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Phenotypic correlations were calculated and the levels of phenotypic integration of three congeneric species, annual Lamium purpureum and perennial Lamium album and Lamium maculatum, were estimated. Calculations were performed separately for different stages of development during transplantation under different density and light treatments. L. purpureum exhibited greater integration in comparison to the other two species before exposure to environmental treatments, as well as greater variability in phenotypic correlations in response to light and density. The perennial species possessed similar correlation patterns in comparison to annual L. purpureum, becoming more similar to L. purpureum at later stages of development. The effects of density and light intensity were dependent on the specific combination of factors, as well as on the species under study. Density effects in L. purpureum were also habitat- and population-specific. A greater difference in response to density treatments between habitats than between populations was detected. Overall, phenotypes become more integrated during ontogeny, while dissimilarities in phenotypic correlations among species and between populations were more related to ecological than to phylogenetic differences.

Rationale: Water loss by evaporation is a normal physiological process, in order to regulate plant temperature. Under conditions of thermal and water stress, water loss is accelerated compared to normal conditions, and the response of plants is variable. In extreme cases, it can lead to wilting and death of plants. It was found that the phenomenon of water loss behaved as a pattern in different plant species, given by two functions, logistics (first part of water loss) and hyperbola (second part of water loss) in relation to a moment m, at which the rate of water loss (RWL) has reached its maximum value. Method: We studied the water loss process for a series of plant samples on different plant species (Picea abies L., H. Karst; Juniperus communis L.; Pinus silvestris L.; Thuja occidentalis L.; Lamium purpureum L.; Veronica hederifolia L.), measuring the rate of weight loss (RWL) in controlled conditions. The drying of the samples was done in identical conditions (thermo-balance, 100 °C, standard temperature for drying the plant samples) with the real-time recording of the drying time simultaneously with the water loss rate (RWL) from the plant samples. The exposure time varied, depending on each species sample, and was approximately 1000 s. Results: The experimental data was recorded at intervals of every 10 s, during the entire drying period. RWL values varied from 0.024 to 0.054 g/min at the beginning of the drying process and reached maximum values after 70–100 s, having values between 0.258 g/min and 0.498 g/min. During the drying period, this indicator presented different graphic evolutions, difficult to be described with a single function. The first segment was described by a logistic function, and the second was described by a hyperbola, resulting in a model (RWLMod) which described the real phenomenon. This model and theoretical calculation were used to quantify the water loss in a time interval and, compared with empirical dates, no significant differences were observed, which indicated an increased degree of accuracy regarding the use of this model. Recommendation and novelty of work: The novelty of the work is given by the obtained model (RWLMod), which makes possible the description of RWL over the entire time interval, and ensures a good fit with the real data. It recommends the method and model in studies of plant behaviour under stress in relation to different influencing factors.

Soybean cyst nematode (SCN) (Heterodera glycines) commonly infests soybean (Glycine max), but has also been reported to infest haricot bean, mung bean, adzuki bean, some species of Lespedeza and Melilotus (3), purple deadnettle (Lamium purpureum), henbit (Lamium amplexicaule), field pennycress (Thlaspi arvense), and shepherd's-purse (Capsella bursa-pastoris) (4). During 2009 to 2011, a survey for plant parasitic nematodes on tobacco was made in Xuchang, Henan Province, central China. Thirty six percent of 50 tobacco fields showed yellowing symptoms, and females and cysts of cyst-forming nematode were observed in the yellowing tobacco roots. The cysts were characterized by a lemon shape, with posterior protuberance, ambifenestrate, bullae, and underbridge present. The key morphometrics of cysts were fenestra length (38 to 44 μm) and width (34 to 40 μm), vulval silt (41 to 50 μm), and underbridge length (73 to 99 μm), all of which were similar to SCN (1). DNA was extracted by putting a single cracked cyst collected from the tobacco root to a 0.2-ml Eppendorf tube containing 10 μl double distilled water, 8 μl 10 × PCR Buffer (Mg–), and 2 μl of proteinase K (600 μg/ml) and frozen at –70°C for 30 min, then incubated at 65°C for 1 h and at 95°C for 10 min. After centrifugation at 12,000 rpm for 2 min, the DNA suspension was used for PCR amplification. Primers TW81 (5′-GTTTCCGTAGGTGAACCTGC-3′) and AB28 (5′-ATATGCTTAAGTTCAGCGGGT-3′) were used to amplify the rDNA internal transcribed spacer (ITS) region, and a PCR fragment of 1,030 bp was obtained. The sequence (GenBank Accession No. JX561139) showed 99% similarity to H. glycines strain Hg1-Ark1 (EF611124). Duplex PCR containing the universal primers D2A (5′-ACAAGTACCGTGAGGGAAAGTTG-3′), D3B (5′-TCGGAAGGAACCAGCTACTA-3′) and SCAR primers SCNFI (5′-GGACCCTGACCAAAAAGTTTCCGC-3′), SCNRI (5′-GGACCCTGACGAGTTATGGGCCCG-3′), obtained a 477-bp fragment, which is specific for SCN populations (2). Based on both morphological and molecular identification, the populations of cyst-forming nematodes on tobacco from Henan, China were confirmed as SCN. Pathogenicity tests were conducted on 30 each of 50-day-old tobacco and 5-day-old soybean plants (one plant per pot), respectively, by adding 2 ml of a suspension of 1,000 eggs and J2 of cysts collected from tobacco roots. After 35 days, 20 to 35 white females could be detected in each of the tobacco roots, and the yellowing symptom on almost all of tobacco plants was observed. Although infection on soybean plants was observed, the nematodes infected in roots was just 10 to 20 per pot, and they all stayed in the infective J2 stage. Except for one J3 until 48 dpi, no mature females could be found, and the nematode population could not reproduce on soybean tested. This suggests that the cyst nematode population from tobacco is a new pathotype of SCN. To our knowledge, this is the first report of SCN parasitized on tobacco in naturally infected fields, which is a potential threat to tobacco growth and should attract worldwide attention. References: (1) R. H. Mulvey. Can. J. Zool. 50:1277, 1972. (2) S. Ou et al. Nematology 10:397, 2008. (3) R. D. Riggs. In: Biology and Management of the Soybean Cyst Nematode, p. 107-114, 1992. (4) R. Venkatesh et al. Weed Technol. 14:156, 2000.

