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1.
Lonchocarpus castaneifolius, L. grazielae, L. longiunguiculatus, and L. montanus from Brazil are described and illustrated based on field and herbarium studies. The first species belongs to Lonchocarpus sect. Punctati and is restricted to northeastern Brazil (Bahia state). The other three are included in sect. Laxiflori. Lonchocarpus grazielae is restricted to the southern coastal region (Santa Catarina state), L. montanus is found in northeastern Brazil (Bahia and Piauí states), the west-central region (Goiás and Tocantins states) and the southeast (Minas Gerais state), and L. longiunguiculatus occurs in northeastern (Bahia state) and southeastern (Minas Gerais state) Brazil.  相似文献   

2.
Lantana camara is a poisonous, bushy shrub from South and Central America that has invaded much of the moist, warm sub-tropical areas of South Africa. In the last decade, evidence of a conspicuous and damaging mycobiota on lantana in the Neotropics has persuaded biocontrol researchers to consider fungi as potential biocontrol agents for this plant. Samples of diseased L. camara leaves were collected during field surveys in South, North and Central America from 1987 to 1997. Pathogenicity tests showed the leaf spot fungus, Mycovellosiella lantanae var. lantanae to be a promising biocontrol pathogen. Inoculations onto South African biotypes of L. camara and a number of closely related species within the family Verbenaceae were made under quarantine conditions to determine the pathogenicity and host specificity of the fungus. Inoculation of L. camara biotypes resulted in necrotic, grey lesions (20-60 per leaf), necrosis of flower buds and stalks, as well as defoliation of certain biotypes after three weeks. None of the other plant species tested showed any disease symptoms. This indicates a very restricted host range, making this pathogen a suitable candidate for application as a biological control agent. It is expected that the fungus will reduce the vigour and reproductive potential of L. camara. Due to the variation in virulence of M. lantanae var. lantanae when tested on South African lantana biotypes, release strategies may include the use of combinations of the isolates to target a wider range of lantana biotypes in the field. Permission to release M. lantanae var. lantanae in South Africa was granted in September 2001. The pathogen will be released as a classical biocontrol agent in South Africa.  相似文献   

3.
J-R. Baars  F. Heystek 《BioControl》2003,48(6):743-759
A survey was conducted todetermine the present status of five biocontrolagents established on Lantana camara L.(Verbenaceae) in South Africa. Three ofthe five agents, Calycomyza lantanae(Frick), Ophiomyia lantanae Froggatt andTeleonemia scrupulosa Stål areestablished throughout the range of L.camara. The two hispine beetles, Octotomascabripennis Guérin-Ménevilleand Uroplata girardi Pic are restrictedto the warm, subtropical regions in the easternrange of the weed, and are unable to cope withthe plants becoming seasonally leafless in dryand temperate areas. The two beetles and T. scrupulosa are rated as the most damagingagents on L. camara. The impact of O. lantanae is uncertain, and due to lowpopulations, the impact of C. lantanae isnegligible. Insect populations typicallyaccumulate to maximise their impact on plantsby midsummer, giving plants the opportunity tocompensate for the cumulative agent damageaccrued at the end of the previous growingseason. A number of parasitoids were rearedfrom U. girardi, O. lantanae andC. lantanae, but only those adapted toC. lantanae are expected to significantlyreduce its field density. The agents feed anddevelop on a wide range of lantana varieties,and where two or more varieties co-exist,insects occurred in equal abundance on thedifferent varieties. The importance of varietalpreferences appears to have beenover-estimated, but needs consideration whennew candidates are evaluated. The impact ofthese biocontrol agents is insufficient toreduce L. camara to a manageablesituation, and additional candidates arenecessary to control this weed in South Africa.  相似文献   

4.
Collections of natural enemies of Bemisia tabaci biotype B (Genn.) (Hemiptera: Aleyrodidae) were made in Lavras, state of Minas Gerais, Brazil. In the greenhouse, 6,495 predators and 16,628 parasitoids belonging to three families were collected. In the field, 267 predators and 344 parasitoids belonging to five families were found. For the first time in Brazil, five species of predators associated with this whitefly were reported. Because of the diversity of natural enemies of B. tabaci biotype B recorded, this study points out the importance of these data for studies on integrated pest management.  相似文献   

5.
Rosana Romero 《Brittonia》2000,52(2):142-144
A new species of the genusMicrolicia,M. flava, from the highland “campo rupestre” vegetation of Serra da Canastra National Park, São Roque de Minas, Minas Gerais, Brazil, is described and illustrated.  相似文献   

