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1.
The chromosome cytology of Hyacinthaceae subfamily Ornithogaloideae is reviewed within the framework of a recent molecular-based classification, with particular emphasis on its center of diversity in sub-Saharan Africa. We also provide new chromosome counts for sections that are unknown or poorly known cytologically. Albuca subgen. Namibiogalum (9 spp.) probably has an ancestral base number of x = 10 but subgen. Albuca (± 70 spp), subgen. Monarchos (9 spp.) and subgen. Osmyne (36 spp.) have x = 9. The pattern in subgen. Urophyllon (3 spp.) is remarkable: although x = 6 is likely, the species in the section exhibit a range of 2n = 12, 10, 8, 6 and 4 (exclusive of polyploidy). All karyotypes have three large chromosome pairs and a variable number of small chromosomes. Pseudogaltonia (2 spp.) has x = 9 and Dipcadi (26 spp.) possibly x = 9 in series Uropetalum and x = 6 in series Dipcadi, which exhibits a pattern of descending dysploidy leading to n = 3 in D. marlothii. In Ornithogalum (± 130 spp.) chromosome numbers are known for only 24 of the ± 84 sub-Saharan species, mostly from subgen. Aspasia and subgen. Ornithogalum sect. Linaspasia, both of which have x = 6, and from subgen. Galtonia, which has x = 8. In contrast, x = 7 is basic for the Eurasian sects. Honorius and Melophis, and x = 18 seems likely for sect. Cathissa. Sect. Ornithogalum, the cytology of which we does not examine in detail, may have x = 9. Polyploidy is apparently rare in the sub-Saharan African ornithogaloids, in marked contrast to the high frequency of polyploidy among Eurasian species. In Albuca just 3 or possibly 4 sub-Saharan species (9% or 13% of those counted) are exclusively polyploid and 5 more have diploid and polyploid races; and in sub-Saharan Ornithogalum, only the tropical O. gracillimum is exclusively polyploid, and the western southern African O. hispidum has diploid and polyploid races.  相似文献   

2.
V. Sh. Agababian 《Grana》2013,52(3):166-176
The pollen morphology of the following genera is described: Manglietia (1 sp.), Magnolia (10 spp.), Talauma (2 spp.), Alcimandra (1 sp.), Michelia (5 spp.) and Liriodendron (2 spp.). It is shown that from a pollen morphological point of view the Magnoliaceae are a homogeneous, natural group.  相似文献   

3.
Benomyl (0.025% a.i.) and thiabendazole (0.05 % a.i.) applied in July, August and September to apple trees cvs. Sunset and Cox's Orange Pippin gave slightly better control of Gloeosporium spp. rots in stored fruit than captan (0.1% a.i.) applied at similar intervals. On Cox's Orange Pippin, treatment with captan at 0.1 % a.i. in July and at 0.2% a.i. in August was as effective as three sprays at 0.1 % a.i. in July, August and September in controlling both Gloeosporium spp. and Nectria galligena rots. Benomyl applied in the spring and early summer to control apple scab on orchard trees reduced the incidence of Gloeosporium spp. and Monilia fructigena in stored fruit. Pre-harvest sprays of benomyl and captan gave good control of rotting caused by N. galligena but thiabendazole was ineffective. Post-harvest dips of thiabendazole controlled rotting by Gloeosporium spp. butnot byN. galligena.  相似文献   

4.
Marcus Lehnert 《Brittonia》2006,58(3):229-244
A summary is presented of all Bolivian species of Cyatheaceae and Dicksoniaceae. In total two species of Dicksoniaceae (Culcita 1 sp.,Dicksonia 1 sp.) and 34 species of Cyatheaceae (Sphaeropteris 1 sp.,Alsophila 5 spp.,Cyathea 26 spp.,Cnemidaria 2 spp.) are known. One hybrid inCyathea is recognized. The endemicCyathea dintelmannii is newly described, andCyathea herzogii from Bolivia and Peru is separated fromCyathea caracasana var.boliviana. Both species are illustrated. An artificial key to the Bolivian species of Cyatheaceae is provided.  相似文献   

