter also discusses that it is possible that well-chosen laboratory surrogates for natural herbivores, predators, and pathogens provide reliable data on natural activity. Models are adequate predictors of effects in natural systems, but enough cases of poor correlation are known to cast suspicion on the relevance of laboratory populations to predict ecological activities in the field.
This chapter deals with aspects of the occurrence, the spectroscopic characteristics, and the chemical properties of lupine alkaloids that have been isolated. It includes newly proposed biosynthetic pathway, biotechnological studies, a summary of biological activities, and a discussion of chemotaxonomic aspects of the leguminous plants which accumulate lupine alkaloids. More than 200 naturally occurring lupine alkaloids are known, most of which have been isolated from leguminous plants, especially the subfamily Papilionaceae. A considerable number of lupine-type alkaloids have been found in Papaveraceae, Berberidaceae, Solanaceae, Compositae, Chenopodiaceae, Nymphaeaceae, Ranunculaceae, Scrophulariaceae, Ericaceae, Monimiaceae, Adociidae, and Rubiaceae. The leguminous plants that accumulate the common lupine alkaloids are divided into three main groups: plants which produce the matrine, the lupinine, and the cytisine/sparteine-type alkaloids. There are the Muackia species and a few other species that produce rare bases. Although there is at present no useful drug derived from the lupine alkaloids, except for (+)-sparteine that serves as an oxytociduterotonic, the newly found pharmacological properties of the lupine alkaloids.
Herbivores and pollinators can simultaneously exert selective pressures on plant traits via direct and indirect effects. Net selection on plant traits, such as defensive chemistry, may be difficult to predict from studying either of these interactions in isolation. In this study, alkaloids were manipulated experimentally in the hemiparasitic annual plant Castilleja indivisa (Scrophulariaceae; Indian paintbrush) by growing these parasites with bitter (high-alkaloid) or sweet (low-alkaloid) near-isogenic lines of the host Lupinus albus (Fabaceae) in the field. To evaluate the effect of herbivores, half of the Indian paintbrush plants were randomly assigned to a reduced-herbivory treatment using insecticide, and the other half to a natural-herbivory treatment. Floral traits, bud and fruit herbivory, pollination, alkaloids, and plant performance were measured. These variables were used in a path analysis to dissect the direct and indirect effects of herbivory and pollination on lifetime seed set, and the direct and indirect effects of alkaloids on seed set via herbivory and pollination. Bud herbivory and fruit herbivory directly decreased seed production, whereas pollination had a direct positive effect. In addition, bud herbivory had negative indirect effects on seed set by reducing the number of open flowers, which reduced pollinator visits. Alkaloids directly reduced bud herbivory but did not significantly affect pollination or fruit herbivory directly. However, because bud herbivory indirectly reduced seed set by reducing pollinator visits to flowers, alkaloids also had additional indirect benefits for plants by increasing pollination. Overall, the net benefit of alkaloid uptake was due to both reduction in herbivory and an increase in pollinator visits to flowers. This study demonstrates the importance of considering multiple interactions simultaneously when attempting to understand the mechanisms underlying correlations between plant traits and fitness.
I examined how the performance of Castilleja wightii (Scrophulariaceae), a generalist root parasite, is affected by the availability of different combinations of host species. In this greenhouse study, I focused on pairs of hosts consisting of either two leguminous host individuals (Lupinus arboreus; Fabaceae), two non-nitrogen-fixing hosts (Eriophyllum stachaedifolium; Asteraceae), or one individual of each of these species. Castilleja growth and reproductive performance were greatly improved by the simultaneous attack of two distinct host species, even though Castilleja grown with two Lupinus hosts had significantly higher nitrogen content. Different combinations of host species also strongly affected the growth of aphid colonies feeding on the Castilleja used in this experiment. Across all treatments, the growth of aphid colonies was positively correlated with the nitrogen content of the parasitic plants, which, in turn depended on the combination of hosts attacked. Aphid colonies feeding on parasites attacking a mixture of host species grew more slowly than those on parasites attacking two Lupinus individuals. Therefore, simultaneous attack of a mixture of host species may lead to improved parasite performance in two ways - via a direct benefit on parasite growth and flowering as well as a possible indirect benefit because of the relatively poor performance of herbivores feeding on these parasites.
