Chondrilla Juncea Research Articles

Pattern of callose deposition during the course of meiotic diplospory in Chondrilla juncea (Asteraceae, Cichorioideae)

Total absence of callose in the ovules of diplosporous species has been previously suggested. This paper is the first description of callose events in the ovules of Chondrilla juncea, which exhibits meiotic diplospory of the Taraxacum type. We found the presence of callose in the megasporocyte wall and stated that the pattern of callose deposition is dynamically changing during megasporogenesis. At the premeiotic stage, no callose was observed in the ovules. Callose appeared at the micropylar pole of the cell entering prophase of the first meioticdivision restitution but did not surround the megasporocyte. After the formation of a restitution nucleus, a conspicuous callose micropylar cap and dispersed deposits of callose were detected in the megasporocyte wall. During the formation of a diplodyad, the micropylar callose cap decreased and the walls of a newly formed megaspores showed scattered distribution of callose. Within the older diplodyad, callose was mainly accumulated in the wall between megaspores, as well as in the wall of the micropylar cell; however, a dotted fluorescence of callose was also visible in the wall of the chalazal megaspore. Gradual degradation of callose in the wall of the chalazal cell and intense callose accumulation in the wall of the micropylar cell were related to the selection of the functional megaspore. Thus, our findings may suggest that callose fulfills a similar role both during megasporogenesis in sexual angiosperms and in the course of meiotic diplospory in apomicts and seems to form a regulatory interface between reproductive and somatic cells.

Nutrient composition of six wild edible Mediterranean Asteraceae plants of dietary interest

Interest in wild leafy vegetables has significantly increased in Europe, and elsewhere, because they provide high nutrient levels and potential health benefits. Some Asteraceae species are widely cultivated, and many non-cultivated species are also traditionally eaten as green vegetables; however, the information on their nutrient composition is scarce. This study presents useful data (proteins, fat, available carbohydrates, soluble/insoluble fibre and mineral content) of interest for furthering the knowledge of the nutritional value of six wild Asteraceae species traditionally consumed in many areas in Mediterranean countries. These rarely studied species are Taraxacum obovatum (Willd.) DC., Chondrilla juncea L., Sonchus oleraceus L., Cichorium intybus L., Scolymus hispanicus L. and Silybum marianum (L.) Gaertn. From the results obtained, these species are notable for their high fibre content (2.3–13.4g/100g), K (375–1772mg/100g) and Ca (16–472mg/100g), compared to most conventional vegetables. C. juncea can contribute to fibre and micronutrient intakes, particularly Mn (with values of up to 50% of daily Recommended Dietary Allowances for adults). These new findings suggest that these plants can be considered as valuable food resources in the traditional Mediterranean diet, allowing their incorporation into food nutrient databases.

DETERMINATION OF ENVIRONMENTAL FACTORS AND INDICATOR SPECIES AFFECTING THE DISTRIBUTION OF Origanum onites L.: A CASE STUDY FROM THE LAKES DISTRICT, TURKEY

Factors influencing the distribution of Origanum onites L., (locally known as Turkish oregano) were analyzed on the Lakes District of Turkey, using Two-tailed Wilcoxon s runk sum statistics and Pearson chi-square .2 test contained in the SPSS 17.0 package. An inter-specific correlation analysis (ICA) was also applied to determine indicator plant species of O. onites. Analyses performed on environmental factors showed that there is a relatively high correlation between the occurance of Turkish oregano and soil texture. Besides, our results showed that species richness plays a key role in plant distribution. According to ICA, Allium myrianthum Boiss., Astragalus prusianus Boiss., Centaurea cariensis Boiss. subsp. maculiceps (O.Schwarz) Wagenitz, Chondrilla juncea L. var. juncea L., Leontodon asperima (Willo) J. Ball and Putoria calabrica (L.fil) DC., were found as the most positive indicator plant species, and Fontanesia philliraeodies Labill subsp. philliraeodies, Juniperus communis L. var. nana Syme., were found as the most negative indicator plant species for the distribution of Turkish oregano.