For the first time, plant pigments were detected in Roman frescoes. Indeed, only sporadic papers proved the application of natural hues in ancient paintings and none of them relative to Roman art. Therefore, eight differently coloured fragments of Julio-Claudian wall paintings, collected from Terme degli Stucchi Dipinti archaeological site (Rome, Italy), were subjected to GC–MS analysis, obtaining detailed chemical profiles. Vegetal dyes (ie. Indigotin, Neronine, Alizarin) or colourless metabolites ascribable to plant species (ie. Basella rubra, Sesanum radiatum, Lamium purpureum) were detected. Plant waxes, oils (ie. Brassicaceae) and resins (ie. Pinaceae) were found to be preferred as binders or protective coatings instead of animal glues (ie. collagen, egg). Several natural molecules, typically associated to plant organisms (ie. Lamiaceae and Citrus species), were also identified. These data suggest the predominant role of plant extracts in ancient art and increase the knowledge about organic materials of Roman frescoes, facilitating modern restorers’ activities.

The studies were caried out to determine the importance of some weeds occurrence in the flax monoculture the survival of Fusarium oxysporum f. sp. lini. It appearet that the roots of Veronica persica, Stellaria media, Lamium purpureum, Capsella bursa-pastoris and Sonchus arvensis were colonized by Fusarium oxysporum f. sp. lini. V. persica especially has, a profitable influence on the survival of F. oxysporum f. sp. lini. However. C. hursa-pastoris and S. arvensis stimulate the growth of fungi of the genera Trichoderma. which limites the occurrence of F. oxysporum f. sp. lini in the soil.

The purpose of this study is to offer the raw data for establishing the management and restoration plan by objective surveying and analysing the flora distributed in Seoak District, Gyeongju National Park, Korea. The flora summarized as 411 taxa including 92 families, 285 genera, 363 species, 2 subspecies, 41 varieties and 5 forms. The rare plants designated by Korea Forest Service were 2 taxa including Exochorda serratifolia and Potentilla discolor. The Korean endemic plants were 3 taxa including Philadelphus schrenkii, Lespedeza maritima and Weigela subsessilis. The specific plants by floristic region were 16 taxa including Asplenium sarelii, Pyrrosia petiolosa, Vitex negundo var. incisa and so forth. The target plants adaptable to climate change were 2 taxa including Lespedeza maritima and Carpesium macrocephalum, and the plants with approval for delivering oversea were 4 taxa including Exochorda serratifolia, Glycine soja, Lespedeza maritima and Weigela subsessilis. The naturalized plants were 51 taxa including Phytolacca americana, Viola papilionacea, Lamium purpureum and so forth. The invasive alien plants were 3 taxa including Ambrosia artemisiifolia, Aster pilosus and Lactuca scariola. NI(Naturalized Index) was 12.4% of all 411 taxa of surveyed flora in this study and UI(Urbanized Index) was 15.9% of all 321 taxa of naturalized plants in Korea. Potentilla discolor in rare plant, Philadelphus schrenkii in endemic plant and Dictamnus dasycarpus in specific plant were established the conservation plan. Whereas, invasive alien plants such as Ambrosia artemisiifolia, Aster pilosus and Lactuca scariola should be removed as soon as possible. The damaged sites in Seoak District were divided between wildfire area and farmland. To restore a forest fire site, we will have to apply a natural renewal and community planting. In case of farmland, we will have to do ecological planting using native species and constrcut a forest wetland.

A survey of twospotted spider mite, Tetranychus urticae Koch, hosts was conducted during the spring months of 2007, 2008, and 2009 in Mississippi. Uncultivated field borders that supported a diverse flora of herbaceous plants and adjacent in-field weeds were sampled from late-March through May for the presence of twospotted spider mite. Twospotted spider mite preference for each plant species was determined and ranked in a 0 - 3 scale. Henbit, Lamium amplexicaule L., was the most consistent and preferred host of twospotted spider mite in Mississippi. Carolina geranium, Geranium carolinianum L., cutleaf geranium, Geranium dissectum L., vetch, Vicia spp., volunteer soybean, Glycine max L., purple deadnettle, Lamium purpureum L., and spiny sowthistle, Sonchus asper (L.) Hill, were other frequently infested dicotyledonous species. Of the monocotyledonous species sampled, only rescuegrass, Bromus catharticus Vahl, john-songrass, Sorghum halepense (L.) Pers., and volunteer corn, Zea mays L., appeared t...