5.
A high-resolution biostratigraphic analysis of planktic foraminifers confirms that the Bidart section at the eastern margin of the Atlantic Ocean exhibits a continuous and complete Cretaceous/Paleogene (K/Pg) transition interval. The biozones and subzones recorded in this section are less expanded than their equivalent in Tunisian sections: El Kef (Global Stratotype Section and Point: GSSP for the K/Pg boundary) and Ellès (auxiliary section), but they are sufficiently thick to allow a detailed analysis of the evolution of the planktic foraminiferal assemblages across the K/Pg transition.Throughout the uppermost 4 m Maastrichtian, the planktic foraminiferal assemblages are highly diversified, containing up to 72 species. These Maastrichtian assemblages are rich in cosmopolitan taxa (70%), dominated by small biserial morphotypes which belong mainly to the genus Heterohelix which coexist with less abundant but highly diverse tropical and subtropical species.The extinction pattern at the Bidart section suggests a sudden catastrophic mass extinction at the K/Pg boundary which affected at least 53 out of 72 species. The species becoming extinct include globotruncanids (e.g. Contusotruncana spp., Globotruncana spp., Globotruncanita spp.) and complex heterohelicids (e.g. Racemiguembelina spp., Pseudotextularia spp., Gublerina spp.). At the Bidart section, only Archaeoglobigerina cretacea disappears 2 m below the K/Pg boundary event. Specimens of 18 small and even tiny Maastrichtian species, are found at the lowermost Danian. Only a few of these species belonging to the genera of Guembelitria, Hedbergella and Heterohelix are considered to be real “Cretaceous survivor species”, whereas the specimens belonging to the rest, are most probably reworked, because they differ in their preservation.Throughout lowermost Danian, the planktic foraminiferal assemblages are dominated by “opportunistic” species of the genus Guembelitria. These opportunists are associated to small and poorly diversified pioneer globigerinids (Palaeoglobigerina spp. and Parvularugoglobigerina spp.). These assemblages became progressively more diversified across the early Danian containing species with cancellate walls (Eoglobigerina spp., Parasubbotina spp., Subbotina triloculinoides and Praemurica spp.) and new taxa of biserial heterohelicids (Woodringina spp. and Chiloguembelina spp.) suggesting a paleoenvironmental recovery.  相似文献   

6.
Based on the melissopalynology 38 honey samples collected in the central region of the Argentine province of Entre Ríos were classified by botanical and geographical origin. According to qualitative analysis, 20 honey samples were monofloral and 18 were multifloral. Dominant pollen types were Scutia buxifolia Reissek (Rhamnaceae) in six samples, Baccharis spp. (Asteraceae) in five, Lotus spp. (Fabaceae) in three, Eucalyptus spp. (Myrtaceae) and Eryngium spp. (Apiaceae) in two, Ammi visnaga (L.) Lam. (Apiaceae) and Trithrinax campestris (Burmeist.) Drude & Griseb. (Arecaceae) in one sample. One hundred and nineteen pollen types were identified belonging to 52 families; 75% of which were native species. The families best represented in number of species were Asteraceae and Fabaceae. Pollen types such as Scutia buxifolia, Trithrinax campestris, Schinus spp. (Anacardiaceae), Mimosoideae from Prosopis spp., Acacia spp., Mimosa ostenii Speg. ex Burkart, and M. strigillosa Torr. & A. Gray are considered the indicators for this geographical origin. The studied honeys were also characterized by a high frequency of Apiaceae, Brassicaceae, Astereae, Echium plantagineum L. and cultivated Papilionoideae forage species such as Melilotus albus Desr., Lotus spp. and Trifolium spp. Honeydew elements were scarce.  相似文献   

