Desiccation tolerance of four seedlots from Euterpe edulis Mart.

In order to identify the desiccation tolerance of E. edulis seeds, four fruitlots were collected from the Campinas Agronomic Institute Palmae collection, located at Ubatuba, state of Sao Paulo, Brazil, and taken in moisture-proof containers to the College of Agriculture in Botucatu, state of Sao Paulo. There, the fruits were shelled and the seeds were dried, either under silica gel conditions or in a drying chamber. The effects of dehydration were evaluated by measurements of the germination, embryo protrusion, germinative button, plumule, speed of emergence, seedling length, seed dry matter and water content. Differences among seedlots and between harvest season for most of the traits were observed. Euterpe edulis seedlots seem to tolerate water content reductions until 39% without significant reduction in germination and vigor. Below this value, most of the evaluated traits were negatively affected. Total loss of germination was observed whenever seed water content was reduced to values below 21%.

Brazil's emergence at the regional export leader in services: a case specialization in business services

Includes Bibliography

Emergence de l'euro: implications pour l'Amérique latine et les Caraïbes

Inclut la bibliographie

Morfologia de sementes e de estádios iniciais de plântulas de espécies de Bromeliaceae da Amazônia

Seeds of Aechmea bromeliifolia, A. castelnavii (Bromelioideae); Dyckia duckei, D. racemosa (Pitcairnioideae) and Tillandsia adpressiflora (Tillandsioideae) were collected in the Amazon regions (Mato Grosso) and studied to describe morphological characterization and post-seminal development, which can be taxonomically useful, and to assess percent germination. All the species have epigeous germination and produce cryptocotyledonary plantlets. Seeds have no dormancy and percent germination is high (over 86%), which facilitates the production of seedlings and conservation studies. Exclusive characteristics of the genera include: the seed coat of Aechmea (Bromelioideae) has mucilage that prevents desiccation; whereas that of Dyckia (Pitcairnioideae) has membranaceous wings and that of Tillandsia (Tillandsioideae) has feathery appendages, both of which make dispersal easier and establish the epiphytic habit. Initial post-seminal development of Aechmea (Bromelioideae) and Dyckia (Pitcairnioideae) is marked by the emergence of primary roots, interpreted as a basal character, whereas that of Tillandsia adpressiflora (Tillandsioideae) is marked by the emergence of the cotyledon, interpreted as a derived character. Dyckia and Tillandsia have a small tank only in the seedling phase while the contrary occurs in Aechmea.

Avaliação de substratos na emergência de plântulas de araticum-de-terra-fria (Annona emarginata (Schltdl.) H. Rainer)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Seedling growth of Schizolobium parahyba on different substrates and irrigation levels

The present study aimed to assess the behavior of seedlings of Schizolobium parahyba (Vell.) Blake growing on different substrates and irrigation levels, and to study the use of urban waste compost in substrates. The experiment was carried out in the College of Agricultural Sciences, Universidade Estadual Paulista (UNESP), Department of Agricultural Engineering, Jaboticabal Campus, state of São Paulo, Brazil. The experimental design used was completely randomized, consisting of 30 treatments in a factorial design with 15 substrates and two irrigation levels in four replicates. The substrates were composed of different materials: urban waste, Plantmax®, dry cattle manure, vermiculite and soil. For the study of seedling growth, the following characteristics were evaluated: height (H), root-collar diameter (D), number of leaves, shoot dry weight, root dry weight, total dry weight, H/D ratio, Dickson's quality index, and the ratio between height and shoot dry weight (H/SDW). Assessments of the first three characteristics were carried out 20, 35, 50 and 65 days after sowing. Results showed that urban waste compost increased the growth of Schizolobium parahyba. There were significant differences for the irrigation levels tested; with better results for 150% ET compared to 100% ET irrigation level.

Supressão de água em diferentes fases fenológicas do feijoeiro (Phaseolus vulgaris L.)

Bean (Phaseolus vulgaris L.) is widespread in the Brazilian social and economic scene. The hypothesis is that if the water supply is suppressed in just one of the five development stages of irrigated beans, it can result in yield reduction lower than 20%, allowing water economy. The objective of this study was to compare the performance of bean Carioca group IAC Alvorada yield components, with irrigation suppression in each of the five phenological phases (emergence, vegetative, flowering, grain filling and maturation) and no irrigation and irrigated in all stages. The study was conducted at Agronomical Sciences College, UNESP, Botucatu, SP, Brazil. The statistical design was the randomized block with seven treatments and four replications. Data were subjected to analysis of variance and t test at 5% probability. A rainfall event (58 mm) after planting allowed the successful emergence of seedling beans in plots where water would not be applied. The yield components were higher affect when there was irrigation's suppression at Vegetative phase and at Flowering phase. The treatments where occurred irrigation suppression at Maturation and at Emergence showed yield reduction of less than 20%, proving the hypothesis.

