Journal articles on the topic 'Dicotyledonous flora'
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1
Wheeler, Elisabeth A., and Pieter Baas. "A Survey of the Fossil Record for Dicotiledonous Wood and its Significance for Evolutionary and Ecological Wood Anatomy." IAWA Journal 12, no. 3 (1991): 275–318. http://dx.doi.org/10.1163/22941932-90001256.
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Data on fossil dicotyledonous wood were assembled in order to 1) test the Baileyan model for trends of specialisation in dicotyledonous wood anatomy by addressing the question - were 'primitive' wood anatomieal features (as defined by the Baileyan model) more common in the geologie past than at present?, 2) infer, on a broad geographie scale, past climatie regimes, and long term climatic change, and 3) assess the extent of knowledge of fossil dicotyledonous woods. The resulting database has information on 91 anatomieal features for over 1200 fossil dicotyledonous woods. The incidence of selected anatomical features was plotted through time (by geologie epoch) for the world and for two regional groupings (roughly corresponding to the Laurasian and Gondwanan supercontinents). For comparison to the fossil wood record, the incidence of wood anatomie al features in the Recent flora was obtained from the 5260 record OPCN database for extant dicotyledonous woods.
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Sadyrova, G. A., T. A. Bazarbaeva, D. K. Bayzhigitov, and S. M. Jamilova. "Biodiversity of the meadow floristic complex of the ridge Ketpen-Temerlik." BULLETIN of the L.N. Gumilyov Eurasian National University. BIOSCIENCE Series 136, no. 3 (2021): 13–25. http://dx.doi.org/10.32523/2616-7034-2021-136-3-13-25.
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This article presents results of long-term studies of the meadow flora of the Ketpen-Temerlik ridge within Kazakhstan and China. The article presents an analysis of the meadow floristic complex of the Ketpen-Temerlik ridge. The taxonomic diversity of species composition of meadow floristic complex, biomorphological analysis of life forms of meadow species, and also the belonging of meadow species to different geographical types of areas. A detailed floristic analysis of meadow flora made it possible to identify 624 species of vascular plants belonging to 230 genera and 47 families. According to the main taxonomic groups of plants, the meadow flora is represented by the Magnoliophyta department, which accounts for 82.2% of the total species composition, and only an insignificant percentage is in the Liliopsida department, 17.1%. The ratio of monocotyledonous and dicotyledonous plants in meadow flora is 1: 4.8. The total number of monocotyledons covers 107 species or 17.1% of the total number of species, there are 517 species of dicotyledonous plants or 82.2%. Analysis of the largest families of meadow flora made it possible to identify 16 largest families by the largest number of species, which contain 504 species. Analysis of the species richness of the genera of flora are: Potentilla, Carex, Ranunculus, Taraxacum, Astragalus, Silene, Veronica. The leading genus of meadow flora accounts for 25.1%. The article considers a boreal nature of the meadow flora. The article reveals a large presence among the meadow flora of Ketpen-Temerlik of mountainous middle asian species with an area limited to the territories of Mountainous Middle Asia.
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Wheeler, Elisabeth A., and Pieter Baas. "The potentials and limitations of dicotyledonous wood anatomy for climatic reconstructions." Paleobiology 19, no. 4 (1993): 487–98. http://dx.doi.org/10.1017/s009483730001410x.
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The incidences of selected features of dicotyledonous wood that are believed to be of ecologic and/or phylogenetic significance (distinct growth rings, narrow and wide vessel diameter, high and low vessel frequencies, scalariform perforations, tangential vessel arrangement, ring porosity, and helical wall thickenings) were plotted through time (Cretaceous–Recent). There are marked differences between the Cretaceous and Tertiary in the frequency of all wood anatomical features. Incidences of features that are associated with markedly seasonal climates in extant floras do not approach modern levels until the Neogene. Correlations of wood anatomical features with ecology do not appear to have been constant through time, because in the Cretaceous different features provide conflicting information about the climate. Throughout the Tertiary the southern hemisphere/tropical and the northern hemisphere/temperate regions differed in the incidences of ecologically significant features and these differences are similar to those in the Recent flora. Possibilities for reliably using dicotyledonous wood for climatic reconstructions appear restricted to the Tertiary and Quaternary. However, at present the fossil wood record for most epochs and regions is too limited to permit detailed reconstructions of their past climate.
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Borkar, S. U., V. D. Nagrale, S. M. Meshram, A. N. Korpenwar, and D. D. Ramteke. "Taxonomical identification of a new petrified multiseeded capsular fruit from the Deccan Intertrappean beds of Bhutera, India." Journal of Palaeosciences 65, no. (1-2) (December 31, 2016): 271–76. http://dx.doi.org/10.54991/jop.2016.314.
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The fossil flora of the Deccan Intertrappean beds of central India provides a unique opportunity for detailed investigation, taxonomic affinities and biogeographic relationships of plants during the late Cretaceous–early Palaeogene Period. The fossils found in cherts were deposited during quiescent intervals of lava flows.
The present paper deals with a fossil fruit collected from the Deccan Intertrappean beds of Bhutera (lat. 22º06.58' N, long. 79º08.42' E) of Chhindwara District, Madhya Pradesh, India. The fruit was exposed in transverse oblique plane. The serial peel sections were taken for detailed study. The present fruit is small, dicotyledonous, obovate, unilocular, multiseeded, dehiscent capsular fruit. On comparison with modern dicotyledonous families, the fruit shows a close resemblance with Portulacaceae.
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Al-Eisawi, Dawud M. "Notes on the Flora of Jordan 13. New and Noteworthy Dicotyledonous Plants." Kew Bulletin 41, no. 4 (1986): 949. http://dx.doi.org/10.2307/4102991.
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Dillhoff, Richard M., Estella B. Leopold, and Steven R. Manchester. "The McAbee flora of British Columbia and its relation to the Early-Middle Eocene Okanagan Highlands flora of the Pacific Northwest." Canadian Journal of Earth Sciences 42, no. 2 (February 1, 2005): 151–66. http://dx.doi.org/10.1139/e04-084.
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Megafossils and pollen data are used to compare the flora found at the McAbee site, located near the town of Cache Creek, British Columbia, to six other well-collected Eocene lacustrine floras of Washington and western British Columbia. A diverse flora is found at McAbee consisting of at least 87 taxa. Gymnosperms are common, including sixteen separate species, 14 conifers and two ginkgos. A minimum of 67 angiosperm genera are represented in the flora, many yet to be described. The dominant dicotyledonous elements of the leaf assemblage at McAbee include Fagus (also represented by nuts and cupules) with Ulmus and representatives of the Betulaceae, especially Betula and Alnus. The confirmation of Fagus, also rarely found from sites at Princeton, British Columbia, and Republic, Washington, provides the oldest well-documented occurrence of the genus, predating the Early Oligocene records of Fagus previously reported for North America, Asia, and Europe. Data provided by pollen analysis broadens our knowledge of the McAbee flora. Angiosperm pollen typically predominates over gymnosperms with the Ulmoideae and Betulaceae being the most common angiosperm pollen types. Members of the Pinaceae dominate the gymnosperm pollen record. Paleoclimatic estimates for McAbee are slightly cooler than for the Republic and Princeton localities and thermophilic elements, such as Sabal found at Princeton or Ensete and Zamiaceae found at Republic are not known from McAbee.
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Panfilov, A. E., N. I. Kazakova, N. N. Zezin, E. L. Tikhanskaya, and P. Yu Ovchinnikov. "Taxonomic composition of weed vegetation in the southern and middle Urals and zonal features of its control in maize crops." E3S Web of Conferences 222 (2020): 03024. http://dx.doi.org/10.1051/e3sconf/202022203024.
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As a result of expeditionary-route studies, the impoverishment of the composition of the segetal flora in maize crops was established when moving from the North-West to the South-East of the Ural region: from 37 species in the forest-meadow and mountain-forest zones to 10 in the steppe zone. Zonal features of the composition of weed communities associated with the hydrothermal gradient consist in the mutual substitution of annual monocotyledonous and dicotyledonous species with a stable contribution of perennial dicotyledons, as well as the replacement of mesophytic weeds with xerophytic species of the same families. A comparison of cross-spectrum herbicides effectiveness in the forest-steppe and forest-meadow zones showed the advantages of a post-emergent preparation with soil effect of Meister Power. In temperate soil fertility in the Southern area of the region, it is economically feasible to use post-emergent herbicides without soil effect, in Northern areas with stable moisture – soil ones.
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Balan, Anoop P., and S. Harikrishnan. "Floristic diversity of the Indian Cardamom Research Institute campus, Myladumpara, Western Ghats, India." Journal of Threatened Taxa 9, no. 10 (October 26, 2017): 10804. http://dx.doi.org/10.11609/jott.2611.9.10.10804-10822.
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A study on the flora of Indian Cardamom Research Institute campus, Myladumpara was carried out during 2012–2015 and a total of 515 taxa were collected during this study. The indigenous or naturalized flora is represented by 392 taxa in 303 genera under 94 families. Dicotyledonous plants dominate with 335 species in 251 genera under 80 families. Monocotyledons are represented by 57 species in 52 genera under 14 families. Among the families, Fabaceae dominates with 29 species followed by Asteraceae (27 spp.) and Euphorbiaceae (22 spp.) and 40 families are represented by single species each. During the study 68 species that are considered as endemic to the Western Ghats could be collected.