7.
8.
Sylvia Feuer 《Grana》2013,52(4):225-242
This is the first of two papers detailing pollen morphology and evolution with the tribe Embothrieae comprising eight genera and ca. 56 spp. The present paper examines pollen of subtribes Buckinghaminae (Buckinghamia; 2 spp., Opislhiolepis; 1 sp.), Stenocarpinae (Strangea; 3 spp.), Stenocarpus (ca. 27 spp.) and Lomatiinae (Lomatia; ca. 12 spp.) in the light microscope and scanning and transmission electron microscopes. Pollen is medium-sized, oblate, foveolate to microreticulate to reticulate, and predominantly columellate with a complex modified postvestibulate aperture morphology. Pollen data indicate ties between Lomatia and Stenocarpus on the one hand and Stenocarpus and Strangea on the other. Though Buckinghamia and Opislhiolepis have been placed in the same subtribe, the unique combination of pollen features in each suggests only a remote relationship to each other as well as to remaining Embothrieae. Comparisons to the remaining genera of Embothriae (Embothrium, Oreocallis, Telopea) and overall analysis of pollen evolution within the tribe are detailed in the subsequent paper.  相似文献   

9.
The species composition, distribution and abundance of the Tubificidae (8 spp.) and Naididae (at least 4 spp.) in the Guangzhou reach of the Lower Pearl River were investigated. Limnodrilus spp. (particularly L. hoffmeisteri) constitutes the greatest part in nearly all samples, which were taken in both clean and polluted parts of the reach. In the polluted sites, total oligochaete densities reach values of up to 700 000 ind. m–2. The importance and problems of using oligochaetes as indicators of organic pollution are discussed.  相似文献   

10.
The predominant fungi present in samples of reject and retail red kidney beans were Aspergillus glaucus, Penicillium spp. and Alternaria spp. Together with A. ochraceus, A. flavus, Fusarium spp., and Trichoderma, these isolates from the reject beans were screened for numerous mycotoxins by TLC. The most consistently produced mycotoxins were penicillic acid (from A. ochraceus and Penicillium spp.) and Alternaria toxins (tenuazonic acid and alternariol). A. glaucus strains were tested for cytotoxicity in three tissue culture cell lines with positive results.  相似文献   

11.
The relationship between sediment trace metals (Ag, Cd, Cr, Cu, Ni, Pb, Zn) and bioaccumulation in tissue of macrobenthos (Parvilucina tenuisculpta, Tellina spp., Macoma spp., Pectinaria californiensis, Nephtys spp., Glycera spp., Metasychis sp., Euphilomedes spp., and Ampelisca spp.) was described from 1975 to 1985 on the San Pedro Shelf, California. Results indicated that: 1) sediment trace metals were elevated at an ocean outfall station; 2) tissue trace metals were never statistically higher at the outfall compared to a reference station except for Zn in Macoma spp.; 3) there were a few statistically significant associations (r) between tissue and sediment metals, but no consistent trends emerged; 4) peak tissue metal concentrations occurred more frequently in the winter than in the summer.  相似文献   

12.
Physical constrains such as water discharge, suspended solids and turbidity act as dominant factors in driving the planktonic diatom assemblages of the River Adige (North-Eastern Italy). Two sampling stations, characterised by different hydromorphological features (Cortina all’Adige and Boara Pisani, with torrential and more potamal characteristics, respectively) were sampled fortnightly following an integrated approach encompassing physical, chemical and biological measurements and aiming at identifying the dominant factors controlling the temporal development of the community. A morpho-functional approach was used to classify the diatom assemblages where Morpho-Functional Diatom Groups (MFDG) were defined for diatom genera, according to their morphology, habitat selection and modality of adhesion to river substrate. In the two sampling points, algal growth was never limited by nutrients or zooplankton. The irregular development of MFDG was determined by the stochastic hydrological events and changes in variables related to water discharge (suspended solids and light attenuation). Tychoplanktonic, benthic and drifted taxa (such as Diatoma spp., Encyonema spp., Navicula spp. and Nitzschia spp.) were dominant in the torrential station (Cortina all’Adige), while the contribution of euplanktonic unicellular centric taxa (such as Cyclotella spp., and Stephanodiscus spp.) was higher in the potamal station (Boara Pisani).  相似文献   