Seed and seedling surface-sterilization for in vitro culture of tillandsia gardneri (Bromeliaceae)

Tillandsia gardneri is a bromeliad with ornamental value and a wide geographical distribution over Brazil. However, due to habitat loss and illegal overcollection in the wild it is included as a vulnerable species in the official list of endangered plants of the State of Rio Grande do Sul, Brazil. The development of a protocol for T. gardneri seed propagation in vitro may be useful for reintroducing plants in their natural habitats, and for germplasm conservation. A difficult problem encountered during the establishment of an in vitro culture is explants disinfection, especially when working with endangered species, from which explant availability is restricted. Thus, the establishment of a sterilization protocol is crucial for the initiation and success of a micropropagation system for T. gardneri. The objective of this study was to evaluate the effect of sodium hypochlorite concentration and exposure time in seed and seedling surface disinfection, tissue sensitivity and development. Sodium hypochlorite solutions (10 or 20%/5, 10 or 15 min; 25%/5 or 10 min; and 50%/5 min) were effective in eliminating seed superficial contaminants. There was no significant difference among the effective sterilization treatments in relation to seed germination (%), and seedling length and number of leaves, after 120 days in vitro. Also, no damage to seed and seedling tissues were observed. Surface sterilization of seedlings, for initiation of an in vitro culture, required higher concentrations of sodium hypochlorite (25%/15 min; 20 or 50%/5, 10 or 15 min; and 40%/5 and 10 min) for controlling fungal and yeast contamination, compared to seed sterilization. No significant differences among these treatments were found in relation to seedling length and number of leaves, after 60 days in vitro.

Caracterização morfológica do diásporo e da plântula de Archontophoenix cunninghamii (Arecaceae)

The palm Archontophoenix cunninghamii H.Wendl. & Drude, even widely used in landscaping, has been poorly studied. In general, there are few articles on morphology of seeds and seedlings of Arecaceae species. With the aim of filling this gap, the objective of the present work describes the diaspore (seed with adhering endocarp) and the seedling morphology. A. cunninghamii seeds present rounded shape and a ruminated endosperm of hard consistency. The embryo is lateral, peripheral and relatively undifferentiated, approximately 4 mm long, conical, with one of the extremities convex, and in its inside there is a small protuberance while the other extremity is rounded and narrower. The seedling is adjacent ligulated and hypogeal, with the development starting from a mass of undifferentiated cells in the micropillar depression, the differentiation of shoot and root primordium, being the first enveloped by a sheath closed. The root system is fasciculate, with different adventitious roots and several lateral roots with few absorbent hairs. The stem comprises three sheaths surrounding the first young leaf, which are opened in succession, permitting the emergence of the primary bifid leaf, with typical parallel nerves.

The emergence of Latin multinationals

Includes bibliography

Seedling morphology and development in the epiphytic cactus Epiphyllum phyllanthus (L.) Haw. (Cactaceae: Hylocereeae)

Seedling morphology is relevant in classification, taxonomy, and vegetation studies to understand plant life cycles, germination succession and requirements, and developmental progression. However, most morphological studies of seedlings lack analysis of organ anatomy, impeding the comprehension of series of development and establishment in a particular environment. Here, we have taken a traditional anatomical approach to examine the stages of seedling development in Epiphyllum phyllanthus, a holo-epiphytic cactus of tribe Hylocereeae. The goals were 1) to offer a comprehensive description of growth series in E. phyllanthus seedlings based on morphological and anatomical analysis and 2) to examine the initial growth phases in the life cycle of this species to identify organ development and understand their adaptive significance in relation to seedling establishment. Our results include descriptions of seed morphology, embryonic features, and seedling vascularization pattern in the root, hypocotyl, cotyledons, and epicotyl. The morphological and developmental patterns in E. phyllanthus seedlings have potential phylogenetic and ontogenetic implications in the Cactaceae. Characters such as the presence of mucilage on the seed coat, the lack of seed operculum, and large cotyledons in E. phyllanthus are comparable to basal cacti, but the root anatomy is more similar to columnar relatives. At the familial level, there is an apparent trend in decreasing number of phloem and xylem poles in the stele of primary root, correlated with degree of specialization and advanced phylogenetic position: tetrarch to septarch-octarch in basal lineages, tetrarch Cereus-type in columnar species, to the diarch vascular system in Rhipsalideae and some species with cylindric/globose stem. © Torrey Botanical Club.