Background and aims The need is high to search for natural compounds with superior prebiotic, antioxidant and immunostimulatory properties for use in (food) applications. Raffinose Family Oligosaccharides (RFOs) show such properties. Moreover, they contribute to stress tolerance in plants acting as putative membrane stabilizers, antioxidants and signalling agents. Methods A large scale soluble carbohydrate screening was performed within the plant kingdom. An unknown compound accumulated to a high extent in early spring red deadnettle (Lamium purpureum) but not in other RFO plants. The compound was purified and its structure was unravelled with NMR. Organs and organ parts of red deadnettle were carefully dissected and analysed on soluble sugars. Phloem sap content was analysed by a common EDTA-based method. Key results Early spring red deadnettle stems and roots accumulate high concentrations of the reducing trisaccharide manninotriose (Galα1,6Galα1,6Glc), a derivative of the non-reducing RFO stachyose (Galα1,6Galα1,6Glcα1,2βFru). Detailed soluble carbohydrate analyses on dissected stem and leaf sections together with phloem sap analyses strongly suggest that stachyose is the main transport compound, but extensive hydrolysis of stachyose to manninotriose seems to occur along the transport path. Based on the specificities of the observed carbohydrate dynamics, the putative physiological roles of manninotriose in red deadnettle are discussed. Conclusions Here it is demonstrated for the first time that manninotriose is a novel and important player in the RFO metabolism of red dead deadnettle. It is proposed that manninotriose represents a temporal storage carbohydrate in early spring deadnettle, at the same time perhaps functioning as a membrane protector and/or as an antioxidant in the vicinity of membranes as recently suggested for other RFOs and fructans. This novel finding urges further research on this peculiar carbohydrate on a broader array of RFO accumulators. ispartof: Annals of Botany vol:111 issue:3 pages:385-393 ispartof: location:England status: published

The overall goal of the project was to test the hypothesis that Lamium amplexicaule and Lamium purpureum, weedy invasive species to North America, use phytotoxic allelochemicals in interplant competition. The chemical compositions of the essential oils from the aerial parts of L. amplexicaule and L. purpureum have been obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry. The essential oils and several essential oil components have been screened for phytotoxic activity on lettuce (Lactuca sativa) and perennial ryegrass (Lolium perenne) as well as nematocidal activity against Caenorhabditis elegans, brine shrimp (Artemia salina) lethality, and insecticidal activity against the red imported fire ant (Solenopsis invicta × richteri). L. amplexicaule essential oil was composed largely of α-pinene, β- pinene, 1-octen-3-ol, (E)-caryophyllene, and germacrene D, while L. purpureum oil was dominated by α-pinene, β-pinene, 1-octen-3-ol, β-elemene, and germacrene D. Neither essential oil exhibited notable phytotoxicity or lethality against nema-todes, brine shrimp, or fire ants. It is unlikely, therefore, that the allelopathy observed in these Lamium species is due to volatile phytochemical constituents.

The infection capacity of Potato virus Y (PVY, genus Potyvirus) for wild-living plants, commonly occurring as arable weeds in Europe and native to or naturalised in other continents, was evaluated. In total, 3,712 and 802 seedlings representing 21 weed species were aphid and sap-inoculated with PVY, respectively. Experimentally-inoculated plants of Erodium cicutarium, Geranium pusillum, Lactuca serriola and Lamium purpureum tested positive by ELISA, but they did not display any disease symptoms. The presence of PVY in selected plants of the four species was confirmed by back-inoculations to Nicotiana tabacum and by immunocapture-reverse transcription-PCR performed on samples taken from weed and/or tobacco plants. Natural PVY infection in plants of the four wild species collected in the potato-growing area was detected by ELISA and confirmed by back-inoculations to tobacco plants. This study is believed to be the first report of PVY infection in E. cicutarium, G. pusillum and L. purpureum. Moreover, our findings reveal for the first time PVY infection in L. serriola in central Europe.

Purple deadnettle is an obligate winter annual weed and an alternate host of soybean cyst nematode (SCN). Field experiments were conducted using microplots to determine (1) the effect of purple deadnettle planting date and (2) the effect of purple deadnettle removal time on SCN egg population density in continuous no-tillage soybean. A population change factor (PCF) to assess treatment effects on SCN population densities was calculated by dividing the SCN population density at each sampling time (Pf) by the initial population density before treatments were applied (Pi). In the planting date experiment, purple deadnettle seeded on October 3, 11, and 18 resulted in PCF values ranging from 7.28 to 11.41, which were three- to fivefold higher than the PCF values for the weed-free control or purple deadnettle seeded on September 6, 20, and 27. Self-thinning of purple deadnettle seeded in September may have resulted in higher levels of SCN mortality compared to later seeding dates. In the removal time e...