6.
A biotype of the flower-galling mite, Aceria lantanae (Cook) (Trombidiformes: Eriophyidae) collected in Florida (U.S.A.) was released in South Africa in 2007 against Lantana camara L. (Verbenaceae) but has displayed patchy establishment. The occurrence of different L. camara varieties and their susceptibility to A. lantanae were assessed across four provinces with dense infestations. Surveys were undertaken at 113 sites during the mite’s peak infestation period (April–May) in 2013–2015. The occurrence of 13 recorded L. camara varieties differed substantially across and within these provinces. Overall, five varieties accounted for 7–45% of the sampled plants at 9–51% of the surveyed sites. The remaining eight varieties accounted for <1–4% of the plants at 2–9% of the sites. The establishment and impact of A. lantanae differed significantly between L. camara varieties. The mite established best on three varieties (163 LP, 021 WP and 015 OR), with 60–90% of plants infested. Reduced establishments were observed on seven varieties, with 18–50% of plants infested, while no establishment was recorded on three varieties. Where established, A. lantanae inflicted considerable levels of damage (i.e. 51–75% of buds infested) on the most widespread and abundant L. camara variety (163 LP) and on one less common variety (021 WP). Two uncommon varieties (015 OR, 021 P) suffered moderate levels of damage with the remainder suffering only trivial levels. The mite’s impact in South Africa could be improved by complementing the established biotype with others from Central and South America that are better matched with the poorly attacked L. camara varieties.  相似文献   

7.
8.
Three species are described here that occur in montane and high-montane forests in Southeastern Brazil.Miconia shepherdii belongs to sectionGlossocentrum and occurs on the Serra da Mantiqueira, on the border between the states of São Paulo, Minas Gerais, and Rio de Janeiro.Miconia kollmannii belongs to sectionHypoxanthus (formerChaenanthera) and occurs in the state of Espírito Santo.Ossaea suprabasalis was also collected in the state of Espírito Santo.  相似文献   

9.
Passiflora boticarioana, a new species of subgen.Passiflora, supersect.Stipulata, sect.Dysosmia, from the state of Minas Gerais, Brazil, is described, illustrated, and compared with morphologically similar species.  相似文献   

10.
11.
Cryptostegia madagascariensis is a plant native from Madagascar, belonging to the Apocynaceae that is invading the native vegetation in Northeast Brazil and threatening the unique riverine formations dominated by the carnauba palm. Individuals of C. madagascariensis cultivated in the campus of the Universidade Federal de Viçosa, state of Minas Gerais, Brazil, showing leaf spot symptoms of unknown etiology were observed. Two fungal species were found associated to such leaf spots: Colletotrichum gloeosporioides and a new species of Pseudocercospora. The latter was named Pseudocercospora cryptostegiae-madagascariensis and described herein. The discovery of those two fungal pathogens on C. madagascariensis coincide with the recognition that the weedy vine that is involved in the infestations in the Northeast of Brazil is not Cryptostegia grandiflora as formerly reported. These mycological findings are of greater importance now since C. madagascariensis is likely to become a target for biological control together with its former status in Brazil of an ornamental plant of limited relevance.  相似文献   

12.
《Biological Control》2006,36(2):247-257
The seed damaging fly, Ophiomyia lantanae is a widespread agent that infests the fruits and seeds of Lantana camara. Its effectiveness in reducing seed dispersal or seedling recruitment has not been comprehensively tested. We determined the effects of O. lantanae damage on fruit removal rates of L. camara in a field study. We also investigated recruitment responses (seed germination in growth cabinets and seedling emergence in pot trials) of two common L. camara biotypes, pink and pink-edged red (PER) to O. lantanae damage. We found that fewer damaged fruits were removed than undamaged fruits, suggesting that frugivores select against damaged fruit. In all recruitment experiments, the responses to damage were biotype dependent. In germination experiments, these differential responses were primarily due to significantly reduced germination of damaged PER seeds. Seedling emergence from pots of the PER biotype was also lower in damaged seeds (27.5%) than undamaged seeds (56.1%). In contrast, emergence increased with seed damage in the pink biotype, from 28.2 to 41.1%. O. lantanae damage significantly reduced seed mass only in the smaller seeded PER biotype. In the larger seeded pink biotype, it may have promoted seedling emergence by interfering with dormancy mechanisms. We also examined in situ seed banks at L. camara populations prior to peak seed production. Mean viable seed densities ranged from 78.6 to 402.8 seeds m−2. Of these, non-dormant seeds comprised 24.6 to 98.2 seeds m−2, suggesting that recruitment is unlikely to be seed limited. We conclude that while O. lantanae influences recruitment and dispersal processes, the magnitude of the responses measured are unlikely to greatly influence plant densities in south-east Queensland infestations.  相似文献   

13.
Three new species of Eupatorieae (Asteraceae) were collected in the “campos rupestres” of the Cadeia do Espinha?o, Minas Gerais state, Brazil, in the Itacolomi State Park, located between the cities of Ouro Preto and Mariana, Minas Gerais, Brazil, during a floristic survey focusing on Compositae in this area. Eupatorium semiamplexifolium, Mikania badiniana, and Stevia alexii are described and illustrated.  相似文献   

