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In vivo labelling of Anagallis arvensis L. cells with green fluorescent protein
Marcin ?ukaszewicz,Dorota Kwiatkowska
Acta Societatis Botanicorum Poloniae , 2000, DOI: 10.5586/asbp.2000.010
Abstract: A few methods only enable to follow the fate of plant cells in vivo. One of the most promising is using the Green Fluorescent Protein (GFP). In our preliminary study we set up the experimental system enabling labelling of Anagallis arvensis cells with this marker. We prepared an expression plasmid containing red-shifted gfp with optimised translation start site context, under the control of CaMV 35S transcription promoter. The construct was introduced into A. arvensis cells by particle bombardment. We developed two methods of material preparation for this transformation: in vitro cultured stem internodes with regenerating adventitious shoots (the earliest stages of regeneration); and shoot tips with temporarily exposed apices. The reflected light fluorescence microscope Olympus with the set of filters U-MNB designed for fluorescein detection enables the observation of GFP fluorescence. Both ordinary epidermal cells and stomata guard cells were transformed. Their fluorescence was observed for up to 14 days. Artefacts (autofluorescence of glandular trichomes and faint green glowing of meristematic tissue) could be overcome by the optimisation of the filter set.
Intraspecific variation of phyllotaxis stability in Anagallis arvensis
Dorota Kwiatkowska
Acta Societatis Botanicorum Poloniae , 1997, DOI: 10.5586/asbp.1997.031
Abstract: Qualitative transformations of phyllotaxis in Anagallis arvensis occur typically during the generative phase of development. In the vegetative phase phyllotaxis usually does not change. An exception to this rule is one peculiar population of Anagallis arvensis, belonging to a pink-flowered form carnea, in which phyllotaxis often transforms in both the generative and vegetative phase of development. The presence of a relatively large number of vegetative transitions, virtually absent in two control red-flowered populations of form arvensis, is accompanied also by the higher frequency of generative transitions. This might be a result of a genetically determined instability of shoot apex geometry. It has been proved experimentally that changing conditions of growth affect the transition frequencies and the time lapse from the beginning of either the vegetative or generative phase to the transition (measured in plastochrons). A comparison of two types of transitions shows that divergence changes are less abrupt in vegetative transitions. The differences between the two types also pertain to the vertical spacing of leaves and to the pattern formed by leaf bases and wings on the stem surface in the transition zone.
Ontogenetic changes of phyllotaxis in Anagallis arvensis L.
Dorota Kwiatkowska
Acta Societatis Botanicorum Poloniae , 1995, DOI: 10.5586/asbp.1995.041
Abstract: During the ontogeny of Anagallis spontaneous changes of phyllotaxis appear in a regular sequence. The initial decussate pattern is followed by spiral Fibonacci phyllotaxis, this in turn, by a trimerous pattern, and finally Lucas spiral phyllotaxis is formed. In the course of the first and most common phyllotactic transition, from the decussate to spiral Fibonacci pattern, changes in primordia arrangement occur only within a limited sector of the apex circumference. In the complementary sector, primordia emerge as if the decussate phyllotaxis continued. It is likely that similar circumferential discontinuity accounts for further transitions. The common ontogenetic sequence of patterns in Anagallis is such that, theoretically, each transition requires minimal changes in shoot apex geometry. Although the meristem in Anagallis is able to produce primordia either in whorls or spirally, the elongated shoots of this plant seem to have leaves exclusively in whorls. It appeared that in shoots with an initially spiral pattern, leaves can be clustered in pseudo-whorls due to the uneven internode elongation. Pseudowhorls are composed usually of three (Fibonacci) or four (Lucas) leaves of successive nodes. The number of leaves in a pseudo-whorl equals the number of leaves positioned on one revolution of the ontogenetic helix, which is different in these two spiral patterns. In shoot apices with whorled phyllotaxis, the leaf and flower primordia of a whorl are of different size. On elongated shoots, flower buds emerging in the axils of leaves of one whorl also differ in size.
A new way of dissemination in Anagallis arvensis L. (Primulaceae)
Jacek Drobnik,Barbara Bacler
Acta Societatis Botanicorum Poloniae , 2007, DOI: 10.5586/asbp.2007.028
Abstract: Anagallis arvensis L. fruits are globose pyxides. They contain a unique globose columella with 20-30 seeds on its surface. In ripe, open fruits the ball-shaped columella detaches easily and becomes a unique diaspore, which can roll on the ground. This way of dissemination has not been described so far neither in Anagallis nor in other Primulaceae.
On the Delimitation of Anagallis arvensis L. (Primulaceae) 1. Evidence Based on Macromorphological Characters, Palynological Features and Karyological Studies
Abdel Moneim,I. I. Aboel Atta,Azza A. Shehata
Pakistan Journal of Biological Sciences , 2003,
Abstract: Macromorphological characters, palynological features and karyological criteria were investigated in two taxa of Anagallis arvensis growing in Egypt. Significant variations were recorded in palynological features in the two taxa, thus favouring the view held by some authors regarding the two taxa as distinct subspecies of Anagallis arvensis.