The interactions between herbivorous insects and their symbiotic micro-organisms can be influenced by the plant species on which the insects are reared, but the underlying mechanisms are not understood. Here, we identify plant nutrients, specifically amino acids, as a candidate factor affecting the impact of symbiotic bacteria on the performance of the phloem-feeding aphidAphis fabae.Aphis fabaegrew more slowly on the labiate plantLamium purpureumthan on an alternative host plantVicia faba, and the negative effect ofL. purpureumon aphid growth was consistently exacerbated by the bacterial secondary symbiontsRegiella insecticolaandHamiltonella defensa, which attained high densities inL. purpureum-reared aphids. The amino acid content of the phloem sap ofL. purpureumwas very low; andA. fabaeon chemically defined diets of low amino acid content also grew slowly and had elevated secondary symbiont densities. It is suggested that the phloem nutrient profile ofL. purpureumpromotes deleterious traits in the secondary symbionts and disturbs insect controls over bacterial abundance.

An experiment was conducted in growth chambers to determine the influence of cold temperature regimes, designed to simulate winter temperature conditions and spring recovery, on the interaction between purple deadnettle and soybean cyst nematode (SCN). The study was a factorial arrangement of treatments with five levels of temperature (20, 15, 10, 5, or 0 C), two levels of exposure time to the temperature (10 or 20 d), and two levels of recovery time at 20 C following exposure (0 or 20 d). In general, purple deadnettle shoot and root growth increased with temperature and time. The ability of purple deadnettle to recover from cold temperatures declined as the length of time that the plant was subjected to the cold temperature increased. SCN juveniles per gram of root at the conclusion of the temperature treatment declined as the temperature increased from 0 to 15 C, likely a result of continued purple deadnettle root growth and the inhibition of SCN hatch, growth, or development at those temperatures. SCN female, cyst, and egg production per gram of root generally increased with temperature and occurred under all temperature regimes. The results of this research indicate that, after hatching, SCN juveniles can survive a period of cold temperature inside the roots of a winter annual and continue development when transferred to warmer temperatures. Therefore, in a field environment, where fall or spring alone may not be sufficient for SCN to complete a reproductive cycle on a winter annual weed, the nematode may be able to reproduce by combining the fall and spring developmental periods.

Fifty-five soybean cyst nematode (SCN)–infested production fields across Indiana were surveyed in March 2004 to assess broadleaf winter weed prevalence. The most frequently occurring weeds were common chickweed (87%), speedwell (83%), buttercup (58%), and henbit (53%). Henbit and wild garlic were present at the highest average densities, both occurring at greater than 50 plants/m2. Based on relative abundance indices, common chickweed and henbit were the most prevalent winter weeds in this survey. As a composite, winter weed hosts of SCN were found in 93% of fields and occurred at an average density of 151 plants/m2. No correlation existed between weed density and SCN egg counts. Frequency, uniformity, density, and diversity indices for individual weed species were generally higher in the southern region of Indiana than in the north. Thus, the region of highest risk for SCN reproduction and population increase on winter weeds in Indiana appears to be in the southern part of the state.

Antioxidative effects of methanolic extracts from six wild European Lamiaceae species have been studied with the use of three in vitro assays. The ability of scavenging free radicals was measured by DPPH reduction spectrophotometric assay. The reducing potential towards transition metals was tested by phosphomolybdenum method and the inhibition of lipid oxidation was tested by Fe/ascorbate system with photometric TBARS detection. All studied herbs exposed strong antioxidant capability, but the results were different for each species depending on the applied test. In DPPH scavenging the order from strongest to the weakest was: Leonurus cardiaca, Lamium album, Marrubium vulgare, Stachys officinalis, Lamium purpureum, Galeopsis speciosa. With phosphomolybdenum method the extract of S. officinalis was the strongest in both 40 degrees Celsius and 90 degrees Celsius but other species acted differently in both temperatures. In lipid peroxidation assay, the maximum inhibition of 78% was reached by S. officinalis and M. vulgare, whereas for both Lamium sp. and L. cardiaca slightly exceeded 70% and for G. speciosa reached 65%. The observed differences indicate the complexity of involved mechanisms and support the necessity of combining several assays in studying the antioxidant potential of medicinal plants.

The essential oils and the volatiles emitted in vivo by flowers, leaves and bracts of Lamium purpureum, L. hybridum, L. bifidum, L. amplexicaule (Lamiaceae) were analyzed by GC-MS and SPME, respectively. All the essential oils were characterized by their high contents of germacrene D. In L. purpureum (35.4%), L. hybridum (39.0%) and L. bifidum (34.9%), it was the main compound, while in L. amplexicaule (28.9%), the main constituent was trans-chrysanthenyl acetate (41.1%). The SPME analyses showed a pattern typical of volatiles for both the different species and the single plant parts analyzed.