13.
Fungal (Aspergillus and Penicillium spp.) and yeast (Saccharomyces and Candida spp.) cultures were more sensitive to cumin volatile oil and cuminaldehyde than bacteria. Among Gram-negative bacteria, Escherichia coli was the most sensitive to the volatile oil while Pseudomonas aeruginosa was the most resistant. Staphylococcus aureus had an MIC almost double that of all other Gram-positive species tested, while the fungi had MIC values 10 to 20 times lower than those of the bacteria.The authors are with the Food & Fermentation Technology Division, University Department of Chemical Technology, Matunga, Bombay-400019, India  相似文献   

14.
The dock plant (Rumex spp.) is one of the most problematic pasture weeds worldwide. Allantus luctifer was selected as a potential biological control agent for Rumex spp. Continuous rearing of A. luctifer was carried out from 2005 to 2006, and its general biology is presented in this report. The preliminary host specificity test showed a promising result for using A. luctifer to control Rumex spp.  相似文献   

15.
Parasites and predators of the hemipteran superfamily Pyrrhocoroidea are compiled from the literature, and their relationship with their hosts discussed. The impact of the predacious bugs,Phonoctonus spp., on populations of cotton stainers (Dysdercus spp.) is evaluated; a rearing and release program is recommended.   相似文献   

16.
No previous studies have been conducted on the diversity and population of arbuscular mycorrhizal fungi (AMF) in relation to organically grown chili (Capsicum frutescens L.) in Thailand. This study was carried out to investigate the diversity and status of AMF populations at four organically managed farms in Ubon Ratchathani and Sisaket provinces. The effects of each AMF species on the growth and nutrient uptake of chili grown in sterile, organically managed soil were determined. Fourteen AM fungal taxa belonging to the genera Acaulospora (4 spp.), Entrophospora (1 sp.), Glomus (7 spp.) and Scutellospora (2 spp.) were found. Among these, Glomus was the dominant genus found at all sites, followed by Acaulospora. The spore density and root colonization of AMF on chili did not vary significantly among the sites. The effects of ten selected AMF species on the growth of chili showed that Gl. clarum RA0305 increased the growth, flowering, and fruit production of chili, and also increased the P uptake significantly, compared to non-mycorrhizal plants. This fungus showed the highest potential as a promoter of growth, flowering and yield in organically managed chili production.  相似文献   

17.
Foran  Jeffery A.  King  Robert H. 《Hydrobiologia》1982,94(3):237-246
The population dynamics of a planktonic rotifer (Polyarthra vulgaris) were examined in a brown water, acid lake in northern Michigan, U.S.A. Predation by Chaoborus punctipennis and low food (Navicula spp. and Cyclotella spp.) concentrations were the main factors limiting P. vulgaris populations of all factors examined. The data presented here support a hypothesis for zooplankton limitation by an invertebrate predator.  相似文献   