Arising from annual variation in parasitic plant population densities, substantial yearly changes may occur in the parasitic load of an individual perennial host. We conducted two two-year greenhouse pot experiments to examine the effects of varying intensities and duration of infection by an annual root hemiparasitic plant. Rhinanthus serotinus, on the growth and reproduction of its perennial host grass. Agrostis capillaris. In the first experiment, one host plant was growing either alone or under a load of 1 or 3 root hemiparasitic plants for one growing season, and during the next season all hosts continued their life free of hemiparasites. In the second experiment, the host plants either grew alone or were parasitised by 1 or 2 root hemiparasitic plants either during the first growing season only or during two successive seasons (the parasitic load being the same in the two seasons). In both experiments, the root hemiparasites markedly reduced the growth and reproduction of their perennial hosts. In the first experiment, the negative effects of parasites on host performance increased with the increase in intensity of parasitic infection from one to three parasites. The harmful effects of hemiparasitim were carried over to the following season; hosts parasitised during the previous season with one or three parasites produced significantly less biomass than those without parasites. In addition, hosts parasitised by three parasites during the first season produced significantly less panicles in the second season than those parasitised by one parasite and those without parasites. The second experiment showed that the production of biomass of A. capillaris during the second season was, but the production of panicles was not affected by the duration of parasitic infection. In addition, in this experiment, the second season biomass of A. capillaris depended on the intensity of infection (1 vs 2 parasites), but the production of panicles was unaffected by the number of parasites.
Alkaloids found in Picea breweriana include hygrine, hygroline, N-methylsedridine and N-methylpelletierine. This represents the first isolation of these alkaloids from the Pinaceae. Euphococcinine, an alkaloid previously found in Picea and Pinus species, is also present. The presence of alkaloids characteristic of two different biosynthetic pathways in P. breweriana highlights the apparent uniqueness of this species.
A new diastereoselective synthesis of 2,6-disubstituted piperidinic alkaloids is presented. Three natural compounds, the (−)-pinidinone 1a, the (+)-dihydropinidine 1b and the (−)-pinidinol 1c were prepared from optically pure (6R)-6-methylpiperidin-2-one 2. This method is based on the chemo- and diastereocontrolled reductions of an exocyclic β-enamino ketone.
To examine the mediation of host-predator interaction by a parasite, we studied the three-level interactions among a host plant, a root hemiparasitic plant, and their common predator, a generalist snail herbivore. The host species, Trifolium repens, is able to synthesize cyanogenic glucosides that have a significant role in plant herbivore resistance. Some T. repens populations are polymorphic with respect to cyanogenesis. Our second aim was to examine whether the mediation of the host plant-herbivore interaction by the parasitic plant could affect the maintenance of the cyanogenic polymorphism. The parasitic plant (Rhinanthus serotinus) was equally harmful to cyanogenic and acyanogenic hosts and grew equally well on both host types. In a no-choice experiment, both cyanogenesis and root hemiparasitism of the host plant reduced the growth of the herbivore (Arianta arbustorum). The herbivores consumed less leaf area of the parasitized plants than of unparasitized plants, but only when the host plant was acyanogenic. In a multiple-choice experiment, the snails were similarly affected by cyanogenesis but not by parasitic infection of the host. Thus, there was a discrepancy between food choice and performance of the herbivore. Our results suggest that the overall effects of the parasitic plant on the host plant were ameliorated through the indirect effects of the parasitic infection on herbivore performance and food consumption. This indirect effect of the parasitic infection seemed to be more beneficial for the acyanogenic plants: if parasitized, the leaf area of acyanogenic plants consumed by the herbivore was 45% higher than that of cyanogenic plants, whereas in unparasitized plants the corresponding figure was 114%. Thus, parasitism may decrease the advantage cyanogenic plants gain through decreased herbivory. Further, in mainly cyanogenic T. repens populations, cyanogenesis might be a more important feeding deterrent than root parasitism; whereas in mainly acyanogenic populations root parasitism might be relevant to herbivore-T. repens interactions. We are the first to document the effects of a plant parasite on the performance of both the host plant and a host-feeding herbivore. Our results highlight the need to look beyond the direct effect of parasites on their hosts.
A single crystal X-ray study on the 4-bromophenylthiocarbamate derivative of (-)-pinidinol hydrochloride established the stereostructure of this alkaloid from Picea engelmannii as (2R,6R)-2-methyl-6-[(2R)-2-hydroxypropyl)]piperidine [2].