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Takahashi, Ken'ichi, and Mitsuo Suzuki. "Dicotyledonous Fossil Wood Flora and Early Evolution of Wood Characters in the Cretaceous of Hokkaido, Japan." IAWA Journal 24, no. 3 (2003): 269–309. http://dx.doi.org/10.1163/22941932-90001597.
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Fossil woods are abundant in the Cretaceous Yezo Group in Hokkaido, Japan, in strata of Albian to Santonian ages. From 144 dicotyledonous samples, fourteen species representing 10 genera were identified: Castanoradix cretacea gen. et sp. nov., C. biseriata gen. et sp. nov., Frutecoxylon yubariense gen. et sp. nov., Hamamelidoxylon obiraense sp. nov., Icacinoxylon kokubunii sp. nov., I. nishidae sp. nov., Magnoliaceoxylon hokkaidoense sp. nov., Nishidaxylon jezoense gen. et sp. nov., Paraphyllanthoxylon cenomaniana sp. nov., P. obiraense sp. nov., Plataninium jezoensis sp. nov., P. ogasawarae sp. nov., Sabiaceoxylon jezoense gen. et sp. nov. and Ulminium kokubunii sp. nov. All 14 species are new and four of the 10 genera are new. Five genera (lcacinoxylon, Magnoliaceoxylon, Paraphyllanthoxylon, Plataninium and Ulminium) already are known from the Cretaceous and Tertiary, one (Hamamelidoxylon) previously is known only from the Tertiary. The species distribution by age is: Albian: one species; Cenomanian: four species in four genera; Turonian: ten species in eight genera; Coniacian: six species in five genera; Santonian: eight species in seven genera. The two specimens of Icacin oxylon kokubunii from the Albian are the oldest records of dicotyledonous woods in Japan.
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Prasad, M., J. S. Antal, and V. D. Tiwari. "Investigation on plant fossils from Seria Naka in the Himalayan foot-hills of Uttar Pradesh, India." Journal of Palaeosciences 46, no. 3 (December 31, 1997): 13–30. http://dx.doi.org/10.54991/jop.1997.1344.
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A floral assemblage consisting of leaf-impressions recovered from the Lower Siwalik sediments of Seria Naka, about 30 km north-west of Tulsipur town in Gonda District of Uttar Pradesh, India has been described and discussed in the present paper. The assemblage comprises 10 taxa belonging to seven dicotyledonous families - Anonaceae, Flacourtiaceae, Polygalaceae, Sapindaceae, Anacardiaceae, Fabaceae and Ebenaceae. An analysis of the floral assemblage with respect to the distribution pattern of modem equivalent taxa reveals the prevalence of warm and humid climates in the region during the deposition of these sediments. The fossil flora also indicates that tropical evergreen forests with few moist deciduous plants were flourishing around Seria Naka in the Himalayan foot-hills during Middle Miocene in contrast to the mixed deciduous type of present-day forests. Further, the presence of some Malayan elements like Goniothalamus meboldii, Mitrephora macrophylla and Nephelium glabrum is phytogeographically important supporting the view of the migration of some taxa from Southeast Asia to the Indian subcontinent during the Neogene.
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Clarkson, JR, and HT Clifford. "Germination of Jedda multicaulis Clarkson,J.r. (Thymelaeaceae). An Example of Cryptogeal Germination in the Australian Flora." Australian Journal of Botany 35, no. 6 (1987): 715. http://dx.doi.org/10.1071/bt9870715.
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The germination of Jedda multicaulis is figured and described. It provides the first record of cryptogeal germination for a member of the family Thymelaeaceae and demonstrates the habit for the first time in a woody dicotyledonous member of the Australian flora. Anatomical studies show the burying of the plumule is the result of a modification of the cotyledonary petioles. The germination pattern is considered to be primarily an adaptation to fire. It also provides a mode of recovery following grazing or trampling.
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Awasthi, N., and R. C. Mehrotra. "Oligocene flora from Makum Coalfield, Assam, India." Journal of Palaeosciences 44 (December 31, 1995): 157–88. http://dx.doi.org/10.54991/jop.1995.1207.
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The coal bearing Oligocene sediments exposed in the Makum Coalfield, Assam contain rich assemblage of mega-plant remains. Out of a large number of leaves and fruits collected from the associated sediments at Baragolai. Ledo-Tirap and Tipongpani collieries of the Makum Coalfield, 24 species of dicotyledonous taxa have been identified. Of these, 22 are represented by leaves belonging to the genera Saccopetalum (Anonaceae); Calophyllum, Garcinia, Kayea (Clusiaceae); Pterygota (Sterculiaceae); Santiria (Burseraceae); Heynea (Meliaceae); Nephelium (Sapindaceae); Lannea, Mangifera, Parishia (Anacardiaceae); Rhizophora (Rhizophoraceae); Terminalia (Combretaceae); Memecylon (Memecylaceae); Avicennia (Avicenniaceae); Alstonia (Apocynaceae); Myristica (Myristicaceae), Apollonias (Lauraceae) and Bridelia (Euphorbiaceae). The remaining two taxa are based on fruit/seed comparable to those of Dalbergia and Entadu of Fabaceae.
The distribution pattern of comparable modern taxa of fossils and keeping in view the great amount and variety of plants preserved in the sediments, it is inferred that thick tropical evergreen to moist deciduous forest existed in this part of northeast India during Oligocene. Occurrence of Avicennia, Rhizophora and Terminalia catappa suggests deltaic, mangrove or agoonal deposition of coalseams and associated sediments in the Makum Coalfield.
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Knyazev, Mikhail, Elena Podgaevskaya, Natalia Zolotareva, Alyona Tretyakova, and Pavel Kulikov. "Annotated checklist of the flora of Sverdlovsk Region. Part VII: Dicotyledonous plants (Asteraceae, Cichorioideae)." Diversity of plant world 4 (11) (December 24, 2021): 5–33. http://dx.doi.org/10.22281/2686-9713-2021-4-5-33.
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This article for the first time presents a detailed checklist of the flora of dicotyledonous plants (Asteraceae, Cichorioideae) of Sverdlovsk Region, based on the long-term filed research, a critical study of herbarium materials and literature sources. Part VII of the checklist includes 91 species and 6 interspecific hybrids of wild plants. The information on all the species is given on the occurrence in botanical-geographical districts and administrative districts of the region. In the checklist for species bioecological features are indicated (life form according to K. Raunkiaer and I. G. Serebryakov, coenotic groups and ecological groups in relation to moistning), zonal and longitudinal arealogic group, economic significance. As for the alien species, origin, migration thecnique, and level of naturalization achieved in the region are additionally indicated. Species that need protection in the region are noted.
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Prasad, Mahesh, J. S. Antal, P. P. Tripathi, and V. K. Pandey. "Further contribution to the Siwalik flora from the Koilabas area, western Nepal." Journal of Palaeosciences 48, no. (1-3) (December 31, 1999): 49–95. http://dx.doi.org/10.54991/jop.1999.1291.
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The present study on fossil plants comprising well-preserved leaf and fruit impressions from the Siwalik sediments exposed near Koilabas in western Nepal is the first detailed and systematic work. The floral assemblage recovered from these sediments is impoverished both in quality and quantity as constituted by 25 species belonging to 22 genera and 15 dicotyledonous families of angiosperms. This assemblage adds significant data to the Siwalik Palaeobotany. On the basis of present assemblage as well as already known data from the area, the palaeoclimate, palaeoecology, and phytogeography of the area during the Mio-Pliocene in the Himalayan foothills have been deduced. The significance of the physiognomic characters of the fossil leaves in relation to climate has also been discussed.
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Galaktionova, E. V., and E. V. Rachkauskene. "SYSTEMATIC ANALYSIS OF REPRESENTATIVES OF THE LEGUME FAMILY (FABACEAE) IN THE FLORA OF THE SURROUNDINGS OF YASNOVSKY RURAL DISTRICT, YESILSKY DISTRICT, NORTH KAZAKHSTAN REGION." Vestnik of M. Kozybayev North Kazakhstan University, no. 4 (52.1) (June 13, 2023): 7–13. http://dx.doi.org/10.54596/2309-6977-2021-4-7-13.
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Representatives of the Legume family (Fabaceae) play an important role in the formation of biocenoses and create accessory conditions for the regulation of processes that occur in natural communities. Legumes are one of the largest families of dicotyledonous plants of the order Leguminous, which has been poorly studied in the territory of the North Kazakhstan region. As a result of the study, an analysis of the flora in the vicinity of the Yasnovsky rural district, the Yesilsky district of the North Kazakhstan region was carried out, which made it possible to study the quantitative and qualitative composition of representatives, to determine the status of occurrence.
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Stockey, Ruth A., Georgia L. Hoffman, and Gar W. Rothwell. "Paleobotany and paleoecology of Gao Mine, a late Paleocene fossil locality near Red Deer, Alberta, Canada." Canadian Journal of Earth Sciences 50, no. 3 (March 2013): 235–48. http://dx.doi.org/10.1139/cjes-2012-0073.