SUMMARY The black-bean aphid Aphis fabae bears populations of coccoid symbiotic bacteria Buchnera spp. at 2.0–3.2×107cellsmg−1aphidmass and rod-shaped secondary symbionts of uncertain taxonomic affiliation at 0.1–0.6×107cellsmg−1aphidmass. Buchnera provides essential amino acids, supplementing the poor supply in the aphid diet of plant phloem sap. Comparison of the performance of A. fabae containing and experimentally deprived of their bacteria showed that the bacteria caused increased larval mass of aphids reared on Chenopodium album and Papaver dubium plants, but not when reared on Lamium purpureum. In the aphids reared on L. purpureum, the density of the bacteria, especially the secondary symbionts, was significantly elevated, and bacterial-mediated production of the essential amino acid threonine was reduced, even though the essential amino acid content of phloem exudates from L. purpureum had a low threonine content. It is proposed that the shortfall in threonine, possibly compounded by the high density of secondary symbionts, may contribute to the poor performance of the aphids on L. purpureum. This study offers the first evidence to suggest plant-mediated interference with the nutritional function of symbiotic bacteria in any phytophagous insect.

In greenhouse experiments, Ohio accessions of 22 weed species representing 13 dicot families were screened as alternative hosts of soybean cyst nematode (SCN, Heterodera glycines). Purple deadnettle (Lamium purpureum), henbit (Lamium amplexicaule), field pennycress (Thlaspi arvense), shepherd's-purse (Capsella bursa-pastoris), and a susceptible soybean (Glycine max) cultivar produced SCN population densities of 510, 155, 73, 1, and 366 cysts/450 cm3 soil, respectively, 5 wk after inoculation with eggs from a race 3 SCN population. Purple deadnettle was also a strong host of race 1 SCN and a weak host of race 6 SCN. Average numbers of eggs/cyst among race 3 hosts were highest in purple deadnettle (357), followed by soybean (292), field pennycress (266), henbit (122), and shepherd's-purse (none detected). To our knowledge, henbit is the only SCN host identified here that has been previously identified as a host. The weeds identified as SCN hosts in this study have a winter annual life cycle in Ohi...

Two species of leaf beetles, Chrysolina tundralis and Ch. roddi, were found in the “Galich’ya Gora” Nature Reserve (the middle part of European Russia), 1200 and 700 km, respectively, from the main part of the ranges of these species. Adults and larvae of Ch. tundralis feed on Lamium purpureum, those of Ch. roddi feed on Seseli intermedia there. Diagnostic characters of the adults of both species are reported.

Summary. As Arion lusitanicus has been observed in high densities in wildflower strips, the palatability of the foliage of 78 species of sown and naturally occurring plants found in such strips was investigated. In the laboratory, the slugs were offered a surplus of fresh, mature leaves and, after 16 h, a consumption index was calculated to rank the plants according to their palatability to the slugs. Arion lusitanicus showed clear preferences for particular plant species, but more than two thirds of all plants investigated were scarcely eaten. Brassica napus was most eaten, followed by Papaver rhoeas, Capsella bursa-pastoris and Lamium purpureum. Overall, A. lusitanicus preferred sown species to naturally occurring ones and preferred annuals to perennials.

Summary: Resume: Zusammenfassung The joint action of mixtures of the sulfonylurea herbicides chlorsulfuron, metsulfuron and tribenuron and MCPA as a dimethylamine salt was assessed on Stellaria media L. and Lamium purpureum L. Two statistical analyses, and appropriate experimental designs, were used—the additive dose model (ADM) and the principle of parallel dose-response curves. The ADM analyses revealed that mixtures of the sulfony-lureas and MCPA were less potent than expected on Stellaria while the parallel-line assay analyses showed that activity of the sulfonylurea herbicides on Stellaria and Lamium was reduced in mixtures with MCPA. The antagonism was found to be dependent on the ratio of the two herbicides. Activity decreased with increasing MCPA ratios in the mixtures. Sequential spraying and selective placement of droplets revealed that MCPA only antagonized the sulfonylureas when the herbicides were in physical contact with each other. The benefits of applying both statistical methods when studying the joint action of two herbicides both possessing activity on the test plants are discussed. Action de melanges d'herbicides sulfonylurees et de MCPA L'action de melanges des herbicides sulfonylurees chlorsulfuron, metsulfuron et tribenuron avec le MCPA formule en sel de dimethylamine, a ete etudiee sur Stellaria media L. et Lamium purpureum L. Deux analyses statistiques asso-ciees a deux systemes experimentaux appropries ont ete utilises: le modele a doses additives (ADM) et le principe du parallelisme des cour-bes dose-effet. Les analyses ADM ont montre que les melanges de sulfonylurees et de MCPA ont ete rnoins efficaces qu'attendu sur Stellaria. Les analyses en courbes paralleles ont montre que 1'activite des herbicides sulfonylurees sur Stellaria et Lamium etait reduite dans des melanges avec le MCPA.L'antagonisme dependait du rapport entre les doses des deux herbicides, 1'activite decroissant avec 1'augmentation du taux de MCPA. Des traitements sequentiels et des depots localises de gouttelettes ont montre que le MCPA n'etait an-tagoniste des sulfonylurees que lorsque les herbicides etaient physiquement en contact. L'interet est discute, d'utiliser les deux methodes statistiques de concert pour etudier les interactions entre deux herbicides actifs sur les plantes test. Gemeinsame Wirkung von Sulfonylharnstoff-Herbiziden und MCPA Die Wirksamkeit von Mischungen der Sulfonyl-hamstoff-Herbizide Chlorsulfuron, Metsulfuron und Tribenuron mil MCPA als Dimethylamin-salz wurde an Stellaria media L. und Lamium purpureum L. bestimmt. Die Versuche wurden so angelegt, um 2 statistische Analysen anzuwen-den: das Additiv-Dosis-Modell (ADM) und das Prinzip paralleler Dosis-Wirkungs-Kurven. Die ADM-Analyse ergab, das diese Mischungen gegenuber Stellaria weniger wirksam als erwartet waren, wahrend die Parallel-Analyse zeigte, das die Wirksamkeit der Sulfonylharnstoff-Herbiz-ide in Mischungen mil MCPA gegeniiber den beiden Arten herabgesetzt war. Es ergab sich, das der Antagonismus vom Verhaltnis der Mischungspartner abhangt. Die Wirkung nahm mit steigenden MCPA-Anteilen in den Mischungen ab. In Spritzfolgen und bei separater Applikation zeigte sich, das MCPA nur dann gegenuber Sulfonylharnstoffe antagonistisch wirkte, wenn sich die Herbizide vermischten. Die Vorzuge der Anwendung der beiden statistischen Methoden zur Untersuchung des gemeinsamen Effektes von 2 Herbiziden ahnlicher Wirkung werden diskutiert.