New iridoids were isolated from Orthocarpus purpurascens (6-beta-hydroxyboschnaloside {4}) and Orthocarpus attenuatus (8-deoxylamiol {6} and 5,8-bisdeoxylamiol {7}), while the novel phenylpropanoid glycoside 2-O-acetylrossicaside A {8} was found in Orthocarpus densiflorus var. gracilis. Known iridoid and phenylpropanoid glycosides were also isolated from these species and from O. densiflorus var. densiflorus and Orthocarpus erianthus. Surprisingly, Orthocarpus lithospermoides var. bicolor appeared to be devoid of iridoids but contained large amounts of echinacoside, a phenylpropanoid glycoside not found in any other Orthocarpus. The results appear to be in general agreement with recent suggestions that O. purpurascens, O. attenuatus, O. densiflorus, and O. erianthus be moved from Orthocarpus to Castilleja. The lamiols in O. attenuatus are highly anomalous for the Scrophulariaceae, and they could arise from root parasitism of O. attenuatus on lamiol-containing species of the Labiatae. Pyridine monoterpene alkaloids, found in other Orthocarpus, were not encountered, but quinolizidine alkaloids from root parasitism on Lupinus species were isolated.
A series of 2,6-disubstituted piperidine alkaloids have been isolated from several Pinus (pine) and Picea (spruce) species and characterized structurally. The pines appear to contain only cis-disubstituted piperidines, while the spruces contain both cis- and trans-disubstituted piperidines. The structural relationships among the alkaloids suggest a plausible biosynthetic scheme and a reason why previous attempts to elucidate the biosynthesis of pinidine failed beyond establishing its polyketide origin. A mixture of alkaloids from needles of Pinus ponderosa proved to be highly teratogenic. The alkaloids might therefore be involved in so-called pine needle abortion which occurs in pregnant range cows which feed on Ponderosa pine needles.
Starting from 1,6-heptadiene, two AD reactions in a stepwise manner lead to the anti-1,5-diol and syn-1,5-diol stereodivergently, which have been converted by aminocyclization into trans- and cis-2,6-disubstituted piperidines (trans- and cis-12), respectively. The first total synthesis of (+)-9-epi-6-epipinidinol (2) and (−)-pinidinol (3) has been achieved from trans- and cis-12.
Castilleja integra was seeded in a pot of mature Penstemon teucrioides and allowed to grow to blossom stage as a root parasite on Penstemon. Aucubin, which is the major iridoid of the P. teucrioides root but which is normally lacking from C. integra, was isolated from the above-ground parts of the parasitic C. integra. The major iridoid glycosides of P. teucrioides leaves were aucubin, isoscrophularioside (10-O-cinnamylaucubin) and trans-eurostoside (10-O-p-hydroxycinnamylaucubin). The two cinnamyl esters from the leaves of P. teucrioides were not found in C. integra. This is the first demonstration of iridoid glycoside transmission from a root host plant to a parasitic plant.
Castilleja (Scrophulariaceae) species of the western United States contain pyrrolizidine and quinolizidine alkaloids. TheCastilleja obtain the alkaloids by root parasitism on host plants, withSenecio atratus andS. triangularis (Asteraceae) furnishing the pyrrolizidines, and quinolizidines being obtained fromLupinus species andThermopsis montana (Leguminosae). Individual plants within a givenCastilleja species population may be devoid of alkaloids while others have high alkaloid content. No populations have been found which are made up of both pyrrolizidine- and quinolizidine-containing individuals. These results have important implications forCastilleja ecology, for the study of insect herbivores which areCastilleja specialists, and in the development of systems for the investigation of the role of alkaloids as plant defenses.
2-Methyl-6-(2-hydroxypropyl)pyridine (2) was obtained by reaction of the monolithium salt of 2,6-lutidine with acetaldehyde. Hydrogenation of the hydrochloride of 2 yielded cis-2-methyl-6-(2-hydroxypropyl)piperidine as a pair of diastereomers. Heating this alcohol with potassium bisulfate afforded (±)-pinidine, which was resolved with optically active 6,6′-dinitrodiphenic acid. [10- 14C]-5,9-Dioxodecanoic acid was prepared and fed to Pinus jeffreyi plants, as a potential precursor of pinidine. However, there was no significant incorporation of activity into the alkaloid, indicating that this compound is probably not an intermediate between acetate and pinidine.
Alkaloid profiles of extracts of fourteen papilionaceous species in the tribes Thermopsideae and Genisteae (sensu Polhill) have been determined. Altogether, eighteen quinolizidine alkaloids, representative of four structural groups, and one dipiperidine alkaloid were identified among the legumes studied. The chemotaxonomic implications of these data are discussed.
The alkaloids of Thermopsis montana Nutt. were isolated by means of preparative tlc and identified by comparative infrared spectroscopy, melting points of derivatives and co-chromatography. Cytisine, hydroxylupanine, N-methylcytisine, anagyrine and thermopsine were separated and identified. The trace compounds lupanine and 17-oxosparteine were tentatively identified, while sparteine and genisteine were found to be absent. The seasonal variation of the identified alkaloids was studied both qualitatively and quantitatively.