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In addition to having a rich assemblage of mammalian fossils, the Gao Mine locality in the Paskapoo Formation of south-central Alberta has yielded numerous plant specimens of late Paleocene (late Tiffanian or Ti5) age. The plant fossils are preserved in siltstones and fine-grained sandstones interpreted as overbank sediments that were deposited on an aggrading floodplain. The assemblage is dominated by the cupressaceous conifer Metasequoia foxii and the cercidiphyllaceous dicot Joffrea speirsiae, including their well-preserved seedlings. The flora also contains foliage of the ferns Onoclea and Speirseopteris and the woody dicots Palaeocarpinus, Aphananthe/Celtis, Aesculus, Beringiaphyllum, ?Trochodendron, and Wardiaphyllum, as well as seedlings of unknown dicotyledonous angiosperms. Metasequoia foxii and Speirseopteris are unique to the floras of Gao Mine and the nearby Munce’s Hill site (Tiffanian Ti4). The remainder of the taxa are common in late Paleocene floras of North Dakota, Montana, and Wyoming, all USA. The floras of the nearby Joffre Bridge Roadcut and Blindman River sites (both Tiffanian Ti3) are more diverse, but both of those sites encompass a wider range of depositional environments and may include higher percentages of allochthonous material. Most of the Gao Mine material is autochthonous. The seedlings were buried in place, along with the surrounding leaf litter, preserving a record of the local plant community.
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Srivastava, Rashmi, D. K. Kapgate, and Shantanu Chatterjee. "Permineralized fungal remains in the fossil wood of Barringtonia from the Deccan Intertrappean sediments of Yavatmal District, Maharashtra, India." Journal of Palaeosciences 58, no. (1-3) (December 31, 2009): 11–19. http://dx.doi.org/10.54991/jop.2009.77.
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Fungal infection (parasitism and saprophytism) in the fossil flora of Deccan Intertrappean sediments is well documented from Chhindwara, Dindori, Mandla, Nagpur and Seoni areas of central India. In the present communication, a well preserved dicotyledonous fossil wood showing resemblance with the extant genus Barringtonia Forster & G. Forster of the family Lecythidaceae is recorded for the first time from the Yavatmal District, Maharashtra. The anatomical study of wood reveals that it is endogenously infected with saprophytic fungus Epicoccum Link. ex Schlecht and fungal conidia are profusely distributed in the vessels of the fossil wood. Very fine, ill preserved mycelium is also seen at places. Presence of the genus Barringtonia, as well as fungus Epicoccum is indicative of warm and humid conditions in the area during the time of deposition of intertrappean sediments.
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Prasad, M., and N. Awasthi. "Contribution to the siwalik flora from Surai Khola sequence, western Nepal and its palaeoecological and phytogeographical implications." Journal of Palaeosciences 43, no. 1-3 (December 31, 1994): 1–42. http://dx.doi.org/10.54991/jop.1994.1184.
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A systematic study of plant megafossils comprising mostly leaf-impressions and few fruits from a sequence of the Siwalik sediments of Surai Khola area, Rapti Anchal, western Nepal has revealed 33 taxa belonging to 15 dicotyledonous families, viz., Anonaceae, Flacourtiaceae, Clusiaceae, Rutaceae, Meliaceae, Sapindaceae, Anacardiaceae, Fabaceae, Anisophylleaceae, Myrtaceae, Rubiaceae, Apocynaceae, Ebenaceae, Euphorbiaceae and Moraceae. Amongst them, Goniothalamus, Harpullia, Anisophyllea, Anthocephalus, Diplospora, Chonemorpha and Cleistanthus are new genera to the Indian Tertiary flora. The megafloral assemblage of the Surai Khola sequence, including 21 taxa reported earlier, now comprises 53 taxa of angiosperms. Most of the extant species resembling the fossil taxa are distributed in tropical evergreen to semi-evergreen forests of Western Ghats, northern India, Andaman Islands, Bangladesh, Myanmar and in Southeast Asia which suggest that warm humid climate with higher precipitation prevailed in the area during Middle Miocene-Pliocene. Looking at the floral assemblages of different formations of the Surai Khola sequence, from base to the top sediments belonging to the Lower, Middle and Upper Siwaliks, one may find a gradual shift in the vegetation pattern. The basal sediments of Bankas and Chor Khola formations have preponderance of a lowland mixed mesophytic broad leaved evergreen to semi-evergreen elements. An increase in deciduous elements in the floral composition consequent to the disappearance of dipterocarpus and other significant evergreen taxa is noticed towards the close of Middle Siwalik and the beginning of Upper Siwalik. This change in the vegetation pattern reflects the changes in climatic conditions which are mainly due to northward movement of the Indian Plate and further uplift of Himalaya.
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LOCATELLI, EMMA R., DEREK E. G. BRIGGS, ANDREW LESLIE, JÉRÔME MUNZINGER, PHILIPPE GRANDCOLAS, PORTER P. LOWRY, DAVID J. CANTRILL, et al. "LEAVES IN IRON OXIDE: REMARKABLE PRESERVATION OF A NEOGENE FLORA FROM NEW CALEDONIA." PALAIOS 37, no. 10 (October 20, 2022): 622–32. http://dx.doi.org/10.2110/palo.2022.019.
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Abstract A Neogene hematite-goethite concretionary ‘ironstone' horizon in laterized fluvial sediments in the Massif du Sud of New Caledonia yields abundant fossil dicotyledonous angiosperm leaves. The leaves are preserved in iron oxide, mainly goethite, which replicates the morphology and anatomy of the leaf tissues and comprises 73% of the matrix. Organic remains are minimal and associated with aluminosilicate clay. Leaf tissues are preserved three-dimensionally in multiple ways including casts/molds, permineralization/petrifaction, and replacement. Although the mesophyll is less well preserved, reflecting its greater susceptibility to decay, cellular details of vascular and epidermal tissues are commonly evident. Analyses of leaves from an analogous modern setting reveal the early encrustation and impregnation of tissues by amorphous iron-oxides and clays in association with a microbial biofilm. We propose a taphonomic model in which the fossil leaves, like their modern counterparts, were permeated by iron oxides due to the high availability of iron derived from weathering of ultramafic basement. In contrast to the iron-rich aluminosilicate coatings that form in relatively iron-poor settings, the unusually high concentration of dissolved iron oxides permitted rapid anatomical preservation.
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Yankova, Elina, Petka Grancharova, and Rozalia Nikolova. "On the Reproductive Biology of Alkanna tinctoria (Boraginaceae)." Proceedings of the Bulgarian Academy of Sciences 75, no. 7 (July 29, 2022): 1000–1008. http://dx.doi.org/10.7546/crabs.2022.07.08.
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In the present study main parameters of reproductive biology as features of embryological structures and processes as well as the pollen and seed viability of Alkanna tinctoria, an endangered useful species of Bulgarian flora were established. In its studied Bulgarian populations pollen viability above 90% and seed viability – between 32% and 64% were determined. The anthers are tetrasporangiate and their wall develops according to Dicotyledonous-type, consisting of an epidermis, fibrous endothecium, an ephemeral middle layer and secretory tapetum. The microsporogenesis is simultaneous and in the anthers tetrahedral and isobilateral microspore tetrads are formed. The mature pollen is threecelled at shedding stage. The ovule is anatropous, teniunucellate, unitegmic. Embryo sac (ES) develops according to the Polygonum (monosporic)-type. The embryo development follows the Asterad-type. The endosperm in the mature seeds has been completely consumed. As a result of the present study A. tinctoria is characterized as a sexually reproducing species.
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Grădilă, Marga, Daniel Jalobă, Valentin Marius Ciontu, and Raluca Monica Cristea. "RESEARCH CONCERNING FLORISTIC COMPOSITION AND DEGREEE OF WEED INFESTATION OF CEREAL CROPS IN CONSTANTA COUNTY." Romanian Journal for Plant Protection 14 (2021): 106–13. http://dx.doi.org/10.54574/rjpp.14.14.
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"Weeds mapping aims to know the segetal floristic spectrum from the point of view of the degree of weed infestation and the frequency of weeds in each crop. Cereals crops are yearly infested by dicotyledonous and monocotyledonous weeds species, annual and perennial, some of them being very harmful, difficult to control and known as dominant weeds or problem weeds. Research carried out in Constanța county, Agigea and Runcu villages, during 2020-2021 years, was concerned with segetal flora assessment. The main purposes considered were: the study of the issues related to the floristic composition, the dynamics of the degree of weed infestation, the identification of the dominant species, the establishment of the most effective herbicide treatments and of the optimal times of application. The analysis of the obtained data reveals that the problem weeds with a density >10 plants/m2 identified in the wheat and barley crops in Agigea were: Veronica species, Papaver rhoeas, Chenopodium album, Polygonum convolvulus and Fumaria officinalis. The dominant weed species in wheat and barley crops of Runcu were: C. album, Convolvulus arvensis, Stellaria media, Equisetum arvense and Cannabis ruderalis. Although the dicotyledonous species prevail in both studied places, the weed control strategy is different because the target species against which control measures must be applied are different and consequently the range of herbicides will also be different. The results obtained fully justify the weed mapping action because it is a tool that offers the farmer the exact perception regarding the degree of weed infestation in the studied areas. Mapping thus becomes a very useful work for weed control practice."