Automatic identification of 10 weed species in digital images using Fourier descriptors and shape parameters Plant species discrimination in mixed plant communities has recently become possible using transforms and shape parameters to classify digital images. In the present study image analysis techniques were used to identify weeds commonly found in winter cereal fields. Those species included Veronica hedenfolia L., Thlaspi arvense Beauv., Alopecurus myosuroides L., Apera spica-venti L., Poa annua L., Stellaria media L., Capsella bursa-pastoris L., Lamium purpureum L., Matricaria chamomilla L. and Galium aparine L. Images of several growth stages of these weeds were photographed using a Still Videokamera, binarified, the shape extracted and then Fourier descriptors and shape parameter were calculated for each weed. Classified digital images of each species were stored on the computer. A separate set of photographic images of these 10 weeds were used to test the ability of the classified images for plant identification. The average rate of correct identification was 81.9 % ranging from 41.6 % to 100 %. Zusammenfassung In dieser Arbeit wurde ein Verfahren zur Erkennung von zehn Unkrautarten im Wintergetreidebau entwickelt. Diese zehn Spezies sind: Veronica hederifolia L., Thlaspi arvense Beauv., Alopecurus myosuroides Huds., Apera spica-venti L., Poa annua L., Stellaria media L., Capsella bursa-pastoris L., Lamium purpureum L., Matricaria chamomilla L. und Galium aparine L. Die Unkrauter wurden mit einer elektronischen CCD-Still-Videokamera im Herbst 1991 aufgenommen. Anschliesend wurde die ausere Kontur der Unkrauter im Binarbild extrahiert und Fourierdeskriptoren sowie Formparameter berechnet und im Speicher des Rechners abgelegt. Eine Wissensbasis aus einigen reprasentativen Individuen jeder Art wurde aufgebaut. Die Wiedererkennungsstudie erfolgte mit anderen Individuen der gleichen Spezies. Folgende Ergebnisse lassen sich zusammenfassen. 1. Die durchschnittliche Wiedererkennungsrate der untersuchten Unkrautspezies betrug 81,9 % und variierte von 41,6 % fur Galium aparine bis 100 % fur Veronica hederifolia. 2. Die Zeit der Wiedererkennung fur ein Unkraut betrug mit einem 10-MHz-Rechner ohne Coprozessor je nach Komplexitat der auseren Kontur und der Grose der Wissensbasis 30 bis 39 Sekunden.

РЕЗЮМЕПосредством иммуноферментного метода двойного антитело-сендвича ЕЛИЗА (ДАСЕЛИЗА) и тестов (Германия) установлены новыехозяева для некоторых вирусов свеклы. Сорняк Xanthium italicum (Moretti) - хозяин вируса некротического пожелтения жилок свеклы (beet necrotic yellow vein virus (BNYVV). Raphanus raphanistrim L. -хозяин вируса мозаики свеклы - beet mosaic virus (ВМV), вируса желтухи свеклы - beet yellow virus (BYV), вируса мягкой желтухи свеклы - beet mild yellowing virus (BMYV), вируса табачной мозаики - tobacco mosaic virus (TMV). Сорняк Lamium purpureum L. является хозяином BYV и TMV. Сорняки Amaranthus retroflexus L., Convolvulus arvensis L., Galinsoga parviflora Cav.,Solanum nigrum L., Raphanus raphanistrum L. и Xanthium italicum (Moretti) - хозяева ТМV. BMYV в листьях сахарной свеклы и листьях Raphanus raphanustrum L. Обнаружен в Болгарии впервые.

