scholarly journals Ruderal vegetation in Serbia - diversity and floristic composition

2021 ◽  
Vol 45 (2) ◽  
pp. 251-261
Author(s):  
Milena Tabasevic ◽  
Dmitar Lakusic ◽  
Nevena Kuzmanovic ◽  
Snezana Vukojicic ◽  
Milan Glisic ◽  
...  

This study represents the first data gathering and analysis of the floristic composition of ruderal vegetation in Serbia, published over the last 70 years. The dataset included 748 relev?s of ruderal communities and a total of 716 plant species and subspecies. The study showed that the most abundant were widespread taxa, especially taxa of the Eurasian area type, while alien species accounted for a relatively small proportion of the ruderal flora (about 10%). Therophytes and hemicryptophytes were most abundant in the life form spectra. Five vegetation groups were identified, corresponding to the following vegetation classes: Bidentetea, Sisymbrietea, Digitario sanguinalis-Eragrostietea minoris, Artemisietea vulgaris and Polygono-Poetea annuae. The analysis of similarity showed that there are small floristic differences between particular vegetation groups. The determined diagnostic species for the vegetation groups were compared with those of the corresponding anthropogenic vegetation classes, and a high degree of similarity was found for all but one group. The most frequent taxa in all five groups were Polygonum aviculare, Convolvulus arvensis, Plantago major subsp. major and Chenopodium album.

Weed Science ◽  
1981 ◽  
Vol 29 (5) ◽  
pp. 521-524 ◽  
Author(s):  
O. P. Kataria ◽  
Vijay Kumar

Control of littleseed canarygrass (Phalaris minor Retz.), wild oat (Avena fatua L.), common lambsquarters (Chenopodium album L.), and field bindweed (Convolvulus arvensis L.) in dwarf wheat (Triticum aestivum L.) fields was studied with five herbicides and hand weeding. Terbutryn [2-(tert-butylamino)-4-(ethylamino)-6-(methylthio)-s-triazine] and 1-benzthiazol-2-yl-1,3-dimethylurea controlled the weeds more effectively than did two hand weedings. Diuron [3-(3,4-dichlorophenyl)-1,1-dimethylurea], nitrofen (2,4-dichlorophenyl p-nitrophenyl ether), and dichlormate (3,4-dichlorobenzyl methylcarbamate), proved only partially effective against weeds, and were therefore significantly inferior to two hand weedings. Spikes per meter of row length and test weight of wheat were increased significantly by 1-benzthiazol-2-yl-1,3-dimethylurea (1.5 to 2 kg/ha), terbutryn (0.5 kg/ha), and two hand weedings over the yields of the weedy check. The 1-benzthiazol-2-yl-1,3-dimethylurea showed a high degree of selectivity in the wheat crop at 2 kg/ha and increased yields to those of weed-free plots. Terbutryn was almost as effective as 1-benzthiazol-2-yl-1,3-dimethylurea, which increased the wheat yields over those of the weedy check by 19.8 and 42.4% during the 1974/75 and 1975/76 seasons, respectively. Tolerance of dwarf wheat to terbutryn at 0.75 kg/ha was variable, resulting in significant decreases in yield components and grain yield. Dry-matter yield of wheat was negatively correlated with the dry matter production of weeds.


2012 ◽  
Vol 20 (2) ◽  
pp. 71-83 ◽  
Author(s):  
Jerzy Lisek

Abstract Research on synanthropic flora was conducted in the orchards of central Poland (near Skierniewice, Łowicz and Grójec). In the 2007-2010 time period, 390 phytosociological releves were taken, which included herbicide fallow under trees, swarm of inter-rows, tillage places, trodden and rutty places, roadsides, boundary stripes and drainage ditches. In the examined orchards the occurrence of 186 species belonging to 39 botanical families was noted. The most numerously represented were: Asteraceae (21%), Poaceae (15%), Brassicacea (8%) and Fabaceae (7%). In the examined orchards, 60% of the found species occurred occasionally or rarely. Those species which were found at the 15% level were: Equisetum arvense, Polygonum aviculare, Chenopodium album, Amaranthus retroflexus, Stellaria media, Capsella bursa-pastoris, Convolvulus arvensis, Viola arvensis, Epilobium adenocaulon, Conyza canadensis, Taraxacum officinale, Poa annua, and Echinochloa crus-galli. All of these species which occurred at the 15% level were most frequently noted in the herbicide fallow and were recognised as the most significant orchard weeds. The most numerous group in the examined orchards was made up of the therophytes (50%), which predominated over hemicryptophytes (31%) and geophytes (10%). Apophytes - native species (59%) predominated over archeophytes (33%) and kenophytes (8%). Within the vascular flora of the examined orchards, those which were predominant were the segetal species (26%), ruderal species (21%) and meadow species (19%).