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Friis, Else Marie, Peter R. Crane, and Kaj Raunsgaard Pedersen. "Extinct Taxa of Exotestal Seeds Close to Austrobaileyales and Nymphaeales From the Early Cretaceous of Portugal." Fossil Imprint 74, no. 1-2 (August 31, 2018): 135–58. http://dx.doi.org/10.2478/if-2018-0010.
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Early Cretaceous mesofossil floras from Portugal and North America include a surprising diversity of small, bitegmic angiosperm seeds with a hard exotestal seed coat. This study describes six different kinds of these seeds from three Portuguese mesofossil localities; Vale de Agua, Torres Vedras, and especially from Famalicão, which has yielded a flora exceptionally rich in exotestal seeds. All the seeds are almost smooth with a characteristic jigsaw puzzle-shaped surface pattern that is formed from the strongly undulate anticlinal walls of the sclerenchyma cells that comprise the exotesta. Several specimens have internal details preserved, including remains of a cellular nutritive tissue interpreted as endosperm, and a tiny embryo with two rudimentary cotyledons. Based on differences in details of the seed coat, and configuration of hilum and micropyle, the fossil seeds are assigned to six new genera, as six new species: Gastonispermum portugallicum gen. et sp. nov., Pazlia hilaris gen. et sp. nov., Pazliopsis reyi gen. et sp. nov., Reyispermum parvum gen. et sp. nov., Lusitanispermum choffatii gen. et sp. nov. and Silutanispermum kvacekiorum gen. et sp. nov. The characteristic exotestal cells with undulate anticlinal walls, details of the hilar and micropylar region, together with the tiny dicotyledonous embryos with rudimentary cotyledons, suggest close relationships to seeds of Nitaspermum and Tanispermum described previously from Early Cretaceous mesofossil floras from eastern North America. These exotestal seeds from Portugal and North America indicate the presence of diverse extinct early angiosperms close to the lineages that today include extant Austrobaileyales and Nymphaeales.
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Singh, Sanjai Kumar, and Mahesh Prasad. "Fossil leaf-impressions from the Late Tertiary sediments of Mahuadanr Valley, Latehar District, Jharkhand, India." Journal of Palaeosciences 57, no. (1-3) (December 31, 2008): 479–95. http://dx.doi.org/10.54991/jop.2008.266.
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Morphotaxonomical study of the leaf impressions collected from the Late Tertiary sediments of Mahuadanr Valley, Jharkhand, India has been done. The comparison of morphological features between the fossils and extant taxa revealed the occurrence of 13 species of 5 dicotyledonous families. On the basis of present assemblage, the palaeoclimate and phytogeography of Mahuadanr area during the Late Tertiary have been deduced. Present distribution of all the modern comparable species of the fossils indicates that these are presently found to grow in the tropical forests of the Himalayan foot hills, central India, south India and adjoining area of the Mahuadanr Valley, suggesting a mixed, mesophytic type of forest was flourishing in and around the fossil locality during the sedimentation. As most of the comparable species are found now-a-days in the vicinity of fossil locality of Mahuadanr it indicates that same flora has continued till now which suggests that there has been no marked climatic change in the area since the Late Tertiary time.
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Nerlekar, Ashish N., Sairandhri A. Lapalikar, Akshay A. Onkar, S. L. Laware, and M. C. Mahajan. "Flora of Fergusson College campus, Pune, India: monitoring changes over half a century." Journal of Threatened Taxa 8, no. 2 (February 26, 2016): 8452. http://dx.doi.org/10.11609/jott.1950.8.2.8452-8487.
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<p>The present study was aimed at determining the vascular plant species richness of an urban green-space- the Fergusson College campus, Pune and comparing it with the results of the past flora which was documented in 1958 by Dr. V.D. Vartak. For this, the species richness data was obtained by both secondary sources and intensive surveys from 2009–2014. The data from the primary and secondary sources resulted in the documentation of 812 species belonging to 542 genera under 124 families, of which 534 species (65.8%) exists today as compared to 654 in 1958 (net loss of 120 species). Of the 812 species listed, 278 species were observed only during the past, 210 species were exclusively recorded in the current survey and 324 species were observed both, in the past as well as current survey. Arboreal species richness recorded till date (196) in the campus accounts for 40.7% of that of the entire Pune City. Leguminosae and Poaceae were the dominant dicotyledonous and monocotyledonous families respectively and an inventory of all the species recorded is provided. Although the botanical garden over the past years has lost 187 species, it still houses rare species such as <em>Acacia greggii,</em> which has been reported from Maharashtra for the first time. Considering the rapidly changing urban land use in the city, much attention should be paid towards the conservation of these green spaces, for which such studies provide baseline data.</p><div> </div>
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Harris, Elisha B., and Nan Crystal Arens. "A mid-Cretaceous angiosperm-dominated macroflora from the Cedar Mountain Formation of Utah, USA." Journal of Paleontology 90, no. 4 (July 2016): 640–62. http://dx.doi.org/10.1017/jpa.2016.44.
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AbstractAngiosperms first appeared in the fossil record as pollen during the Valanginian–Hauterivian; they spread out of the tropics in the Aptian and Albian, and radiated in the Late Cretaceous. Despite these general patterns, details of the taxonomic, geographic, and ecological evolution of Cretaceous angiosperms are relatively poorly known because only a handful of Early and mid-Cretaceous macrofloras have been reported. This is the first detailed report of a fossil leaf flora from the Cedar Mountain Formation from the mid-Cretaceous of the Western Interior. We describe a flora that is overwhelmingly dominated by angiosperms (152 of 153 identified specimens are angiosperms) from the Albian–Cenomanian transition that is preserved in a clay- and carbonate-rich, lacustrine mudstone from the uppermost Cedar Mountain Formation of Emery County, Utah. We recognize 18 leaf morphotypes, all of which are dicotyledonous angiosperms. The majority of the Cedar Mountain morphotypes have taxonomic affinities with forms of similar age described from the Atlantic and Gulf coastal plains and other localities from the Western Interior. From this, we infer that a relatively diverse angiosperm flora grew along the margins of a small pond on the coastal plain. Palynological preparations of the fossil matrix were barren; however, previous studies of other facies within the formation showed that both conifers and ferns were important components of the regional vegetation during Cedar Mountain time. The effective absence of conifers and ferns in this macroflora and low leaf mass per area values among the angiosperms measured suggests that even at the Early–Late Cretaceous transition, angiosperms had come to dominate some sites, particularly those that were disturbed or seasonally ephemeral, where fast-growth or seasonal deciduousness would have been favored.
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HODGSON, J. G., and J. M. L. MACKEY. "THE ECOLOGICAL SPECIALIZATION OF DICOTYLEDONOUS FAMILIES WITHIN A LOCAL FLORA: SOME FACTORS CONSTRAINING OPTIMIZATION OF SEED SIZE AND THEIR POSSIBLE EVOLUTIONARY SIGNIFICANCE." New Phytologist 104, no. 3 (November 1986): 497–515. http://dx.doi.org/10.1111/j.1469-8137.1986.tb02916.x.
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Suzuki, Mitsuo, and Kazuo Terada. "Fossil Wood Flora from the Lower Miocene Yanagida Formation, Noto Peninsula, Central Japan." IAWA Journal 17, no. 4 (1996): 365–92. http://dx.doi.org/10.1163/22941932-90000634.
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Silicified woods from the lower Miocene Yanagida Formation were collected from two sites, Mawaki and Uchiura, in the northeastern Noto Peninsula, central Japan. Among 80 specimens, 15 species representing 13 families were identified, including six new species: Torreya mioxyla (Taxaceae), Castanopsis uchiuraensis (Fagaceae), Camellia japonoxyla (Theaceae), Stewartia notoensis (Theaceae), Distylium chiharu-hirayae (Hamamelidaceae) and Aesculus mioxyla (Hippocastanaceae). The fossil wood floras from these two sites contain evergreen and deciduous dicotyledons and have a similar composition. These floras are compared to the fossil wood flora from Monzen and to the Daijima-type compression fossil flora. The composition of the fossil wood floras of Mawaki and Uchiura suggests they represent a mixed mesic forest of conifers, deciduous dicotyledons and evergreen dicotyledons.
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TATOJ, Agnieszka, Katarzyna MOŻDŻEŃ, Beata BARABASZ-KRASNY, Anna SOŁTYS-LELEK, Wojciech GRUSZKA, and Peiman ZANDI. "Effect of Rosa gorenkensis Besser aqueous extracts on germination and early growth of native plant species." Notulae Botanicae Horti Agrobotanici Cluj-Napoca 50, no. 1 (March 24, 2022): 12668. http://dx.doi.org/10.15835/nbha50112668.
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In Europe, Rosa gorenkensis Besser is considered an invasive species. However, its negative impact on native flora components or other habitat components has not been described so far. In the experiment, the germination reactions of mono- and dicotyledonous plant seeds to the aqueous extracts of R. gorenkensis were investigated to determine the allelopathic potential of this plant. Seeds of common plants – wild-growing Festuca rubra L. and cultivated Raphanus sativus L. var. radicula Pers. cv. ‘Rowa’ were treated with aqueous extracts from the roots, stalks, leaves, and flowers of rosa at concentrations of 1%, 2.5%, and 5%. Along with the increase in the concentration of allelochemical compounds in the extracts, the negative influence of the extracts on the germination capacity of the tested seeds species was found. Regardless of the type of extract, inhibition of the growth of the underground and aboveground parts of seedlings was also observed. Changes in biomass and water content, depending on the concentration and type of the extract, were found. The greatest differences in the electrolytes leakage in seedlings watered with 5% extracts were revealed. The study showed that the aqueous extracts of leaves and flowers of this species had the greatest allelopathic potential.