Five new phenylethanoid glycosides, lamiusides A (1), B (2), C (3), D (4) and E (5), were isolated from the whole plants of Lamium purpureum L. (Labiatae) together with seven known compounds (6-12). On the basis of chemical and spectral analyses, the structures of the new compounds were elucidated to be 2-(3,4-dihydroxyphenyl)ethyl-O-beta-D-galactopyranosyl-(1--2)-alpha-L-rhamnopyranosyl-(1--3)-(4-O-trans-caffeoyl)-beta-D-glucopyranoside (1), 2-(3,4-dihydroxyphenyl)ethyl-O-beta-D-galactopyranosyl-(1--2)-alpha-L-rhamnopyranosyl-(1--3)-(4-O-trans-feruloyl)-beta-D-glucopyranoside (2), 2-(3,4-dihydroxyphenyl)ethyl-O-beta-D-galactopyranosyl-(1--2)-alpha-L-rhamnopyranosyl-(1--3)-(6-O-trans-caffeoyl)-beta-D-glucopyranoside (3), 2-(3,4-dihydroxyphenyl)-R,S-methoxy-ethyl-O-beta-D-galactopyranosyl-(1--2)-alpha-L-rhamnopyranosyl-(1--3)-(4-O-trans-caffeoyl)-beta-D-glucopyranoside (4) and 2-(3-hydroxy-4-methoxyphenyl)ethyl-O-alpha-L-rhamnopyranosyl-(1--3)-beta-D-glucopyranosyl-(1--6)-(4-O-cis-feruloyl)-beta-D-glucopyranoside (5). In addition, the radical-scavenging activities of compounds 1-4 on 1,1-diphenyl-2-picrylhydrazyl radical were examined.

The experiments of Haberlandt with isolated leaf cells of Lamium purpureum L., started in 1898 and published in 1902, laid the foundations of in vitro culture in higher plants. Based on the cell theory of Schwann and Schleiden, he considered every cell as an elementary organism and was convinced of the totipotency of even differentiated cells. Haberlandt and his successors achieved a limited survival and an extension growth of isolated cells but no real culture, meaning no division growth, due to the lack of favourable media at that time.

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Undifferentiated plant cells may be used in simplified systems for studying the interactions be- tween plants and fungi. We used plant calli for inves- tigating the interactions between three endophytic fungi (Coniothyrium palmarum, Geniculosporium sp. and Phomopsis sp.) and their host and nonhost plants (Lamium purpureum and Teucrium scorodonia), show- ing that growth of these endophytes was specifically enhanced by calli of the host. Substance(s) secreted by the host calli were responsible for this growth re- sponse. The endophytes also secreted metabolites into the medium. These were toxic to the plant calli, irrespective of whether it was a host or nonhost in- teraction. Further tests demonstrated the nonspecific herbicidal nature of these substances.

Summary A survey of grass weeds of cereals in central southern England made in 1981 was repeated in 1982 between 28 June and 23 July. Dicotyledonous weeds were also assessed in 1982. A total of 1021 fields were surveyed, 702 in winter wheat. 198 in winter barley and 121 in spring barley. A total of twenty-four grass weeds were found and their levels of infestation were scored. The most frequently found grass weeds were the same as in 1981. In all cereals combined, these were Elymus (Agropyron) repens in 35% of fields, Avena fatua in 32%, Alopecurus myosuroides in 26% and Poa trivialis in 24%. Sixty-three species of dicotyledonous weeds were recorded and of these, eighteen species occurred in 2% or more of fields. The eight most frequent were Viola arvensis, Galium aparine, Stellaria media, Myosotis arvensis, Polygonum aviculare, Convolvulus arvensis, Bilderdykia (Polygonum) convolvulus and Lamium purpureum. Most species were fairly uniform in distribution, but Galium aparine, Convolvulus arvensis and Cirsium arvense were most frequent in the east while Viola arvensis was least frequent there. The cereals varied in weediness, 32% of winter barley, 23% of spring barley and only 7% of winter wheat fields had no weeds recorded. Rasuma Deuxieme evaluation des mauvaises herbes de cultures cerealieres dans la region centrale du sud de l'Angleterre Les adventices graminees des cultures cereatieres de la region centrale du sud d'Angleterre ont eteevaluees en 1981 et de nouveau entre le 28 juin et le 23 juillet 1982. l'evaluation a porte sur 1021 champs, dont 702 en culture de ble. 198 en culture d'orged'hiver et 121 en culture d'orge d'ete. On a trouve en tout vingt-quatre especes de graminees adventices; le niveau de ces infestations a ete enregistre. Les especes les plus frequentes etaient les memes qu'en 1981, a savoir, dans toutes les cultures cerealieres: Elymus (Agropyron) repens dans 35% des champs, Avena fatua dans 32%, Alopecurus myosuroides dans 26% et Poa trivialis dans 24%. Soixante-trois especes d'adventices dicotyledonees ont ete enregistrees, dont dix-huit etaient presentes dans plus de 2% des champs. Les huit especes les plus frequentes etaient: Viola arvensis, Galium aparine, Stellaria media, Myosotis arvensis, Polygonum aviculare, Bilderdykia (Polygonum) convolvulus, Convolvulus arvensis et Lamium purpureum. Pour la plupart des especes la distribution etait a peu pres uniforme mais Galium aparine, Convolvulus arvensis et Cirsium arvense se sont revelees les plus frequentes dans l'est de la region, tandis que Viola arvensis y etait la moins frequente. Le niveau d'infestation variait selon les differentes especes cerealieres; 32% des cultures d'orge d'hiver, 23% des cultures d'orge des cultures d'orge d'ete et seulement 7% des cultures de ble d'hiver se sont trouvees indemnes d'adventices. Zusammenfassung Eine zweite Schatzung der Getreideunkrauter in Mittelsudengland Die 1981 ausgefuhrte Schatzung der Ungraser in Getreidekulturen Mittelsudenglands wurde 1982 zwischen 28 Juni und 23 Juli wiederholt. Auch dikotyle Unkrauter wurden 1982 abgeschatzt. Ein Gesamtbetrag von 1021 Feldern wurde ausgewertet: 702 Winterweizenfelder, 198 Wintergerstfelder und 121 Sommergerstfelder. Im Gesamten wurden 24 Ungrasarten gefunden und ihre Besatzungsniveaus Geschatzt. Die haufigst vorkommenden Ungraser waren dieselben wie in 1981. Diese waren in allen Getreidekulturen zusammen: Elymus (Agropyron) repens in 35% der Felder, Avena fatua in 32%, Alopecurus myosuroides in 26% und Poa trivialis in 24%. Es wurden 63 dikotyle Unkrauter verzeichnet, wovon 18 Arten in wenigstens 2% der Felder vorkamen. Die acht haufigst gefundenen Arten waren Viola arvensis. Galium aparine, Stellaria media, Myosotis arvensis, Polygonum aviculare. Convolvulus arvensis. Biderdykia (Polygonum) convolvulus und Lamium purpureum. Die meisten Arten zeigten eine ziemlich gleichformige Verteilung aber Galium aparine, Convolvulus arvensis und Cirsuim arvense waren am haufigsten im Ostteil des Gebietes. Wahrend Viola arvensis dort am seltensten vorkam. Die Unkrautbesatzung war in den Getreidearten verschieden: in 32% der Wintergerst- 23% der Sommergerst- und nur 7% der Winterweizenfeldern wurden keine Un-krauter verzeichnet.