Mediterranean non-cultivated vegetables as dietary sources of compounds with antioxidant and biological activity

Non-cultivated vegetables whose basal leaves have been traditionally consumed in Spain were evaluated for their potential in human nutrition, considering vitamin C, organic acids, tocopherols, phenolics and flavonoids, and antioxidant activity. As far as we know, this is the first report on organic acids and vitamin C of Anchusa azurea and Apium nodiflorum, on tocopherols of Aazurea, Beta vulgaris, Chondrilla juncea, Rumex papillaris, Rumex pulcher, Silybum marianum and Taraxacum obovatum, as well as on the antioxidant capacity of most of them. Data revealed that the mentioned non-cultivated vegetables are good sources of bioactive compounds. R. pulcher, R. papillaris and Papaver rhoeas are rich in vitamin C, Sonchus oleraceus and R. papillaris in tocopherols. R. pulcher, P. rhoeas and A. azurea showed promising antioxidant properties, which are related to their high levels of phenolic and flavonoids. Some species presented high levels of oxalic acid. Therefore, people with a trend of developing kidney calculus should avoid eating these greens (especially S. marianum, S. oleraceus and Beta maritima) and choose species with low oxalic acid content such as T. obovatum and Cichorium intybus. The traditional consumption of these species after boiling and rejecting the water may decrease the amount of oxalic acid.

Propagule pressure, genetic structure, and geographic origins of Chondrilla juncea (Asteraceae): An apomictic invader on three continents

Assessing propagule pressure and geographic origins of invasive species provides insight into the invasion process. Rush skeletonweed (Chondrilla juncea; Asteraceae) is an apomictic, perennial plant that is invasive in Australia, South America (Argentina), and North America (Canada and the United States). This study comprehensively compares propagule pressure and geographic structure of genotypes to improve our understanding of a clonal invasion and enhance management strategies. • We analyzed 1056 native range plants from Eurasia and 1156 plants from three invaded continents using amplified fragment length polymorphism (AFLP) techniques. We used measures of diversity (Simpson's D) and evenness (E), analysis of molecular variance, and Mantel tests to compare invasions, and genotype similarity to determine origins of invasive genotypes. • We found 682 unique genotypes in the native range, but only 13 in the invaded regions. Each invaded region contained distinct AFLP genotypes, suggesting independent introduction events, probably with different geographic origins. Relatively low propagule pressure was associated with each introduction around the globe, but levels of among-population variation differed. We found exact AFLP genotype matches between the native and invaded ranges for five of the 13 invasive genotypes. • Invasion dynamics can vary across invaded ranges within a species. Intensive sampling for molecular analyses can provide insight for understanding intraspecific invasion dynamics, which can hold significance for the management of plant species, especially by finding origins and distributions of invasive genotypes for classical biological control efforts.

Fatty acids profiles of some Spanish wild vegetables

Polyunsaturated fatty acids play an important role in human nutrition, being associated with several health benefits. The analyzed vegetables, in spite of its low fat content, lower than 2%, present a high proportion of polyunsaturated fatty acids of n-3, n-6 and n-9 series, such as α-linolenic, linoleic and oleic acids, respectively. Wild edible plants contain in general a good balance of n-6 and n-3 fatty acids. The present study tries to contribute to the preservation and valorization of traditional food resources, studying the fatty acids profile of 20 wild vegetables by gas-liquid chromatography with flame ionization detection. Results show that species in which leaves are predominant in their edible parts have in general the highest polyunsaturated fatty acid/saturated fatty acid ratios: Rumex pulcher (5.44), Cichorium intybus (5.14) and Papaver rhoeas (5.00). Due to the low n-6/n-3 ratios of the majority of the samples, they can be considered interesting sources of n-3 fatty acids, especially those with higher total fat amount, such as Bryonia dioica, Chondrilla juncea or Montia fontana, with the highest contents of α-linolenic acid (67.78, 56.27 and 47.65%, respectively). The wild asparaguses of Asparagus acutifolius and Tamus communis stand out for their linoleic acid content (42.29 and 42.45%, respectively). All these features reinforce the interest of including wild plants in diet, as an alternative to the variety of vegetables normally used.