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ŞIMON, Alina, Felicia CHEŢAN, Cornel CHEŢAN, and Marius BĂRDAŞ. "Influence of Tillage Systems on the Degree of Weeding on Agricultural Crops at ARDS Turda." Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca. Agriculture 76, no. 2 (November 18, 2019): 99. http://dx.doi.org/10.15835/buasvmcn-agr:2018.0029.
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Plants of spontaneous flora are in constant competition with culture plants for water, nutrients and other vegetation factors. The degree of weeding was determined in 2014-2016, at four crops - winter wheat, maize, soybeans and peas, cultivated in conventional tillage system and conservation tillage. Temperatures and precipitations registered on the vegetation period in three year had a high influence on the number of weeds found in agricultural crops, so in 2015 there was a smaller number of weeds than in 2014 respectively 2016. Of the species determined in this period is noted for annual dicotyledonous (most of them Chenopodium sp., Veronica sp. and Xanthium strumarium), and among the species of monocotyledonous species Echinochloa sp. and Setaria sp. which are found in all four cultures. In the case of the application of conservative tillage systems there is an increase in the number of weeds compared to the conventional tillage system. The average yields obtained by maize, soybean and peas at application of conservative tillage systems are close to the classical tillage system, the winter wheat yield was higher in the no tillage system than in the classical tillage system.
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Ullah, Shakir, Lubna Shakir, Ghani Subhan, Mohammad Sohail, Rizwana Bilqees, Yaseen Khan, Uroosa Gulzar, Sajid Ali, Zakir Ullah, and Shahab Ali. "Phytodiversity and Conservation Assessment of Ethnobotanically Significant Flora in Khall Hagram Dara, Lower Dir, Khyber Pakhtunkhwa, Pakistan." Plant Protection 8, no. 1 (March 27, 2024): 143–62. http://dx.doi.org/10.33804/pp.008.01.5084.
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The current research provides first-hand information about the flora and vegetation of Siyar Dara, consisting of 332 species and 97 families. Among these, 6 species are gymnosperms, while the remaining 326 species belong to 249 genera of angiosperms. Out of these 326 species, 47 species belong to 42 genera of monocotyledonous plants, and the remaining 279 species belong to 207 genera of dicotyledonous plants. Among all 97 families, Asteraceae was the largest family, with 23 genera (9.05%) and 30 species (9.03%). Following Asteraceae, Poaceae and Lamiaceae had 24 genera (9.44%) and 16 genera (6.29%) respectively, with 25 species (7.53%) and 22 species (6.62%) respectively. Rosaceae had 10 genera (3.93%) and 14 species (4.21%), Solanaceae had 7 genera (2.75%) and 10 species (3.01%), Scrophulariaceae had 6 genera (2.36%), Ranunculaceae had 5 genera (1.96%), and Polygonaceae had 5 genera (1.96%), each with 9 species (2.71%). Boraginaceae had 7 genera, Cucurbitaceae had 5 genera, and Euphorbiaceae had 4 genera (1.57%), each with 8 species (2.409%). Brassicaceae had 6 genera (2.36%), while Amaranthaceae and Apiaceae each had 5 genera (1.96%), and Moraceae had 2 genera (0.78%), all with 6 species (1.80%). Convolvulaceae, Salicaceae, and Valerianaceae each had 2 genera (0.78%) and 3 species (0.90%). Rubiaceae had 3 genera and 3 species. Acanthaceae, Alismataceae, Crassulaceae, Nytiginaceae, Primulaceae, Urticaceae, and Verbenaceae were represented by single genera and species. A total of 90 plants were found to be used for various purposes locally, including medicinal (27.7%), fodder (25.5%), miscellaneous (16.6%), fuelwood (11.1%), timber (8.8%), vegetables (8.8%), and ornamental (1%).
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Konomatsu, M., and N. Awasthi. "Plant fossils from Arung Khola and Binai Khola formations of Churia Group (Siwalik), west central Nepal and their palaeoecological and phytogeographical significance." Journal of Palaeosciences 48, no. (1-3) (December 31, 1999): 163–81. http://dx.doi.org/10.54991/jop.1999.1302.
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Systematic study of plant megafossils comprising dicotyledonous leaves and seeds collected from the Arung Khola and Binai Khola formations of the Churia Group, exposed in Tinau Khola and Mahendra Highway between Barghat and Dumkibas, Nepal, has revealed 15 taxa out of which 14 are new belonging to 14 genera of 12 families. They are named as Orophea siwalika sp. nov., Miliusa brochidodroma sp. nov. (Annonaceae); Gynocardia butwalensis sp. nov. (Flacourtiaceae); Shorea miocenica sp. nov., S. nepalensis sp. nov., Hopea siwalika Antal & Awasthi (Dipterocarpaceae); Grewia mallotophylla sp. nov. (Tiliaceae); Chisocheton ellipticus sp. nov., Ventilago ovatus sp. nov. (Rubiaceae), Swintonia butwalensis sp. nov. (Anacardiaceae); Mitragyna tertiara sp. nov., Mussaendopsis suborbiculatus sp. nov. (Rubiaceae); Alangium nepalensis sp. nov. (Alangiaceae); Homonoia lanceolata sp. nov. (Euphorbiaceae) and Ficus miocenicus sp. nov. (Moraceae). The modern counterparts of these fossils are mostly distributed in the tropical evergreen to semi-evergreen forests of Indo-Malayan region which indicate the existence of similar types of forests in the frontal Himalayan foot-hill zone during the Middle Miocene-Pliocene. The absence of tropical evergreen dipterocarps and their associates in the present-day flora of this region reflects changes in the annual mean temperature and rainfall caused by further uplift of the Himalayas and the northward movement of the Indian Plate.
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Poole, Imogen, and Helmut Gottwald. "Monimiaceae sensu lato, an element of Gondwanan polar forests: Evidence from the late Cretaceous-early tertiary wood flora of Antarctica." Australian Systematic Botany 14, no. 2 (2001): 207. http://dx.doi.org/10.1071/sb00022.
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Palaeofloristic studies of the Antarctic Peninsula region are important in furthering our understanding of (i) the radiation and rise to ecological dominance of the angiosperms in the Southern Hemisphere during the Late Cretaceous and (ii) the present day disjunct austral vegetation. Investigations of Upper Cretaceous and Early Tertiary sediments of this region yield a rich assemblage of well-preserved fossil dicotyledonous angiosperm wood which provides evidence for the existence, since the Late Cretaceous, of temperate forests similar in composition to those found in present-day southern South America, New Zealand and Australia. This paper describes two previously unrecognised morphotypes, which can be assigned to the Monimiaceae sensu lato, and represents the first record of this family in the wood flora of Antarctica. Specimens belonging to the first fossil morphotype have been assigned to Hedycaryoxylon SÜss (subfamily Monimioideae) because they exhibit anatomical features characteristic of Hedycaryoxylon and extant Hedycarya J.R.Forst. & G.Forst. and Tambourissa Sonn. Characters include diffuse porosity, vessels which are mainly solitary with scalariform perforation plates, opposite to scalariform intervascular pitting, paratracheal parenchyma, septate fibres and tall (>3 mm), wide multiseriate rays with a length: breadth ratio of approximately 1: 4. Specimens belonging to the second morphotype have been assigned to Atherospermoxylon KrÄusel, erected for fossil woods of the Monimiaceae in the tribe Atherospermeae (now Atherospermataceae) in that they exhibit anatomical features similar to Atherospermoxylon and extant Daphnandra Benth., Doryphora Endl. and Laurelia novae-zelandiae A.Cunn. These characters include diffuse to semi-ring porosity, scalariform perforation plates with up to 25 bars, septate fibres, relatively short (<1 mm) rays with a length: breadth ratio of between 1: 4 and 1: 11.
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Elkhawad, Mohamed, Amna Abdalla, and Abosofian Osman. "Weeds distribution and abundance in irrigated fields of White Nile State." International Journal of Environment 4, no. 4 (December 11, 2015): 45–61. http://dx.doi.org/10.3126/ije.v4i4.14098.
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Field survey was conducted during the summer season of 2011- 2012 to determine the weed flora and weed dominance at the irrigated sites of White Nile State. The State was divided into six irrigated sites from which a total of thirty- five fields were selected and ten quadrates (1m2) from each field were taken randomly. In each quadrate individual weed species were recorded. Field frequency, uniformity and mean field density were also determined for each weed. Fifty five weed species belonging to twenty- four families (three monocotyledonous and twenty- one dicotyledonous) were recorded. Brachiaria eruciformis, Brachiaria reptans, Thunbergia annua and Ipomoea cordofana were the most dominant weed species in most fields. The highest Abundance Index were recorded by Ipomoea cordofana at El Salam and El Dawium counties (208.16 and 116.35), Brachiaria eruciformis at Um Remta and El Gebalen counties (158.80 and 79.23), Brachiaria reptans at Kosti (116.54) and Momordica balsamina at Gezira Aba county (90.06). Brachiaria eruciformis showed the highest MFD and Uniformity at El Salam and Um Remta Counties (19.11 and 80.00), respectively, and highest frequency value was recorded by Ipomoea cordofana (142.86) at El Salam County. The AI which used as weed survey method is to evaluate the weed management strategies and the change of weed species in weed communities through years.International Journal of Environment Vol.4(4) 2015: 45-61
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Cevallos-Ferriz, Sergio R. S., and Ruth A. Stockey. "Permineralized fruits and Seeds from the Princeton chert (Middle Eocene) of British Columbia: Lythraceae." Canadian Journal of Botany 66, no. 2 (February 1, 1988): 303–12. http://dx.doi.org/10.1139/b88-050.