Cryopreservation, early seedling development, and genetic stability of Oncidium flexuosum Sims

An efficient cryopreservation protocol was developed for mature seeds of Oncidium flexuosum Sims. Seed morphology, protocorm formation, and early seedling development were also assessed. The effects of phloroglucinol and Supercool X-1000® as cryoprotectant additives in the vitrification solution were investigated. Dehydration using the plant vitrification solution 2 (PVS2) for 60 and 120 min prior to immersion in liquid nitrogen promoted the highest frequency of in vitro seed germination 6 weeks following culture on half-strength Murashige and Skoog (1/2 MS) medium. Mature seeds submitted to vitrification for 120 min in PVS2 and 1 % phloroglucinol at 0 °C enhanced germination by 68 %, whereas in PVS2 and 1 % Supercool X-1000® germination was just moderately enhanced (26 %). In vitro-germinating seedlings developed healthy shoots and roots without the use of plant growth regulators. After 6 months of growth, there were no differences between in vitro- and ex vitro-grown seedlings for various phenotypic characteristics, including shoot length, number of leaves, number and length of roots, and fresh and dry weight. Seedlings were transferred to greenhouse conditions and successfully acclimatized, further developing into normal plants with over 90 % survival. Comparative analysis of seedlings from control and vitrified seeds using flow cytometry indicated that no change in ploidy levels occurred as a result of cryopreservation, therefore maintaining seedlings genetic stability. In this study, vitrification with PVS2 for 120 min with the addition of 1 % phloroglucinol offers a simple, safe, and feasible protocol for cryopreservation of O. flexuosum mature seeds. © 2013 Springer Science+Business Media Dordrecht.

No changes in seedling recruitment when terrestrial mammals are excluded in a partially defaunated Atlantic rainforest

One of the most intriguing questions in ecology is how to identify which and how many species will be able to inhabit human-modified landscapes. Large-bodied mammals structure plant communities by trampling, herbivory, seed dispersal and predation, and their local extinction may have pervasive consequences in plant communities due to the breakdown of key interactions. Although much attention has been given to understanding the effects of defaunation on plant communities, information on the potential impacts on plant functional groups (seed dispersal, seed size and seedling leaves defense) inhabiting continuous forests after defaunation is scarce. We conducted mammal surveys (line transects and camera trapping) to determine the defaunation status of a continuous Atlantic forest in Brazil. Then, we evaluated the effects of defaunation on seedling diversity, richness and abundance of functional groups using 15 plot-pairs (each pair with one open and one exclusion plot) monitored over 36. months. We found that the studied area is partially defaunated because it exhibits high abundance of primates, while terrestrial mammals, such as large rodents and ungulates, are rare. We found no significant changes in either seedling richness and diversity or in the seedling composition of plant functional groups in response to mammal exclosure. Seedling mortality and recruitment were similar between plot types. Our findings suggest that at semi-defaunated areas, where arboreal species are still present, terrestrial mammals have low impacts on the plant community reassembly. © 2013 Elsevier Ltd.

Herbicide selectivity in herbaceous ornamental gardens of tagetes erecta L.

One of the major problems in landscaping in tropics is weed management. The herbaceous ornamental plant, Tagetes erecta L. (Asteraceae), is very popular for its beautiful flowers which can be used in landscape and also as cut flowers. The increase use of this plant and lack of selective herbicides led to the objective of this study to evaluate the herbicide metribuzin selectivity for this ornamental plant. The experimental design was completely randomized using four treatments (herbicide metribuzin doses: 0, 0.5, 1.0 and 1.5 L ha-1, equivalent to 0, 240, 480 and 720 g ha-1) and five replicates. The herbicide was applied over the seedling of T. erecta as pre-emergence of the weed seeds. Evaluations were performed at 7, 14, 21 and 28 days after application (DAA) by visual analysis of the toxicity symptoms over the ornamental, using the European Weed Research Council (EWRC) scale (1 to 9), where 1 is the total absence of symptoms and 9 to death plants. Polynomial regression statistical analysis was used. It was verified that, from the dose of 1.0 L ha-1, T. erecta plants died by 14 DAA, which the most of them had presented a very strong toxicity symptom; for the 0.5 L ha-1 treatment the plants had survived until 28 DAA. However, most of them already exhibited the high toxicity level, dying at 35 DAA. Thus, metribuzin was not suitable for T. erecta even at the lowest rate tested in this study.

Dessecação com Glyphosate em pré-colheita e qualidade fisiológica de sementes de soja

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)