The potential of beneficial microorganisms in agricultural systems

The potential of beneficial microorganisms in agricultural systems

Uptake, translocation and metabolism of aminocyclopyrachlor in prickly lettuce, rush skeletonweed and yellow starthistle

Aminocyclopyrachlor is a new herbicide proposed to control broadleaf weeds and shrubs in non-crop and rangeland systems. To gain a better understanding of observed field efficacy, the uptake and translocation of foliar-applied aminocyclopyrachlor (DPX-MAT28) and aminocyclopyrachlor methyl ester (DPX-KJM44) were evaluated in two annuals, prickly lettuce (Lactuca serriola L.) and yellow starthistle (Centaurea solstitialis L.), and one perennial, rush skeletonweed (Chondrilla juncea L.). Absorption and translocation varied between species. While absorption of DPX-KJM44 was greater than absorption of DPX-MAT28, rush skeletonweed absorbed the most, followed by yellow starthistle and prickly lettuce. Overall, the total translocation of either herbicide was highest in yellow starthistle, followed by rush skeletonweed and prickly lettuce. Proportional herbicide movement between species was similar, with the majority translocating to developing shoots. However, in rush skeletonweed, early translocation was directed to root tissue. In rush skeletonweed, no DPX-MAT28 metabolism occurred, while DPX-KJM44 was rapidly de-esterified and translocated as DPX-MAT28. Aminocyclopyrachlor absorption and translocation are dependent on active ingredient structure and species sensitivity. Highly sensitive species such as prickly lettuce absorb and translocate less material than relatively less sensitive species such as rush skeletonweed. De-esterification of DPX-KJM44 appears to delay translocation of the resulting acid in yellow starthistle and rush skeletonweed.

The consumption of wild and semi-domesticated edible plants in the Arribes del Duero (Salamanca-Zamora, Spain): an analysis of traditional knowledge

The collection and consumption of wild (including naturalized) and semi-domesticated (cultivated and reverted to wild status, and neglected cultivated plants for food) edible plants in the rural communities of the Arribes del Duero (western Spain), a highly heterogeneous Mediterranean agroecosystem, were analysed. Through semi-structured interviews with 80 informants, data on the gathering, preparation and consumption of 76 wild edible plant species were acquired. To analyze how traditional knowledge varies with the characteristics of the informants, we performed an ANCOVA. The “age” variable was found to have a significant effect. The most frequently cited species in the study area (i.e. Rubus ulmifolius, Foeniculum vulgare, Quercus ilex, Laurus nobilis, Origanum vulgare) are widely consumed in the Mediterranean region. Also, from a cluster analysis it was observed that the grouping succession this territory matches those of analysed areas of the Iberian southwest. Certain species have traditionally been consumed as an important supplement to the diet, particularly during food shortages (i.e. Rumex induratus, Chondrilla juncea). Several species are ethnobotanical novelties, among which are Erodium botrys and Astragalus pelecinus, whose immature fruits are eaten raw as a snack. Some ecological and cultural aspects of the gathering of wild plants for food are discussed.

Interaction effects of two biological control organisms on resistant and susceptible weed biotypes of Chondrilla juncea in western North America

Interactions between natural enemy species may modify their net effect on host plants, but little research has been done to examine how plant resistance influences species interactions in biological weed control. We performed common garden experiments with clonal accessions of Chondrilla juncea to compare a rust-susceptible weed biotype with a rust-resistant biotype, both of which are invasive in western North America. Inoculations with two biological control organisms, a rust fungus pathogen ( Puccinia chondrillina) and an eriophyid gall mite ( Eriophyes chondrillae), were applied separately and in combination to test if plant performance is modified by antagonistic or facilitative species interactions. We found no significant rust × mite interaction effects for several plant traits (shoot length, shoot dry biomass, fecundity, rosette growth, and rosette senescence), and therefore the two natural enemies appear to have independent and complementary effects on plant performance. As expected, genetic resistance of weed biotypes modified the effects of rust disease on shoots and rosettes, although not for plant fecundity. We found no significant biotype × mite effects on plant performance traits. However, rust inoculation reduced the total dry biomass of mite galls in the rust-susceptible biotype by indirect competition due to decreased growth of diseased shoots, but not in the rust-resistant biotype. Our results indicate that rust disease may have the potential to modify mite gall epidemiology and relative plant performance in mixed populations of resistant and susceptible C. juncea biotypes, though at present the geographic distributions of these North American biotypes are mainly separate.