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Two types of lythraceous fruit and seed remains are described from the Middle Eocene, Allenby Formation of Princeton, British Columbia. Small globose, pedicellate fruits with persistent sepals, four to six locules, septa complete to the fruit apex, axial placentation, a palisade-like endocarp, and pyramidal seeds are referable to the genus Decodon Gmel. Numerous dispersed anatropous seeds of the same morphology show rounded or angular comers, lack lateral wings, and have a raphe that begins near the micropyle, passing through the middle integumentary layer on the dorsal face to the seed chalaza. Integuments are three zoned and seeds bear a ventral germination valve composed of radially elongated rectangular cells similar to the outer integumentary layer. Seeds show a prominent hypostase and dicotyledonous embryos with remains of a suspensor. These fruits and seeds are described as a new species of Decodon, D. allenibyensis Cevallos-Ferriz et Stockey sp.nov., which represents the oldest known species of the genus described to date. One fruit with several large, pyramidal lythraceous seeds is described. Seeds have three integumentary zones, the outer of which appears to have been mucilaginous. These remains most closely resemble the genus Lawsonia L., but additional specimens are needed to confirm this comparison. These lythraceous remains add to our knowledge of the Princeton angiosperm flora and further support the idea that these plants lived along a lake or marsh.
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Andruszczak, Sylwia, Piotr Kraska, Ewa Kwiecińska-Poppe, and Edward Pałys. "Biological diversity of weeds in a winter triticale (Triticum rimpaui Wittm.) crop depending on different doses of herbicides and foliar fertilization." Acta Agrobotanica 64, no. 2 (2012): 109–18. http://dx.doi.org/10.5586/aa.2011.022.
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A field experiment was conducted in the period 2006-2008 on incomplete podzolic soil. The present study investigated the effect of different doses of the herbicides Mustang 306 SE and Attribut 70 WG as well as of the foliar fertilizers Insol 3 and FoliCare 18:18:18 on the biodiversity of weeds in a winter triticale crop, 'Todan'. The segetal flora was assessed 6 weeks after the application of the herbicides and before the harvest of the triticale crop. The herbicides were applied together at labelled doses as well as at doses reduced to 75% and by half. Spraying with the foliar fertilizers was done twice during the growing period. Plots in which no herbicides or foliar fertilizers were used were the control treatment. <i>Matricaria maritima</i> and <i>Viola arvensis</i> from the dicotyledonous class were predominant in the winter triticale crop, whereas <i>Apera spica-venti</i> was the dominant species among the monocotyledons. The weed control efficacy of the reduced herbicide doses was weaker compared to the labelled rates by, respectively, from 6% to 9% at the first time of weed infestation assessment and from 4% to 8% at the second assessment time. Simultaneously, air-dry weight of weeds in the herbicide-treated plots did not differ significantly. This indicates that it is possible to reduce herbicide doses in a winter triticale crop without a risk of increased weed infestation .
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Sreena, K. S., G. S. Yadahalli, B. M. Chittapur, M. Y. Ajayakumar, S. N. Bhat, and Nagaraj Naik. "Significance of Weed Flora Identification and its Management on Bt Cotton (Gossypium hirsutum L.) Growing Tract of Tungabhadra Command Area." International Journal of Plant & Soil Science 35, no. 18 (July 25, 2023): 781–89. http://dx.doi.org/10.9734/ijpss/2023/v35i183374.
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Aims: To identify the weed species in Bt cotton under Tunga-bhadra project command area and to study the effect of sequential application of pre- emergent (PE) and post- emergent herbicides (PoE) on weed growth and to know the efficiency of different weed control practices on weed species.
Study Design: The experiment was laid in RBD (Randomized Block Design).
Place and Duration of Study: The experiment was conducted at ICAR- Krishi Vigyan Kendra farm, UAS, Raichur situated in TBP command area during kharif season of 2018-19.
Methodology: The design was RBD with 11 treatments and replicated thrice. Gross plot size of the field was 7.2 m × 4.8 m and net plot size was 5.4 m ×3.6 m with spacing of 90 x 30 cm. The certified seeds of Jadoo Bt II Cotton with the test weight of 6.5 g was used for sowing. The crop duration was around 6 month
Results: Weed flora present in the Bt cotton field were identified and classified based on their morphology. It was divulged that; dicotyledonous weeds were dominant in cotton field. The sequential applications of metolachlor 50 % EC @ 1000 g a.i. ha-1 as PE fb pyrithiobac sodium 10 EC @ 125 g a.i. ha-1 as PoE @ 2-5 leaf stage of weeds fb Inter cultivation (IC) @ 60 DAS reported lower weed count and weed dry matter and reported the highest weed control efficiency (90.22 %) at harvest than the application of diuron 80 % WP as PE fb @ 1500 g a.i. and pendimethalin Pendimethalin 30 EC @ 1250 g a.i. ha-1 as PE followed by pyrithiobac sodium 10 EC @ 125 g a.i. ha-1 as PoE @ 2-5 leaf stage of weeds fb Inter cultivation (IC) @ 60 DAS.
Conclusion: Application of pre-emergent followed by post emergent herbicides control the early and later flush of weeds. It avoids the emergence of broad spectrum weed flushes and weed shift. Integrated herbicidal application along with intercultural operations was found better in keeping weeds under a threshold than following a single method.
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Dor, E., R. Aly, and J. Hershenhorn. "Pomegranate (Punica granatum) as Host of the Broomrapes Phelipanche aegyptiaca and Orobanche crenata in Israel." Plant Disease 98, no. 6 (June 2014): 859. http://dx.doi.org/10.1094/pdis-10-13-1058-pdn.
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Orobanche and Phelipanche, commonly known as broomrape, are dicotyledonous holoparasitic flowering plants that cause heavy economic losses in a wide variety of plant species. Egyptian broomrape (Phelipanche aegyptiaca Pomel.) parasitizes more than 30 food and ornamental crops, including tomato, sunflower, tobacco, chickpea and many others in different parts of the world. Crenate broomrape (Orobanche crenata Forsk.) parasitizes important legume crops, such as lentil, faba bean, chickpea, pea, vetches, and grass pea, as well as some apiaceous crops, such as carrot (4). This is the first report of pomegranate (Punica granatum L.) as a new host for broomrape. This is also the first report of broomrape parasitism on a Lythraceae family member. Because of their high value for human health, the demand for pomegranate fruits has increased tremendously in the last few years and the extent of pomegranate growth has increased significantly in many regions throughout the world. In March 2013, heavy broomrape infection of a 10-year-old pomegranate orchard near the village Kfar Pines was reported. The infected area of about 2 ha was located in the middle of a big pomegranate orchard (variety 116). Broomrape inflorescence counts in the infected area revealed 14 and 0.6 P. aegyptiaca and O. crenata shoots per m2, respectively. Both broomrape species were uniformly distributed over all the infected area. No differences of infection rate between the pomegranate trees could be observed. The inflorescences of the two species were normal and healthy and produced germinable seeds. Digging up the inflorescences verified a direct connection between the parasites and the pomegranate roots. The parasite species were identified morphologically according to Flora Europea (2) and Flora Palaestina (3). Detailed description of the two parasites may be found in (4). Identification was confirmed using unique DNA marker based on the photosynthetic gene rbcL of O. crenata. rbcL primers were able to distinguish between the above two species according to differences in PCR products yielding 390 bp for P. aegyptiaca and 300 bp for O. crenata (1). This was the first time that broomrapes had appeared in the orchard since its establishment, on fields that had been intensively used for processing tomato. No legume cropping history in the infected areas is known. It may be hypothesized that the broomrape seeds were dormant in the soil for over 10 years (4).The extremely wet and hot weather conditions of winter 2012/13 induced their germination. A total of 730 mm of rainfall was measured for that year as compared to the annual average of 560 mm for the region. High-level infestations with P. aegyptiaca and O. crenata were also reported from two other pomegranate orchards, Givat Ada and Evron, 11 km west and 81 km north of Kfar Pines, respectively. Neither symptoms nor visible qualitative or quantitative damage could be observed on the infected vs. non-infected pomegranate trees. However, pomegranate appears to be an alternate host for P. aegyptiaca and O. crenata serving as a seed inoculum source for nearby sensitive field crops. References: (1) R. Aly et al. Joint Workshop of the EWRS Working Groups, 29 September – 3 October, Chania, Crete, Greece, 2013. (2) A. O. Chater and D. A. Webb. Orobanche. Page 285 in: Flora Europaea, Vol. 3. T. G. Tutin et al., eds. University Press, Cambridge, 1972. (3) N. Feinbrun-Dothan. Page 210 in: Flora Palaestina, Vol. 3. Israel Academy of Sciences and Humanities, Jerusalem, 1978. (4) D. M. Joel et al., eds. Parasitic Orobanchaceae: Parasitic Mechanisms and Control Strategies. Springer Verlag Berlin Heidelberg, 2013.