Author(s):  
Н. Н. Лунева

Цель исследования – выявление различий в видовом составе сорных растений в посевах зерновых культур в географически отдаленных регионах (СЗР и ЦЧР). Произведен сравнительный анализ данных обследования 30 полей зерновых культур в ряде районов Ленинградской области в 2014-2016 гг. и 29 полей в районах Липецкой области в 2016-2018 гг., осуществленных по оригинальной методике автора. Использованы традиционные методы флористического анализа, а также распределение видов по классам постоянства встречаемости. Различия между сегетальными элементами флоры зерновых культур двух областей заключаются в более высоких показателях флористического богатства и таксономического разнообразия в Ленинградской области, а также различной очередностью семейств в первых двух «триадах» сравниваемых флористических спектров. Более глубокие отличия заключаются не только в наличии дифференциальных видов (63 вида в посевах зерновых культур только в Ленинградской области и 45 видов в посевах зерновых только в Липецкой области), но и в разных показателях встречаемости одинаковых видов, засоряющих посевы зерновых культур в обоих регионах. К более высоким классам постоянства встречаемости в Ленинградской области, чем в Липецкой, относятся виды: Chenopodium album L., Tripleurospermum inodorum (L.) Sch. Bip., Matricaria discoídea DC., Taraxacum officinale Wigg., Thlaspi arvense L., Stellaria media (L.) Vill., Elytrigia repens (L.) Nevski, Capsella bursa-pastoris (L.) Medik., Fumaria officinalis L. и Fallopia convolvulus (L.) A. Loeve, Achillea millefolium L., Artemisia vulgaris L., Sonchus arvensis L., Myosotis arvensis (L.) Hill., Silene vulgaris (Moench) Garcke, Plantago major L., Persicaria lapathifolia (L.) S.F. Gray, Polygonum aviculare L. На территории Липецкой области такими видами являются – Silene praténsis (Rafn) Godr,. Echinochloa crusgalli (L.) Beauv., Galeopsis tetrahit L., Galium aparine L., Convolvulus arvensis L. В засоренности посевов ячменя в разных областях также выявлены различия: зарегистрировано 42 вида сорных растений в посевах ячменя только Ленинградской области (среди которых доминирует Matricaria discoídea DC.) и 31 вид в посевах ячменя только в Липецкой области (среди которых доминируют Echinochloa crusgalli (L.) Beauv., и Amaranthus retroflexus L.). Из 29 одинаковых видов в посевах ячменя обеих областей, в Ленинградской области преобладают Chenopodium album L., Fumaria officinalis L., Tripleurospermum inodorum (L.) Sch. Bip., а в Липецкой Convolvulus arvensis L., Galeopsis tetrahit L., Raphanus raphanistrum L. Следовательно, фитосанитарный прогноз распространения видов сорных растений в посевах зерновых культур в целом, и в посевах ячменя, в частности, как и системы защиты от сорных растений будут отличаться в двух сравниваемых регионах.


2019 ◽  
Vol 16 (3) ◽  
pp. 595-609
Author(s):  
Mohamed O. Badry ◽  
Tarek A. A. Radwan ◽  
Fatma A. A. Ayed ◽  
Mohamed G. Sheded

The present study was undertaken to survey the floristic composition in the islands and shorelines in Aswan Reservoir, south of the River Nile at Aswan Governorate, Egypt. Four elements of vegetation were analyzed: floristic composition, lifespan, life form, and phytogeographical affinities. A total of 165 species were recorded belonging to 134 genera in 45 families of vascular plants, of which six species were new to the flora of Aswan and Nubia (Amaranthus spinosus, Doellia bovei, Eleocharis parvula, Haematoxylum campechianum, Polygonum aviculare, and Pithecellobium dulce). The most represented families are Leguminosae, Poaceae, and Compositae. Species richness is highest in low-lying areas (shorelines) liable to flooding, compared to those of the islands in the river. The recorded flora consists of 50.91% perennials and 49.09% annuals. Therophytes and phanerophytes were the predominant life forms. Phytogeographical analysis revealed the prevalence of the pantropical (28.48%), palaeotropical (17.57%), and cosmopolitan (16.36%) plant species. Monoregional chorotype was represented by 29 species (17.58%) of the recorded flora with the Sudano-Zambezian species (11.52%) being the highest chorotype, while pure Mediterranean species were very poorly represented (3.63%). Biregional chorotype was represented by 25 species (15.15%), while the pluriregional chorotype was accounted for 2.43% of recorded species.


2013 ◽  
Vol 53 (2) ◽  
Author(s):  
Janusz Lipecki ◽  
Anna Janisz

From 1993 to 1997 a study of spatial distribution of most important weeds in apple orchard herbicide strips was performed. This study was continued in 1998, once the trees were cut down. As the time progressed, <i>Epilobium adenocaulon</i> Hausskn., <i>Chenopodium album</i> L., <i>Polygonum aviculare</i> L. and <i>Atriplex patulum</i> L. showed an increase in their occurrence. An opposite tendency was found with <i>Erigeron canadensis</i> L., <i>Convolvulus arvensis</i> L. and Taraxacum fficinale Web. Some species grew in patches (Convolvulus arvensis L., Chenopodium album L., <i>Atriplex patulum</i> L.), while the others appeared sporadically throughout the orchard. In 1998, the decrease of occurrence of <i>Epilobium </i> Haussk. was observed. Simultaneously, this was coupled with an increase of occurrence of <i>Taraxacum officinale</i> Web., <i>Erigeron caanadensis</i> L. and <i>Chenopodium album</i> L. The predominating species in 1998 was <i>Cerastium vulgatum</i> L., followed by <i>Lolium perenne</i> L., <i>Poa annua</i> L. and <i>Bromus mollis</i> L.