Seasonal Change in Forage Value of Rangeland Weeds in Northern Idaho

AbstractPrescribed grazing is an effective tool for controlling some rangeland weeds. Forage quality of eight nonnative rangeland weeds common to northern Idaho was determined. Five collection sites were established for each weed species: rush skeletonweed, meadow hawkweed, houndstongue, sulfur cinquefoil, yellow starthistle, Dalmatian toadflax, hoary cress, and tansy ragwort. Plants were collected at rosette, bolt, flower, and seed set stages; dried and separated into leaves, stems, flowers, or seed; and analyzed separately for crude protein (CP), neutral detergent fiber (NDF), and mineral content (ash). As expected, plants became more fibrous as they matured because stems increased in NDF value throughout the season and the leaf : stem ratio of most weeds we examined decreased throughout the season. In general, the weeds we examined expressed only moderate fiber levels, beginning the season with NDF values near 34% in the rosette stage and becoming near 52% NDF in the seed set stage. CP values were near 25% in the rosette stage for houndstongue, rush skeletonweed, and hoary cress whereas other weeds we examined had about 15% CP in the rosette. As the season advanced, all plants lost protein content and ended the season with CP values from 5 to 8% at seed set. Ash values declined for all species as the season progressed. Our results indicate that these weeds have forage values similar to many native plants and could be reasonable forage resources for livestock. We did not examine the content of secondary compounds in these weeds that may render them unpalatable and limit their forage value.

Postfire Invasion Potential of Rush Skeletonweed (Chondrilla Juncea)

North American sagebrush steppe communities have been transformed by the introduction of invasive annual grasses and subsequent increase in fire size and frequency. We examined the effects of wildfires and environmental conditions on the ability of rush skeletonweed (Chondrilla juncea L.), a perennial Eurasian composite, to invade degraded sagebrush steppe communities, largely dominated by cheatgrass (Bromus tectorum L.). Recruitment of rush skeletonweed from seed and root buds was investigated on 11 burned and unburned plot pairs on Idaho's Snake River Plain following summer 2003 wildfires. Emergence from soil seedbanks was similar on burned and unburned plots in 2003 and 2004 (P = 0.37). Soils from recently burned plots (P = 0.05) and sterilized field soil (P < 0.01) supported greater emergence than did unburned field soils when rush skeletonweed seeds were mixed into the soils in the laboratory. These decreases may indicate susceptibility of this exotic invasive to soil pathogens present in field soils. Seeds in bags placed on field soil in late October 2003 reached peak germination by mid-January 2004 during a wet period; 1% remained viable by August 2004. Seedling emergence from sown plots or the native seedbank and establishment of new rosettes from root sprouts in 2003–2005 indicate that seed germination of rush skeletonweed on the Snake River Plain may be facultative, occurring in fall or spring if soil moisture is adequate, although many germinants may not survive. Stand development results primarily from root sprouting. Establishment from seed is episodic but provides for dispersal, with increasing fire frequency and size expanding the areas of disturbance available for new invasions.

GALL FORMATION ON THE DIFFERENT FORMS OF SKELETON WEED BY CYSTIPHORA SCHMIDTI RÜBSAAMEN (DIPTERA: CECIDOMYIIDAE)

Cystiphora schmidti produced similar numbers and densities of galls on the 3 Australian forms of its host weed Chondrilla juncea. The total number of galls increased with available leaf area. Density of galls was similar on all leaf areas offered. Low temperature significantly reduced the number and density of galls on all forms of the weed.