Allelopathic Potential of Anagallis arvensis L. : A Cosmopolitan Weed  [PDF]
Zenab Rebaz,S. Shahid Shaukat,Imran A. Siddiqui
Pakistan Journal of Biological Sciences , 2001,
Abstract: Effect of Anagallis arvensis L. on seed germination and early seedling growth of six test species was examined. Aqueous extract of A. arvensis inhibited germination, root and shoot growth of all the six test species. The species exhibited differential response to the extract. Germination was reduced by the shoot extract in the order: pearl millet > mustard > carrot > turnip > wheat = corn. Decaying A. arvensis in sandly-loam soil at 5, 10 and 20 g / kg soil substantially inhibited germination and seedling growth of pearl millet at all the dosages. Bioassay of the extract of A. arvensis revealed two zones of inhibition at Rf values 0.8-0.9 and 0.9-1.0. Chromatography for the phenolics revealed the presence of three phenolic acids: salicylic acid, cinnamic acid and caffeic acid.
Ontogenetic changes in the shoot primary vasculature of Anagallis arvensis L.
Dorota Kwiatkowska
Acta Societatis Botanicorum Poloniae , 1995, DOI: 10.5586/asbp.1995.028
Abstract: Ontogenetic changes in the primary vasculature of Anagallis shoots are strictly related to phyllotaxis. During the ontogeny of Anagallis, whorled and spiral phyllotactic patterns appear alternately in a regular sequence. The initial decussate phyllotaxis is transformed into the spiral Fibonacci, and then further into trimerous pattern. This in turn may change into the spiral Lucas phyllotaxis. Sporadically the immediate transition from the decussate to trimerous phyllotaxis takes place. The vascular system in Anagallis is always closed, despite that both whorled and spiral phyllotaxes are present. Also the number of vascular traces diverging to the leaf is constant. In the course of a single phyllotactic transition, there is an increase in the number of vascular sympodia and in the number of leaf traces present in the vascular cylinder. Usually only one single sympodium and one or two traces are added to the system. The immediate addition of two sympodia occurs only during infrequent transition from the decussate to trimerous pattern. The increase in the number of sympodia is most often simultaneous with the phyllotactic transition, however, when the trimerous pattern is transformed into the spiral Lucas, the increase is delayed, sometimes for as much as ten plastochrons. In shoots with changing phyllotaxis, a sector within the vascular cylinder can be distinguished, in which the leaf traces are arranged as if the previous phyllotactic pattern continued, whereas rearrangement of traces takes place at the same level but in the complementary sector. This is in agreement with the concept of discontinuous circumferential changes in the shoot apex being responsible for qualitative transformations of phyllotaxis.
Phyllotaxis of vegetative shoots of Anagallis arvensis L. treated in vitro with 6-benzylaminopurine
Dorota Kwiatkowska,Krystyna Kromer
Acta Societatis Botanicorum Poloniae , 1999, DOI: 10.5586/asbp.1999.024
Abstract: Application of 6-benzylaminopurine (BA), a synthetic cytokinin, to the growth medium in vitro stimulates the formation of adventitious shoots on stem explants of Anagallis arvensis. They regenerate from dedifferentiating epidermal cells of stem internodes. The process starts from periclinal and anticlinal divisions in a few of neighbouring cells. The amount of adven-titious shoots increases with an increasing BA concentration. The BA treatment also affects phyllotaxis, but only of adventitious shoots, and not of normal lateral shoots developing in leaf axils. Leaf arrangement on adventitious shoots is always variable, even on the control medium. Generally, patterns observed in case of in vitro shoots do not differ from those reported earlier for intact A. arvensis plants. BA treatment also leads to the teratologic development, i.e. fasciation and the formation of abnormally shaped leaves, but again in adventitious rather than in normally developing shoots. We postulate that the variability of phyllotaxis characteristic for adventitious shoots and their responce to BA treatment, result from the fact that their apical meristems develop de novo from initially unorganised meristematic centres, whereas meristems of normally developing lateral shoots are well organised from the time of their initiation.
Plant bioassays to assess toxicity of textile sludge compost
Araújo, Ademir Sérgio Ferreira;Monteiro, Regina Teresa Rosim;
Scientia Agricola , 2005, DOI: 10.1590/S0103-90162005000300013
Abstract: composting of industrial wastes is increasing because of recycling requirements set on organic wastes. the evaluation of toxicity of these wastes by biological testing is therefore extremely important for screening the suitability of waste for land application. the toxicity of a textile sludge compost was investigated using seed germination and plant growth bioassays using soybean and wheat. compost samples were mixed with water (seed germination bioassay) or nutrient solution (plant growth bioassay) at concentrations of 0, 19, 38, 76 and 152 g l-1. no negative effects were observed after five days of compost water-extract in relation to soybean and wheat seed germination. after fifteen days, under a hydroponics system, plant growth had harmful effects of the compost at concentrations above 38 g l-1. textile sludge compost presented great phytotoxicity under hydroponics condition and the soybean and wheat were sensitive for evaluation of organic wastes in plant growth bioassays.
Plant bioassays to assess toxicity of textile sludge compost  [cached]
Araújo Ademir Sérgio Ferreira,Monteiro Regina Teresa Rosim
Scientia Agricola , 2005,
Abstract: Composting of industrial wastes is increasing because of recycling requirements set on organic wastes. The evaluation of toxicity of these wastes by biological testing is therefore extremely important for screening the suitability of waste for land application. The toxicity of a textile sludge compost was investigated using seed germination and plant growth bioassays using soybean and wheat. Compost samples were mixed with water (seed germination bioassay) or nutrient solution (plant growth bioassay) at concentrations of 0, 19, 38, 76 and 152 g L-1. No negative effects were observed after five days of compost water-extract in relation to soybean and wheat seed germination. After fifteen days, under a hydroponics system, plant growth had harmful effects of the compost at concentrations above 38 g L-1. Textile sludge compost presented great phytotoxicity under hydroponics condition and the soybean and wheat were sensitive for evaluation of organic wastes in plant growth bioassays.
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