The life history of the burrower bug Sehirus cinctus cinctus (Palisot de Beauvois) was studied in Illinois, and the immature stages were described. The bug was also reared from egg to adult under laboratory conditions, and precopulatory behavior, and maternal care of eggs and young instars, were observed. The female occasionally provided her 1st instars with the seeds. Adults of this univoltine subspecies overwinter in soil associated with their mint host plant, Lamium purpureum Linn. They become active in early April and reproduce shortly thereafter. The female lays her eggs in a loose cluster in a chamber in the soil and guards them during incubation. The 1st instars are highly gregarious and often cluster around and on the female. Older nymphs are also gregarious but decreasingly so as they mature, and usually leave the chamber during the second stadium. Nymphs and adults fed on seeds of L. purpureum. On seeds of L. purpureum, and at 23.9 ± 1.1°C and 16L:8D, total developmental time averaged 53.21 days. The incubation period averaged 10.21 days. Durations of the five nymphal stadia averaged 5.29, 6.26, 6.53, 9.70, and 15.22 days, respectively.

Summary Fresh seeds of Lamium purpureum L. were dormant at maturity, and when buried and exposed to natural seasonal temperature changes they exhibited an annual dormancy/non-dormancy cycle. During burial in summer, fresh seeds and those that had been buried for 1 year afterripened and thus were non-dormant by September and October; light was required for germination. During autumn and winter seeds re-entered dormancy, and during the following summer they became non-dormant again. Dormant seeds afterripened when buried and stored over a range of temperatures, becoming conditionally dormant at low (5, 15/6°C) and non-dormant at high (20/10, 25/15, 30/15 and 35/20°C) temperatures. Conditionally dormant seeds germinated to high percentages at 5, 15/6 and 20/10°C, while non-dormant seeds germinated to high percentages additionally at 25/15, 30/15 and 35/20°C. Low temperatures caused non-dormant seeds to re-enter dormancy, while high temperatures caused a sharp decline in germination only at 30/15 and 5°C. The temperature responses of L. purpureum seeds are compared to those of L. amplexicaule L.

SUMMARY Seeds or fruits of 10 species of annual weeds were collected in each of 3 years and mixed with the top 7 · 5 cm of sterilised soil (confined in cylinders sunk in the ground outdoors and cultivated three times yearly. The numbers of seedlings emerging were recorded for 5 yr and the numbers of viable seeds remaining then determined. Emergence of Anagallis arvensis, Anchusa arvensis, Chaenorrhinum minus and Euphorbia peplus was mainly in spring; Lamium amplexicaule and Myosotis arvensis also had a spring peak but emergence continued in summer and autumn. Seedlings of Aphanes arvensis appeared almost entirely in autumn and those of Lamium purpureum between May and October. Veronica arvensis had spring and autumn peaks, while Fumaria densiflora showed no definite pattern. Except for Anagallis arvensis and F. densiflora, in which there was apparent innate dormancy due to the seed coat, most seedlings appeared in the first year with a decrease, usually exponential, from year to year. This was most rapid in C. minus and E. peplus, of which few viable seeds remained after 5 yr. Seed survival for the other species ranged from 2·6% of those sown for Anchusa arvensis to 14·8% for F. densiflora.