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Studies on pollination and seed dispersal are essential for the conservation of plant diversity. In this study, we aimed to evaluate the pollination and dispersal syndromes of five fragments of the Cerrado Rupestre immersed in an agricultural landscape to answer the following questions: (i) What is the frequency of pollination and dispersal syndromes among species and individuals?; (ii) Which are the predominant pollination and seed dispersal syndromes in this environment?. A total of 66 species, belonging to 44 genera and 29 botanical families, were evaluated. Melittophily was the most common type of pollination syndrome, observed in 54.55% of the species, followed by phalenophily (9.09%), cantharophily, ornithophily, quiropterophilly and sphingophily (all 3.03%), and psychophilly (1.51%). Generalist pollination represented 22.73% of the records. Of the 1246 individuals identified, 59.23% were melitophilous, 25.20% generalists, 5.86% phalenophilous, 3.37% quiropterophilous, 2.49% cantharophilous, 2.25% ornithophilous, 1.44% sphingophilous and 0.16% psychophilous. Regarding dispersion syndromes, zoochory was the most common type of dispersion, observed in 68.18% of the species, followed by anemochory (28.79%) and autochory (3.03%). On the other hand, the frequency among individuals differed from the values found for frequency among species. Of the 1246 individuals identified, 55.38% were anemochoric, 43.10% zoochoric, and 1.52% autochoric. Our results demonstrate the predominance of biotic syndromes in the community, especially melittophily and zoochory, contributing to a better understanding of the functionality and availability of resources in the community, as well as indispensable information for the conservation, management, and restoration of natural environments.

O objetivo deste estudo foi analisar a florística e a estrutura da regeneração natural de uma área de Caatinga, na Floresta Nacional Contendas do Sincorá, Bahia. A amostragem consistiu em 48 parcelas de 5 x 5 m. Os parâmetros fitossociológicos utilizados foram densidade, frequência, classe de tamanho e a regeneração natural relativa. A influência de variáveis ambientais na densidade das espécies foi investigada por meio da Análise de Correspondência Canônica. Foram amostrados 771 indivíduos, distribuídos em 22 famílias, 37 gêneros e 44 espécies e nove morfo-espécies. Croton floribundus e Combretum monetaria obtiveram os maiores índices dos descritores vegetacionais. A similaridade florística teve a formação de um grupo com áreas da Depressão Sertaneja Setentrional. Mimosa ophthalmocentra teve uma relação fortemente positiva com a altitude. Combretum monetaria, Libidibia ferrea e Piptadenia stipulacea foram influenciadas pela maior precipitação. A maior precipitação na Flona foi determinante para dissimilaridade com as demais áreas.

ABSTRACT Our research focused on the reproductive phenology of Mauritiella armata, a key veredas species in southeastern Brazil, and aspects of its floral and fruit morphology and sexual system. We observed the reproductive phenological patterns of M. armata for 36 months, and examined the relationships between phenophases and environmental variables to describe its phenological patterns in relation to environmental filters, as well as its floral and fruit morphologies, sexual system (to evaluate dioecy), and the biometry of its reproductive parts. Flowering was observed in the dry season and at the beginning of the rainy season, with fruiting occurring during the rainy season. The reproductive phenophases responded to environmental seasonality, principally temperature in the period immediately preceding the expression of the phenophase, as well as to environmental variations that had occurred up to six months earlier. The dioecious sexual system of M. armata was confirmed, with flowering synchronization between the sexes. The population studied did not exhibit apomixis, having xenogamy as its reproductive system. The staminate inflorescences were larger than the pistillate inflorescences and had greater numbers of flowers, although the pistillate flowers were larger. Wind pollen dispersal was not observed, thereby indicating that this species requires biotic pollination for fruit production.

The present study evaluated floristic composition, similarity and the phytogeographic structuring framework of Caatinga in the Contendas do Sincorá National Forest. The climate of the region is BSwh', with annual precipitation of 500 to 700 mm and altitude between 300 and 400 m. The soil is eutrophic red-yellow ultisol. Floristic similarity was established by the unweighted pair group method with arithmetic mean. Fifty-one (51) taxa were found distributed in 20 families. The families with the largest number of genera and species were Fabaceae and Euphorbiaceae. The classification for this physiognomy was Woody Savanna-Steppe. Floristic similarity revealed a tendency of grouping between fragments of the same state and ecoregion. Despite the history of exploitation, the floristic composition was as expected for Caatinga areas. The similarity analysis revealed that the area in question does not have a similar floristic identity to the other Caatinga areas analyzed.