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Tialou, Oueuga Florence, Freddy Arnaud Yapi, Konan Kla, and Kama N’takpé Maxim Boraud. "Adventices majeures des parcelles industrielles de canne à sucre des unités agricoles intégrées en Côte d’Ivoire." International Journal of Biological and Chemical Sciences 15, no. 2 (June 22, 2021): 594–608. http://dx.doi.org/10.4314/ijbcs.v15i2.17.
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Cette étude vise à identifier les adventices qui constituent la flore des plantations industrielles de canne à sucre des Unités Agricoles Intégrées de Côte d’Ivoire. Elle a permis d’établir la liste des adventices majeures et de montrer leur degré d’infestation dans les exploitations de canne à sucre. Pour mener à bien ce travail, la méthodologie a constitué à faire des placettes de 1500 m2 (30 m x 20 m). Dans ces placettes, chaque espèce rencontrée est évaluée par sa présence et son indice d’abondance-dominance. Les familles majoritaires sont celles des Poaceae, des Asteraceae, des Fabaceae, des Euphorbiaceae et des Cyperaceae. La plupart des espèces sont des Dicotylédones avec 69 %, dominé par les Thérophytes avec une proportion estimée à 29 %. Les espèces d’adventices les plus nuisibles à la culture de la canne à sucre sont : Lactuca taraxacifolia ; Passiflora foetida ; Ipomoea triloba ; Calopogonium mucunoides ; Cyperus rotundus L. ; Cucumis melo L. var. agrestis ; Desmodium scorpiurus ; Merremia peltata ; Mucuna pruriens ; Mondia whitei ; Tridax procumbens ; Rottboellia cochinchinensis ; Trianthema portulacastrum ; Desmodium tortuosum. La connaissance des adventices majeures dans la culture de canne à sucre est la première étape pour la mise en oeuvre d’un itinéraire technique efficace de gestion des bioagresseurs.Mots clés : Adventices, Canne à sucre, Unités Agricoles Intégrées.
English Title: Major weeds of industrial sugar cane plots of integrated agricultural units in Côte d'Ivoire
This study aimed at identifying the weeds that make up the flora of industrial sugar cane plantations of the Integrated Agricultural Units of Côte d'Ivoire. It has made to establish the list of major weeds and to show their level of infestation in sugar cane farms. To carry out this work, the methodology used was to make plots of 1500 m² (30 m x 20 m). In these plots, each species encountered was evaluated by its presence and its abundance-dominance index. The majority families are those of Poaceae, Asteraceae, Fabaceae, Euphorbiaceae and Cyperaceae. Most species are Dicotyledonous with 69% dominated by Therophytes (29%). The most harmful adventitious species for the cultivation of sugar cane are: Lactuca taraxacifolia; Passiflora foetida; Ipomoea triloba; Calopogonium mucunoides; Cyperus rotundus L.; Cucumis melo L. var. agrestis ; Desmodium scorpiurus ; Merremia peltata ; Mucuna pruriens ; Mondia whitei ; Tridax procumbens ; Rottboellia cochinchinensis ; Trianthema portulacastrum ; Desmodium tortuosum. The determination of major weeds in sugarcane cultivation is the preliminary stage of effective fight against biological constraints.Keywords : Weeds, sugarcane, Integrated Agricultural
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Lagunova, Elena, and Olga Larina. "The taxonomy of higher vascular plants, lichens and fungi in the city of Abakan (Republic of Khakassia)." BIO Web of Conferences 38 (2021): 00069. http://dx.doi.org/10.1051/bioconf/20213800069.
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The flora of vascular plants in the city of Abakan (Republic of Khakassia, Russia) is represented by 459 taxa belonging to 69 families and 325 genera. Angiosperms are predominant in the flora of higher vascular plants and are represented by 451 species (98.3% of the entire city flora), including monocotyledons (104 species, 22.7%) and dicotyledons (347 species, 75.6%). According to these indicators, the flora of this city belongs to temperate floras of the Holarctic. The presence of 24 single-species families in the Abakan flora is related to the observed poor state of environment-forming factors, which prevents the adaptation of species under the new transformed conditions of the urbanized environment. Lichens in Abakan are represented by 33 species affiliated with 18 genera and 8 families. There are 125 mushroom species belonging to 75 genera, 34 families, 6 orders, and a single class, Agaricomycetes.
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Pakul, A. L., N. A. Lapshinov, V. N. Pakul, and G. V. Bozhanova. "Weed infestation of soft spring wheat crops depending on the soil tillage system." Siberian Herald of Agricultural Science 50, no. 3 (July 26, 2020): 16–27. http://dx.doi.org/10.26898/0370-8799-2020-3-2.
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The paper presents the results of the study on the influence of various tillage systems on the weed infestation of soft spring wheat of the Siberian Alliance variety. The study was carried out in a long-term stationary experiment (20152019) preceded by bare and green-manured fallow (rapeseed, melilot) in Kemerovo region. The soil of the experimental plot is classified as leached, medium-textured, medium-humus, heavy-loam chernozem. The following soil tillage systems were studied: deep moldboard, deep combined, minimum combined and minimum moldboard. Weather conditions during the research period were varied. Insufficient water supply during the first vegetation period of soft spring wheat (seedlings – leaf-tube formation) was noted in 2015-2017, with HTC (hydrothermal coefficient) being from 0.37 to 0.56. Excessive water content was observed in 2018 (HTC = 2.41) and moderate hydration – in 2019 (HTC = 1.12). Weed infestation was different in the conditions of each year. The impact of the soil tillage system on the number of weeds during the growing season of common spring wheat accounted for 21.6-90.4%, and their share in the total aboveground mass of the phytocenosis was 39.9-68.3%. The segetal flora in soft spring wheat crops is represented by monocotyledonous and dicotyledonous species with all the studied tillage systems. The highest density of weed vegetation during the tillering phase of soft spring wheat was recorded with deep moldboard soil tillage system (control). A reduction in weed infestation by 2.3 times compared to the control was noted with minimum moldboard soil tillage system preceded by bare fallow, 1.6 times – preceded by green-manured fallow with rapeseed, and 1.7 times – preceded by green-manured fallow with melilot. The same trend was observed in the proportion of weeds in the total aboveground mass of the phytocenosis during the wax ripeness phase of soft spring wheat with deep moldboard tillage system (4.3%), deep combined (3.9), minimum combined (4.1), minimum moldboard (2.6%).
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Bande, M. B., and G. P. Srivastava. "Late Cenozoic plant-impressions from Mahuadanr valley, Palamu District, Bihar." Journal of Palaeosciences 37, no. (1-3) (December 31, 1988): 331–66. http://dx.doi.org/10.54991/jop.1988.1632.
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Impressions of leaves, fruits and a flower have been described from the Late Cenozoic beds from near Mahuadanr, Palamu District, Bihar. The assemblage consists of 25 species belonging to 22 genera and 16 families of the dicotyledons. Family Asclepiadaceae and the genera Spondias, Erythrina, Combretum, Mitragyna, Alstonia and Cryptolepis have been described for the first time from the Cenozoic of India. The data have been used to decipher the palaeoecology and depositional environment of the region. A comparison of this flora with other Neogene floras of India has also been made.
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Boyce, Peter, and Hsuan Keng. "The Concise Flora of Singapore. Gymnosperms and Dicotyledons." Kew Bulletin 47, no. 1 (1992): 156. http://dx.doi.org/10.2307/4110786.
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MAURYA, LALITKUMAR L., OMKAR MOHAN HANDE, and VINAYAK K. PATIL. "Floral diversity of Dr. B. S. Konkan Krishi Vidyapeeth campus, Dapoli, Maharashtra." Journal of Farm Sciences 36, no. 03 (January 10, 2024): 300–311. http://dx.doi.org/10.61475/jfs.2023.v36i3.15.
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The study presents a checklist of the floral diversity of the College of Forestry campus, Dr. B.S. Konkan KrishiVidyapeeth, Dapoli, Ratnagiri, Maharashtra. In the present study total 384 taxa from 102 families, 284 genera wereidentified and checklist was prepared. These floras are categorized into different life forms representing 112 tree species, 40shrub species, 165 herbs, 58 climbers, and 9 ferns. These plants were again divided into dicotyledons, which representabout 311 species, monocots with 64 species, and nine pteridophytes. An attempt was also made to highlight some of thethreatened key plant species available in the campus.
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Марченко, А. Б. "Декоративні квіткові рослини в структурі урбофлори Лісостепу України." Вісник Полтавської державної аграрної академії, no. 1-2 (September 30, 2016): 36–43. http://dx.doi.org/10.31210/visnyk2016.1-2.07.