1971 ◽  
Vol 8 (3) ◽  
pp. 340-347 ◽  
Author(s):  
George S. Day ◽  
Roger M. Heeler

When the selection of a sample of stores or cities requires a high degree of similarity among the test units in order to ensure a sensitive experiment, the sample may no longer represent the market. These conflicting requirements can be satisfied by choosing the sample from clusters displayed in a reduced space representation of the market.


2017 ◽  
Vol 22 (4) ◽  
pp. 467
Author(s):  
Mahran Zeity ◽  
Nagappa Srinivas ◽  
Chinnamade Channegowde Gowda

Study of morphological characters of Tetranychus macfarlanei Baker & Pritchard and Tetranychus malaysiensis Ehara revealed high similarity by comparing all the important characters in addition to the characters pointed out by Ehara to separate those two species. Molecular phylogeny of seven Indian populations of T. macfarlanei and one population of T. malaysiensis from Philippines along with few distantly related species of Tetranychus was attempted. High degree of similarity between these two species at mitochondrial COI gene (96%) as well as ITS2 (rDNA) (96–99%) region was evident. Based on both morphological features and molecular data, T. malaysiensis is proposed as a junior synonym of T. macfarlanei based on ICZN’s law of priority. Also more female characters are prompted in this study to distinctly discriminate T. macfarlanei from its most resembling species, Tetranychus ludeni Zacher. Tetranychus macfarlanei has emerged as a pest of several cultivated crop plants in India. 


1991 ◽  
Vol 71 (3) ◽  
pp. 831-839 ◽  
Author(s):  
A. G. Thomas

Annual surveys for weeds of fields seeded to spring wheat, barley, oats, flax, and canola in Manitoba were conducted during 1978, 1979, and 1981. Fields were surveyed during July and early August each year using a stratified random sampling procedure. Data for the crops and years were combined for analysis. The frequency, the area infested, and the density of the infestation were determined for each species. These three measures of the abundance of the weed were combined into a single synthetic value called relative abundance. Nine of the 152 species recorded by the surveyors accounted for 77% of the total relative abundance. Ranked in order by relative abundance, these species were green foxtail (Setaria viridis (L.) Beauv.), wild oats (Avena fatua L.), wild buckwheat (Polygonum convolvulus L.), annual smartweed (Polygonum spp.), Canada thistle (Cirsium arvense (L.) Scop.), lamb's-quarters (Chenopodium album L.), wild mustard (Sinapis arvensis L.), perennial sow-thistle (Sonchus arvensis L.), and redroot pigweed (Amaranthus retroflexus L.). Green foxtail was the predominant weed with an abundance value three times larger than wild oats or wild buckwheat. The pattern of dominance found in Manitoba fields was similar to results from comparable surveys in Saskatchewan and North Dakota. Key words: Relative abundance, weed survey, weed density, green foxtail, wild oats, wild buckwheat


1998 ◽  
Vol 5 (3) ◽  
pp. 311-334
Author(s):  
Gerhard Van Den Heever

AbstractIn a comparative study the issue is raised about the relationship between the construction of the saviour-image in Christianity, Buddhism, Zoroastrianism and Hinduism. The historical links between these traditions are highlighted and then the article proceeds to argue that when compared, the projections of the images of Jesus and Buddha, Jesus and Zoroaster and Jesus and Krishna exhibit a high degree of similarity. In the process questions are asked about the nature of religion and the value of comparative study.


PEDIATRICS ◽  
1996 ◽  
Vol 97 (2) ◽  
pp. 179-184
Author(s):  
Bahman Joorabchi ◽  
Jeffrey M. Devries

Objective. To evaluate a 3-year experience with the Objective Structured Clinical Examinations (OSCEs) and to compare faculty expectations with resident performance. Design. Descriptive analysis of measures of resident performance. Setting. Community-based pediatric residency program in Michigan. Participants. One hundred twenty-six pediatric residents at all levels of training. Methods. The three examinations consisted of 36 to 42 5-minute stations, testing skills in physical examination, history, counseling, telephone management, and test interpretation. A committee of faculty and chief residents predetermined minimum pass levels for each resident level. Results were compared with other indices of resident performance. Results. There was evidence for content, construct, and concurrent validity, as well as a high degree of reliability. However, 40% to 96% of residents scored below the minimum pass levels for their levels. In each examination, third-year residents had the highest failure rates, yet they scored well on the American Board of Pediatrics in-training examination and on their monthly clinical evaluations. Furthermore, for residents at all levels, the scores reflecting application of data were significantly lower than those assessing data gathering. Conclusions. The gaps between expectations and performance, and between data gathering and application, have important implications for institutional educational philosophy, suggesting a shift toward more clinically oriented and learner-directed strategies in the design of instructional and evaluation methods.


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