18.
The sugar and osmophilic fungal composition of soils amended with five organic substrates (newspaper, orange peel, bromegrass leaves, wheat straw and wood sawdust) was estimated after 2, 4, 6, 8 and 10 weeks using the dilution plate method on glucose and 50% sucrose Czapek's agar media. Wheat straw was the best substrate for total counts of both sugar and osmophilic fungi followed by newspaper, bromegrass leaves, wood sawdust and orange peel. Wood sawdust supported the highest average counts of total sugar fungi, Fusarium, Mucor, Scopulariopsis, Trichoderma and Trimmatostroma spp.; Newspaper, of Aspergillus (8 spp.), Penicillium (4 spp.) and Chaetomium sp. bromegrass leaves of Cladosporium sp., Humicola sp. and Sporotrichum sp.; orange peel, ofAlternaria sp., Circinella sp. and Stachybotrys sp.; and wheat straw, of Botryotrichum sp. and Myrothecium sp. Bromegrass leaves and orange peel supported the highest average counts of total osmophilic fungi, Aspergillus (10 spp.), Cladosporium sp. Paecillomyces sp. and Rhizopus sp.; and of Stemphylium sp., Trichoderma sp., Humicola sp. and Circinella sp. respectively; wheat straw, of Epicoccum sp., Scopulariopsis sp. and Trichothecium sp.; newspaper, of Penicillium (4 spp.) and Alternaria sp.; and wood sawdust of Curvularia sp. and Fusarium (3 spp.). The best colonizers throughout the experimental periods were Aspergilus and Penicillium spp.  相似文献   

19.
Fusarium root rot (Fusarium spp.) is one of the most important seedling diseases of coneflower (Echinacea spp.) in Alberta greenhouses. Effects of microbial antagonists (Trichoderma spp.) and fungicides, including difenoconazole, fludioxonil, and a mixture of fludioxonil, metalaxyl and difenoconazole, on the management of this disease, were investigated in Alberta. Twenty Trichoderma isolates demonstrated antagonistic activity to Fusarium in agar plate bioassays, with inhibition rates ranging from 44 to 65%. Some Trichoderma isolates significantly ( p < 0.05) reduced disease incidence and severity on seedlings in greenhouse experiments. An in vitro bioassay indicated that difenoconazole and the mixture equally inhibited the growth of both Fusarium and Trichoderma, but, while fludioxonil strongly inhibited the growth of Fusarium, it had little effect on Trichoderma, according to the dose--response models developed ( p < 0.01, R2= 0.902-0.998). Two Trichoderma isolates, T1 and T13 were applied singly or in combination with a low rate of fludioxonil in greenhouse evaluations. The results suggested that fludioxonil and Trichoderma could be integrated into a disease management program for fusarium root rot in coneflower.  相似文献   

20.
Air-borne fungi at Doha, Qatar   总被引:3,自引:3,他引:0  
Thirty-five genera and 73 species, were identifiedfrom 312 daily exposures set up during theperiod March 1997–March 1998. The total fungalcatch exhibited two peaks in July and December1997 and a trough in February 1998. Cladosporium (6 spp. 40.1% of total fungi),Alternaria (4 spp., 21%) andUlocladium (4 spp., 9.2%) were the maincomponents of air-borne fungi, and thecommonest species were Cladosporium.sphaerospermum (29.7%), C.cladosporioides (6.9%), Alternaria.alternata (13.9%) and U. atrum (5%).The predominance of these dark-coloured fungiin air is discussed and is attributed to one orboth of two hypotheses. Aspergillus (9spp., 4.3%) and Penicillium (8 spp.,3.95%) came next and were represented mainlyby A.niger (1.3%) andP. chrysogenum (2.4%).Spore showers of C.cladosporioides, C. sphaerospermum, Penicillium chrysogenum and Myrotheciumverrucaria were noticed with no regularseasonal pattern.The monthly number of species ranalmost parallel to the total count of fungi.The broadest species spectrum (25–29 spp.) wasrecorded in the summer months May–August 1997and the narrowest (11–12 spp.) in February andMarch 1998.The highest monthly wind velocity wasregularly associated with higher fungal colonycounts than in case of the lowest velocity. Onthe other hand, wind direction did not exhibitany regular correlation either with the colonycounts of fungi or with the wind velocity. Highwind velocity could bring more fungal spores tobe sedimented on the surface of exposed agar.Diurnal fluctuations of fungal spores offungi displayed one peak at 12 noon when thehighest temperature and wind velocity, and theleast relative humidity were recorded and onetrough at midnight.  相似文献   

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