Rzadsze rośliny naczyniowe terenów kolejowych w określonych regionach Kotliny Sandomierskiej. Cz I. Nizina Nadwiślańska, część północna

The present study is one of the first that are devoted to previously unknown stations of the more interesting flora of vascular plants discovered in the railway areas in specific regions of the Sandomierz Basin. Stations of 112 plant species of this type were currently described, which are located in the railway areas in the Sandomierz Basin in the northern part of the Vistula Lowland. Among the plants investigated, apophytes (69 species) prevail over anthropophytes (33 species). Moreover, there are presented stations of nine taxa of different rank of genus Oenothera plants with an unknown history of their settlement in the territory of Poland. They are generally plants with stations recorded with varying frequency on a regional and national scale. The most interesting and rarest of these in the Sandomierz Basin include above all: Althea hirsuta, Bromus japonicus, B. rigidus, Chondrilla juncea, Cirsium canum, Fumaria muralis, Euphorbia lucida, Erysimum marschallianum, Galium rubioides, Gladiolus paluster, Gratiola officinalis, Linaria genistifolia, Oenothera coronifera, Oe. fallax, Oe. hoelscheri, Oe. parviflora, Ononis spinosa, Potentilla intermedia, Roripa x armoracioides, Sedum reflexum, Silene latifolia, S. otites.

Winter mortality of Aceria chondrillae, a biological control agent released to control rush skeletonweed (Chondrilla juncea) in the western United States

Abstract: Classical biological control of weeds is based on the assumptions that: (1) plant species are in part invasive in their introduced range because of the absence of coevolved specialist herbivore arthropods and plant pathogens; and (2) that these specialist herbivores can regulate host‐plant populations. Although the need for quantitative post‐release monitoring studies testing these assumptions has been acknowledged repeatedly, the number of assessments is still remarkably small and usually restricted to systems with notable impact of an agent species. However, studying systems where biological control agents cause no observable target weed reductions may be important to identifying factors that limit the population size or impact of biological control agents. Three biological agents were released for the control of the herbaceous perennial rush skeletonweed, Chondrilla juncea in North America between 1975 and 1977. Although all three species are widely established, weed densities are increasing and there is little quantitative information on factors limiting biological control efficacy. We examined the winter biology and survivorship of the rush skeletonweed gall mite Aceria chondrillae at two rush skeletonweed field sites in south‐western Idaho over 2 years. Gall mite winter mortality was high (&gt;90%) in both years and for both sites. Gall mites were more abundant on plants that produced rosettes in fall and rush skeletonweed plants growing on southern aspect were 3.4 times more likely to produce rosettes than those growing on northern aspects. Our data suggest that A. chondrillae population densities are limited by its high winter mortality. The gall mites may require fall rosettes to successfully survive the winter, which are commonly absent on north‐facing aspects, impairing the efficacy of A. chondrillae to control rush skeletonweed in the intermountain western United States.

On the occurrence of the guaianolide glucoside ixerin F in Chondrilla juncea and its chemosystematic significance

On the occurrence of the guaianolide glucoside ixerin F in Chondrilla juncea and its chemosystematic significance

Evaluation of weed eradication programs: the delimitation of extent

ABSTRACTEradication is a management strategy that can provide substantial ecological and economic benefits by eliminating incursions of pest organisms. In contrast to eradication efforts that target other pests, weed eradication programs can be very protracted owing to the presence of persistent seed banks and difficulties in detecting the target. Hence there is a need to develop criteria to assist in the evaluation of progress towards eradication. Knowledge of the extent of a weed incursion (the ‘delimitation’ criterion) is considered fundamental for eradication success, as an incursion will progress from any infestations that remain undetected and thus uncontrolled. This criterion is examined with regard to eradication programs targeting Bassia scoparia L. A.J. Scott [= Kochia scoparia L. Schrader], Chondrilla juncea L. (both in Western Australia) and Orobanche ramosa L. in South Australia. The B. scoparia incursion, which has been eradicated, was largely delimited within 12 months of the inception of its eradication program. In contrast, the Western Australian C. juncea incursion has never been delimited, owing to insufficient investment in surveillance during an eradication program spanning 30 years. An exponential decrease in the detection ratio (infested area detected/area searched) over time suggests that delimitation has been approached within 6 years of the inception of the eradication program for O. ramosa. An effective surveillance program is essential for achieving delimitation of a weed incursion.