The flora of the Rupestrian Savannah (Cerrado Rupestre) is composed of widely distributed species and endemic species from high altitude rocky outcrops. The aim of this study was to characterise the floristic composition, structure and diversity of fragments of Rupestrian Savannah in south-eastern Brazil and to examine the similarity with other rupestrian cerrado vegetations and with cerrado sensu stricto on profound soils. For this, phytosociological parameters, evenness and diversity were calculated and compared with other studies. The survey exhibited 72 species, 45 genera, 30 families and high floristic similarity with cerrado on profound soils. There were no indicator species of the Rupestrian Savannah, but there were typical species of rocky environments. The basal area was significantly larger in the profound soil cerrado in relationship to the Rupestrian Savannah and evenness was lower in the Rupestrian Savannah of this study compared to others. These variables reflect the lower exploration capacity of the root of rocky environments. The highest similarity between the Rupestrian Savannah and cerrado on profound soils refers to the canga ferruginous nature, which represents the limit of the tableland of cerrado on the edge of the plateaus, allowing greater sharing of flora.

Atividades antrópicas promovem alterações em diversas características abióticas do meio, ocasionando mudanças em um dos mais consistentes padrões da ecologia, a relação espécie-área. Objetivamos avaliar as relações entre riqueza/abundância de plantas e área dos montes em campos de murundus (campos sazonalmente alagados com montes espaçados) circundados por matriz antrópica. Ademais, avaliamos como atividades antrópicas afetam essas relações e as síndromes de dispersão das comunidades. Amostramos dois campos de murundus, ambos circundados por monoculturas, um impactado (CMI) e outro protegido (CMII). Encontramos redução no número de espécies com o aumento da área do murundu no CMI e relação oposta no CMII. A abundância de indivíduos foi positivamente relacionada à área do murundu nos dois campos. Já em relação à síndrome de dispersão, a maior diversidade de síndromes foi encontrada no CMI. A área é um fator determinante dos padrões de riqueza e abundância de plantas nos murundus, mesmo em ecossistemas circundados por matriz antrópica. Como os campos avaliados estão expostos às mesmas condições climáticas e apresentam estrutura semelhante, a relação espécie-área negativa encontrada no CMI indica que a pressão antrópica nesse campo já foi efetiva em eliminar espécies e romper com um padrão esperado para as comunidades naturais.

The long-lived flowers of orchids increase the chances of pollination and thus the reproductive success of the species. However, a question arises: does the efficiency of pollination, expressed by fruit set, vary with the flower age? The objective of this study was to verify whether the flower age of Corymborkis flava(Sw.) Kuntze affects pollination efficiency. The following hypotheses were tested: 1) the fruit set of older flowers is lower than that of younger ones; 2) morphological observations (perianth and stigmatic area), stigma receptivity test by using a solution of hydrogen peroxide and hand-pollination tests are equally effective in defining the period of stigmatic receptivity. Flowers were found to be receptive from the first to the fourth day of anthesis. Fruit set of older flowers (third and fourth day) was lower than that of younger flowers. Morphological observations, the stigma receptivity test and hand-pollinations were equally effective in defining the period of stigmatic receptivity. However, to evaluate the maximum degree of stigma receptivity of orchid species with long-lived flowers, we recommend hand-pollinations, beyond the period of receptivity.

O objetivo desse trabalho foi avaliar a regeneração natural e a abundância de espécies exóticas no sub-bosque de um plantio experimental de Araucaria angustifolia, em Viçosa, MG. A amostra correspondeu a 40 parcelas de 2 m x 2 m, onde mediu-se o diâmetro ao nível do solo (DNS) de todos os indivíduos arbustivo-arbóreos com diâmetro ≤ a 5,0 cm e altura ≥ a 0,5 m. Foram calculados os parâmetros fitossociológicos e os índices de diversidade e equabilidade. As espécies foram classificadas quanto à forma de vida, classe sucessional e síndrome de dispersão. Foram amostrados 980 indivíduos, sendo observada maior proporção de espécies arbustivas, típicas de sub-bosque e zoocóricas. A espécie exótica Archontophoenix cunninghamiana, conhecida como palmeira australiana, obteve o terceiro maior valor de importância, a maior dominância e 19,25% da área basal total, valor consideravelmente maior que o das demais espécies. A. cunninghamiana foi caracterizada como uma espécie exótica invasora que domina o estrato de regeneração natural. A inibição da sucessão natural pela presença de espécies exóticas, como A. cunninghamiana, precisa ser monitorada, visando eliminar as espécies-problema, para garantir a continuidade do processo de sucessão.