14.
Anastrepha entodonta n. sp. and Anastrepha hadropickeli n. sp. are described and illustrated. The new species belong to the spatulata group. Both species occur sympatrically with Anastrepha pickeli Lima in the semiarid region of the state of Minas Gerais, Brazil. Anastrepha hadropickeli occurs also in the semiarid of the state of Rio Grande do Norte, Brazil, where it was misidentified as A. pickeli.  相似文献   

15.
Lopesia indaiensis (Diptera, Cecidomyiidae), a new species of gall midge found causing galls on Andira fraxinifolia (Fabaceae), an endemic plant species in Brazil, is described based on larva, pupa, male and female. L. indaiensis galls were collected in Dores do Indaiá, State of Minas Gerais, Southeastern Brazil. Larvae were removed from the galls and pupae and adults were obtained by rearing. The specimens were mounted on slides and the most important morphological characters were illustrated. The new species was compared to the other species of Lopesia.  相似文献   

16.
Epiphytes play an important role in the flora and ecology of the tropical regions. Most floristic studies within the state of Minas Gerais focus on terrestrial, woody plant diversity, but this is a different approach, looking at epiphytic angiosperms in three highland areas in Southeastern Minas Gerais, namely Mata do Baú (MB), Reserva Biológica da Represa do Grama (RBRG) and Parque Estadual de Ibitipoca (PEI). Regular collections were performed in these sites between 1999 and 2007, complemented by herbarium records for PEI, and 181 species of epiphytic angiosperms were recorded in 66 genera, within 12 families. Orchidaceae, with 89 species, was by far the largest, and the most species rich genera were Peperomia (Piperaceae) and Pleurothallis s.l. (Orchidaceae), with 12 species each. Similarity analysis has shown a closer relationship between MB and RBRG, both composed by seasonal semideciduous forest, however, Jaccard (0.163) index are low. A similarity analysis including other 21 areas of southeastern and southern Brazil revealed strong influence of sazonality, vegetation type and altitude in the composition of the epiphytic flora, and a relative independence regarding the geographic proximity of the areas sampled. From the conservation standpoint, 30 species recorded for this work appear in the red list for the state of Minas Gerais, under different conservation categories. The low similarity indices obtained between the studied areas underline the importance of the conservation of each one of the remaining forest fragments in Minas Gerais, as their relative geographical proximity does not necessarily mean that their epiphytic flora is similar.  相似文献   

17.
The sediments of 10 samples of geopropolis collected from 3 species of Meliponinae in the states of Espírito Santo, Minas Gerais and São Paulo, Brazil, and obtained after chemical treatment, were analysed. Pollen grains, hyphae and spores of fungi, organic material and burned plant fragments were observed in the majority of samples. Sandy or earth materials was present in all geopropolis sediments. Pollen analysis identified the dominant, accessory and isolated plant taxa occurring in the areas of geopropolis sample recovery. The most important pollen types found were Eucalyptus (Myrtaceae) in samples from the state of São Paulo only, Schinus (Anacardiaceae) mainly in samples from the state of Minas Gerais and Myrcia (Myrtaceae) in every state. Two samples were devoid of pollen grains. Only one sample contained plant trichomes and was considered a propolis sample of Apis bees. Compared to propolis samples examined previously, the geopropolis pollen spectra reflect the characteristic regional vegetation and also a higher variability of plant species visited by the Meliponinae. It is established that geopropolis samples can be distinguished from propolis samples by light microscope analysis of sediments. Mineral and soil constituents, as well as the lack of trichomes, are characteristic only of geopropolis.  相似文献   

18.
Campomanesia simulans, a new species from the states of São Paulo and Minas Gerais, Brazil, is described and illustrated.  相似文献   

19.
A species ofPseudolaelia (Orchidaceae) from Minas Gerais, Brazil, is described as new to science.  相似文献   

20.
A new species of troglobitic harvestman, Iandumoema smeagol sp. n., is described from Toca do Geraldo, Monjolos municipality, Minas Gerais state, Brazil. Iandumoema smeagol sp. n. is distinguished from the other two species of the genus by four exclusive characteristics – dorsal scutum areas with conspicuous tubercles, enlarged retrolateral spiniform tubercle on the distal third of femur IV, eyes absent and the penial ventral process slender and of approximately the same length of the stylus. The species is the most highly modified in the genus and its distribution is restricted only to caves in that particular area of Minas Gerais state. The type locality is not inside a legally protected area, and there are anthropogenic impacts in its surroundings. Therefore, Iandumoema smeagol sp. n. is vulnerable and it must be considered in future conservation projects.  相似文献   

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