Effect of the rust fungus Puccinia chondrillina TU 788 on plant size and plant size variability in Chondrilla juncea

Summary Chondrilla juncea is one of the most serious introduced weed species in Australia. Successful biological control has been achieved by the release of the rust fungus Puccinia chondrillina. Although P. chondrillina is thought to reduce the competitive ability of C. juncea by reducing plant size, the precise mechanism by which the pathogen controls its host is poorly understood. In this experiment, we examined the effect of P. chondrillina TU 788 infection on individual plant size, and size variability, in two genotypes (one resistant, one susceptible) of C. juncea. Exposure to P. chondrillina significantly reduced the average size of susceptible C. juncea plants, a reduction apparent in both roots and shoots. Plant size variability of the susceptible C. juncea genotype was also reduced by P. chondrillina. Plant size, and plant size variability of the resistant genotype were unaffected by exposure to rust, or association with rust‐affected plants. The effect of P. chondrillina on plant size in rust‐susceptible C. juncea plants shows how effective bio‐control of this weed may occur in field populations.

In vitro antioxidant activity of non-cultivated vegetables of ethnic Albanians in southern Italy.

A total of 27 extracts from non-cultivated and weedy vegetables traditionally consumed by ethnic Albanians (Arbëreshë) in the Vulture area (southern Italy) were tested for their free radical scavenging activity (FRSA) in the DPPH (1,1-diphenyl-2-picrylhydrazil radical) screening assay, for their in vitro non-enzymatic inhibition of bovine brain lipid peroxidation and for their inhibition of xanthine oxidase (XO). In both antioxidant assays strong activity was shown for Leopoldia comosa (bulbs, syn.: Muscari comosum) and Centaurea calcitrapa (young whorls). In the lipid peroxidation assay, extracts from leaves of Origanum heracleoticum, Urtica dioica and Tordylium apulum showed a remarkable inhibitory activity (> 50%), too. In the case of Leopoldia comosa and Origanum heracleoticum this activity was comparable to quercetin (at a concentration of 50 microM) and Rhodiola rosea extract. Extracts from non-cultivated Cichorium intybus, Chondrilla juncea and Stellaria media showed strong in vitro inhibition of xanthine oxidase, with an activity higher than that of a reference extract from Ledum groenlandicum. These findings suggest that weedy vegetables may be useful antioxidants of interest in the prevention of ageing related diseases, CNS disorders and as potential sources of phytomedicines against hyperuricaemia and gout.

Seed Biology of Rush Skeletonweed in Sagebrush Steppe

Rush skeletonweed (Chondrilla juncea L.) is an invasive, herbaceous, long-lived perennial species of Eurasian or Mediterranean origin now occurring in many locations throughout the world. In the United States, it occupies over 2.5 million ha of rangeland in the pacific Northwest and California. Despite the ecological and economic significance of this species, little is known of the ecology and life history characteristics of North American populations. The purpose of this study was to examine seed germination characteristics of 2 populations of rush skeletonweed in Idaho. Seeds from rush skeletonweed plants in southwestern Idaho were collected during the 1994 and 1995 growing seasons. Mature seeds were harvested on 6 dates between early July and early October 1994, and on 5 dates between early July and late September 1995. Fresh seeds from each harvest period were measured to determine seed weight, total germination, rate of germination, and viability (tetrazolium staining [TZ]) of non-germinating seeds. An aliquot of seeds collected in 1994 was also stored for 1 year to examine the effects of seed storage on germination. In southwestern Idaho, rush skeletonweed produces seeds continuously from mid-July through October. Seeds were capable of immediate germination without scarification or wet prechilling. Total germination generally ranged from 60 to 100% throughout the entire seed production period. Germination was also rapid, reaching 50% of total germination in less than 12 days. In general, germination was higher at the lower incubation temperature regime (20/10 degrees C), perhaps reflecting origins of this species in Mediterranean winter rainfall regions. The TZ testing indicated that 30 to 60% of non-germinating seeds were viable, suggesting that seeds may persist in the soil seed bank. Up to 60% of seeds remained viable following 1 year of storage. Stored seeds generally exhibited higher germination rates (average = 90%) than fresh seeds (average = 67%), indicating possible dormancy and afterripening effects. Germination characteristics of this species are consistent with those of other invasive alien species, and favor rapid population growth leading to community dominance. DOI:10.2458/azu_jrm_v53i5_liao