The objectives of this study were to identify anthophilous butterflies on psychophilous flowers of four Asteraceae species in an Atlantic Forest fragment in Viçosa, Minas Gerais State, Southeastern Brazil, and to determine whether there are species in common with other lepidopteran inventories of the Southeastern and Midwestern regions of Brazil. It is the first inventory of anthophilous butterflies of a semideciduous forest fragment in Zona da Mata, State of Minas Gerais. A total of 108 species were recorded, representing the fourth largest lepidopteran survey in this State. The results demonstrated that Asteraceae species may be important tools for monitoring anthophilous butterflies. The similarity with other inventories ranged from 1 to 92.55%. Fifteen species were reported for the first time in the State of Minas Gerais, and among them, Melanis alena and Thisbe irenea were observed in this study only.

Cantharophily is reported for the first time in a Brazilian asclepiad, involving the mylerid Astylus variegatus and the nectariferous flowers of Oxypetalum banksii, a plant mainly pollinated by wasps. The use of nectar as food by A. variegatus, considered pollinivorous and granivorous, is also novel. The mutual interaction described here is an example of a plant-pollinator interaction with generalist insects visiting a plant with a specialized pollination system. It’s also temporary and occasional and, therefore, is often overlooked in studies of plant-pollinator interactions. In this study, we found that the casual meeting between O. banksii and A. variegatus was a key event for the reproduction of both.

O objetivo deste trabalho foi avaliar diferentes meios de cultura, utilizados sobre o ponto da enxertia, na microenxertia ex vitro para a eliminação do Cowpea aphid-borne mosaic virus (CABMV), em plantas de maracujá-azedo (Passiflora edulis Sims f. flavicarpa Deg.). Ápices caulinares, provenientes de plantas infectadas, foram microenxertados em plântulas obtidas pela germinação de sementes em substrato comercial esterilizado. Foram conduzidos experimentos com a microenxertia realizada no hipocótilo e no epicótilo, e foram utilizados cinco meios de cultura, que diferiam na concentração de fitorreguladores, aplicados no local da enxertia. O índice médio de microenxertos com folha expandida foi de 27,22 e 32,22%, quando a microenxertia foi realizada no hipocótilo e no epicótilo, respectivamente. Na microenxertia realizada no hipocótilo, não houve efeito da aplicação de meios de cultura. Na microenxertia realizada no epicótilo, o meio MS acrescido de 0,1 mg L-1 de AIB e 1 mg L-1 de BAP proporcionou 53,3% de microenxertos com folha expandida, número superior aos demais tratamentos e maior desenvolvimento das brotações. A indexação realizada pelo teste ELISA indireto, 80 a 100 dias após a microenxertia, mostrou que 93% das plantas testadas não apresentavam vírus detectável.The objective of this work was to evaluate the effect of different culture media, used over grafting spot, in ex vitro micrografting, in order to eliminate the Cowpea aphid-borne mosaic virus (CABMV) in sour passion fruit plants (Passiflora edulis Sims f. flavicarpa Deg.). Cauline apexes, originated from infected plants, were micrografted in seedlings obtained by the germination of seeds in commercial sterilized substrate. Experiments were conducted with the micrografting performed on the hypocotyl and epicotyl using five culture media, which differed on their concentration of phytoregulators applied on the grafting spot. The average rate of micrografting showing expanded leaf was 27.22 and 32.22%, when micrografting was performed on hypocotyl and epicotyl, respectively. In the micrografting performed on the hypocotyl, there was no effect of the culture media applied. In the micrografting performed on epicotyl, the MS medium supplemented with 0.1 mg L-1 3-indolbutiric acid (IBA) and 1 mg L-1 6-benzylaminopurine (BAP) resulted in 53.3% of micrografting showing expanded leaf, a number superior to the other treatments, and in a larger development of shoots. The indexing performed by the indirect ELISA test, within 80 to 100 days after micrografting, showed that 93% of the plants tested presented no detectable virus.