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За результатами моніторингу флористичного різноманіття декоративних квіткових рослин у структурі озеленення урбоекосистем Лісостепу України уточнено їх таксономічний склад, а саме представлені 118 видами із 58 родів 31 родини 16 порядків 2 класів. Домінуюче місце займає клас Dicotyledones, який представляє 66,1 %, налічує 14 порядків, серед яких за кількістю видів переважає Asterales – 34 % видів. Клас Liliopsida представлений двома порядками, серед яких за кількістю видів переважає Asparagales Bromhead (70 %). За класифікацією І. Г. Серебрякова декоративні квіткові культури представлені наземними трав’яними (98,8 %), деревними життєвими формами (1,2 %), які в свою чергу представлені монокарпічними (71 %) та полікарпічними травами (27,8 %), кущами (1,2 %). За класифікацією X. Раункієра, декоративні квіткові культури представлені життєвими формами: терофіти (71 %), криптофіти (27,8 %),фанерофіти (1,2 %). За екологічними показниками всі наземні рослини відносно до вологи поділяються на мезофіти (52 %), ксеромезофіти (24 %), ксерофіти (21 %), мезогігрофіти (3 %); відносно до інтенсивності освітленості – геліофіти (81 %), сциофіти (19 %).
According to the results of monitoring of the floristic diversity of ornamental floral plants in the structure of urban ecosystems’ greenery of Forest-Steppe zone of Ukraine we have clarified their taxonomic composition. Decorative floral plants in the structure of urban flora are presented by 118 species from 58 genera 31 families 16 orders of 2 classes. Dicotyledones class dominates in terms of quantity, representing 66,1 %, and the Liliopsida class represents 33,9 % of species. Dicotyledones class numbers 14 orders, in which Asteralesorder occupies a dominant place on the number of species (34 % of species), other orders of Saxifragales Dumort are represented by 13 %, Brassicales Bromhead – by 8,9 %, Ericales – by 7,6 %, Lamiales Bromhead, Rosales – by 6,4 %. Other orders are represented by 1–2 species. Liliopsida class is represented by two orders, among which Asparagales Bromhead dominates in terms of the number of species (70 %). According to the classification by I. G. Serebryakov, decorative floral plants are represented with herbal terrestrial plants (98,8 %), tree life forms (1,2 %), which are represented with monocarpic (71 %) and polycarpic herbs (27,8 % ), shrubs (1,2 %). According to the classification by H. Raunkiyer, decorative floral crops are represented by the following forms: therophytes (71 %), cryptophytes (27,8 %), tall aerial plants (1,2 %). According to all environmental indicators, in terms of moisture, all terrestrial plants are divided into mesophytes (52 %), xeromesophytes (24 %), xerophytes (21 %), mesohygrophytes (3 %); in terms of light intensity – heliophytes (81 %), sciophytes (19 %).
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Dornelas, Marcelo C., and Adriana P. M. Rodriguez. "A genomic approach to elucidating grass flower development." Genetics and Molecular Biology 24, no. 1-4 (December 2001): 69–76. http://dx.doi.org/10.1590/s1415-47572001000100011.
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In sugarcane (Saccharum sp) as with other species of grass, at a certain moment of its life cycle the vegetative meristem is converted into an inflorescence meristem which has at least two distinct inflorescence branching steps before the spikelet meristem terminates in the production of a flower (floret). In model dicotyledonous species such successive conversions of meristem identities and the concentric arrangement of floral organs in specific whorls have both been shown to be genetically controlled. Using data from the Sugarcane Expressed Sequence Tag (EST) Project (SUCEST) database, we have identified all sugarcane proteins and genes putatively involved in reproductive meristem and flower development. Sequence comparisons of known flower-related genes have uncovered conserved evolutionary pathways of flower development and flower pattern formation between dicotyledons and monocotyledons, such as some grass species. We have paid special attention to the analysis of the MADS-box multigene family of transcription factors that together with the APETALA2 (AP2) family are the key elements of the transcriptional networks controlling plant reproductive development. Considerations on the evolutionary developmental genetics of grass flowers and their relation to the ABC homeotic gene activity model of flower development are also presented.
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Dzomeku, I. K., M. Abudulai, R. L. Brandenburg, and D. L. Jordan. "Survey of Weeds and Management Practices in Peanut (Arachis hypogaea L.) in the Savanna Ecology of Ghana1." Peanut Science 36, no. 2 (July 1, 2009): 165–73. http://dx.doi.org/10.3146/ps08-009.1.
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Abstract Peanut (Arachis hypogaea L.) is the most popular legume cultivated for food and cash in the Guinea and Sudan savannah ecologies of northern Ghana. A three-year survey was conducted between 2003 and 2005 to: (1) document the prevalence of weed species, (2) determine current cropping systems and weed management practices, and (3) assess the response of peanut to weed management practices. Flora with more than 5% dominance included: (1) the dicotyledonous weeds, Corchorus olitorius L. Commelina benghalensis L., Commelina diffusa Burm., f, Desmodium scorpluras (Sw.) Desv., Hyptis suoveolens Poit., Mimosa invisa Mart., Mimosa pigra L., Mitracarpus villosus (Sw.) DC., Oldenlandia corymbosa L., Phyllanthus amarus Schum. & Thonn., Scoparia dulcis L., Tridax procumbens L., Triumfeta cordiflora A. Rich., and Vernonia galamensis (Cass.) Less.; (2) the monocotyledonous weeds Axonopus compresus (Sw.) P. Beauv., Cyperus esculentus L., Cyperus rotundus L., Digitaria horizontalisWilld., Eragrostis tremula Hochst. Ex Steud., Hackelochloa granularis (L.) O. Ktze., Kyllinga erecta Schumach. Var., Kyllinga squamulata Thonn. Ex Vahl., Paspalum scrobiculatum L., Rottboellia cochinchinensis (Lour.) Clayton, and Setaria pallide-fusca (Schum.) Stapf. & C.E. Hubbard; and (3) the parasitic weed Striga hermonthica (Del.) Benth. Land preparation practices included the use of tractors, followed by use of livestock, and lastly hand preparation. Cropping systems consisted of cereals preceding peanut, peanut preceding peanut, and intercropping peanut with sorghum (Sorghum bicolor L. Moench.), millet (Pennisetum Americanum L.), or corn (Zea mays L.). Genetically-improved peanut cultivars expressing bunch or erect growth habits were the most common cultivars although some farmers planted local cultivars expressing a distinct runner growth habit. The majority of farmers planted peanut from early June to early July based on rainfall pattern. Eighty-eight percent of peanut fields were hand weeded once, 3 to 5 weeks after planting (WAP) or twice, 2 to 3 and 5 to 6 WAP. Weed management was generally poorly timed and insufficient to prevent significant weed interference resulting in total oven-dried weed biomass ranging from 600 to 2400 kg/ha at harvest. Peanut haulm production ranged from 500 to 5500 kg/ha with improved cultivars. Pod yield production ranged from 200 to 1680 kg/ha. Results from this survey revealed the need for accelerated research and capacity building of farmers and agricultural extension agents for improved technology transfer to the peanut industry in the region.
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Renukarya, C. K., H. N. Krishna Kumar, and Jyoti Bala Chauhan. "Studies on the flora of Mahajana PG campus." Journal of Scientific and Innovative Research 4, no. 5 (October 25, 2015): 207–12. http://dx.doi.org/10.31254/jsir.2015.4504.
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In the present investigation, a total of 152 species representing 131 genera belonging to 55 families have been recorded. Among these, 43 families, 99 genera and 118 species are dicotyledons. The monocotyledons represent 9 families, 32 genera and 34 species. The genus species ratio is 1:1.2 and the ratio of monocotyledons to dicotyledons is 1:3.5. Of the 55 families collected, the most dominant family is Euphorbiaceae with 13 species. In the collected 131 genera 17 are dominant with more than 2 species. The availability and distribution of individual plant species has been scrutinized carefully for its future sustainable utilization. The study found that majority of the plants recorded from the campus area are having medicinal value.
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Arditti, Joseph, S. M. Walters, J. C. M. Alexander, A. Brady, C. D. Brickell, J. Cullen, P. S. Green, et al. "The European Garden Flora. Vol. III. Dicotyledons (Part I)." Bulletin of the Torrey Botanical Club 118, no. 2 (April 1991): 216. http://dx.doi.org/10.2307/2996873.
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Schmid, Rudolf, N. G. Walsh, and T. J. Entwisle. "Flora of Victoria. Vol. 4. Dicotyledons: Cornaceae to Asteraceae." Taxon 49, no. 2 (May 2000): 344. http://dx.doi.org/10.2307/1223869.
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Coca-Salazar, Alejandro, Huber Villca, Mauricio Torrico, and Fernando D. Alfaro. "Plant communities on the islands of two Altiplanic salt lakes in the Andean region of Bolivia." Check List 12, no. 5 (October 4, 2016): 1975. http://dx.doi.org/10.15560/12.5.1975.
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This paper reports a quantitative survey of the composition, diversity and structure of the plant communities on six islands of Uyuni and Coipasa salt lakes (Bolivia). Plant communities on each island were examined via the use of 10 transects, along which species richness and abundance were recorded. Seventy-one species were found in total, representing pteridophytes (6%), gymnosperms (1%), monocotyledons (14%) and dicotyledons (79%). About 21% of the species were endemic or faced some degree of threat. The calculation of Shannon-Wiener α-diversity indices and comparisons of community structure revealed similarities between the islands. Indeed these analyses suggest the existence of a single floral assemblage; however, small differences in the plant communities were visually identified during fieldwork. These islands are home to a considerable subset of the Altiplano’s flora and appear to have been little disturbed. They should therefore be the subject of surveillance/conservation programs.