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Colombo, Brazil

Ferreira B.G.A.,Federal University of Parana | Zuffellato-Ribas K.C.,Federal University of Parana | Wendling I.,Estrada da Ribeira | Koehler H.S.,Federal University of Parana | Reissmann C.B.,Federal University of Parana
Ciencia Florestal

Psychotria nuda (Cham. & Schltdl.) Wawra (Rubiaceae) is a native species from the Dense Ombrophylous Forest (dense tropical rain forest), typical in the low altitude areas of the forest, with occurrence in the states of Minas Gerais, Rio de Janeiro, São Paulo, Paraná and Santa Catarina. Due to the presence of yellow flowers with red receptacle and anise colored fruits, the plant has an ornamental potential, such as a pharmaceutical potential, thanks to the variety of alkaloids that have already been isolated demonstrating structural diversity of its active components. This work aimed to verify the effect on stem cuttings rooting of different collection environments and of different phenophases of Psychotria nuda stock plants at the time of collection, and to verify what is the correlation between variables defined as percentage of rooted cuttings, number of roots per cutting and average length of the three longest roots per each cutting (cm) with permanence of two half leaves and formation of callus. Phenophases are intended as different times of the year in which stock plants presented distinct phenological characteristics. In the two phenophases studied (phenophases 1 and 2) canopy sprouts were collected in Antonina, Paraná state, from two different environments (plain and hillside) of the Dense Ombrophylous Forest (dense tropical rain forest). Cuttings were prepared with 10 to 13 cm length and two halved leaves. After 60 days in a greenhouse, the percentage of cuttings with roots, with callus, alive, dead, the number of roots per cutting and the length of the three longer roots per each rooted cutting were evaluated. The collection environments and the phenophases at the time of collection infuenced the percentage of rooting, such that the phenophase 1 and the hillside environment were the conditions that resulted in the best rooting percentage (90%). The permanence of leaves during rooting period helped, in most cases, the formation of adventitious roots. Anticipated formation of callus supported rooting in phenophase 2, while in phenophase 1 the formation of adventitious roots was independent from callus formation. Source

Beckert S.M.,Federal University of Parana | Rosot M.A.D.,Estrada da Ribeira | Rosot N.C.,Federal University of Parana
Scientia Forestalis/Forest Sciences

In order to understand the dynamics and growth processes of Araucaria angustifolia (Bert.) O. Ktze., this study evaluated the behavior of the following variables: number of trees, diameter, basal area.ha-1 and volume. ha-1 of this species over eight consecutive years by the measurement of permanent plots established in a remnant of Araucaria Forest, located in Caçador - SC, which presents large individuals of A. angustifolia and an understory occupied by bamboos. Therefore, two hypotheses were evaluated: i) growth and yield of the variables tend to remain stable or decrease over time and ii) recruitment of new individuals is low or nonexistent. The results show a reduction in the number of trees, in average basal area and stand volume per hectare due to mortality and absence of natural regeneration. There was an average increase about 3 cm in diameter, ranging from 75.95 cm to 78.57 cm, and the mean periodical annual increment (PAI) of 0.33 cm.year-1. The average basal area decreased by 4.80 m2.ha-1, ranging from 32.75 m2.ha-1 to 27.95 m2.ha-1. Average volume per hectare decreased by 78.38 m3.ha-1 with a negative PAI of 9.8 m3.ha-1.year-1. Statistically significant differences were noted mainly in response to weather events that have raised the rate of mortality in the third and sixth years of measurement. Source

Fuzitani E.J.,APTA | dos Santos A.F.,Estrada da Ribeira | Moraes W.S.,APTA | Damatto Junior Jr. E.R.,APTA | Nomura E.S.,APTA
Revista Brasileira de Fruticultura

The exploitation of heart of palm in Brazil is no more an extractive activity; it is becoming a commercial production due to the planting of palm trees such as peach palm (Bactris gasipaes Kunth var. gasipaes Henderson). The stem base rot (SBR) caused by Phytophthora palmivora has emerged as an important disease, which may limit the peach palm production in many regions. This disease occurs in young and adult plants. This study aimed to evaluate the efficiency of preventive and curative application of phosphites on SBR incidence and its severity in peach palm seedlings under greenhouse conditions. Three experiments were carried out, as follows: I - preventive and curative effect of phosphites, following factorial scheme 6 x 2 (phosphites x application time); II - effect of preventive application of potassium phosphite, following factorial scheme 6 x 4 (number of applications x evaluation periods), and III - Effect of preventive and curative methods and application periods of potassium phosphite, following a factorial scheme 2 x 2 (application forms x dosage). Disease severity was assessed at 28 days in experiment I and III in the experiment, while in experiment II was evaluated at 7, 14, 21 and 28 days after inoculation, based on descriptive scale with a scale from 0 to 4. Treatments were carried out in a completely randomized design with 10 repetitions of one seedling for each repetition. Data were submitted to variance analysis and when treatment means were significant by F test (p < 0.05) they were compared by Tukey test at 5% of probability. From the results obtained, it was concluded that potassium phosphite have better control between phosphites tested, and when applied preventively at 2.5 mL.L-1 with 3 applications and dosage of 5.0 mL. L-1 with 2 or 3 applications significantly reduced the incidence and the severity of SBR in peach palm seedlings. But, when applied as curative had no effect, regardless of the dose or the number of applications. Since the best time for severity assessment of SBR was 21 days after inoculation of Phytopthora palmivora. Source

Silva E.A.,Federal University of Lavras | Gomes J.B.V.,Estrada da Ribeira | Filho J.C.A.,Unidade de Execucao de Pesquisa UEP | Silva C.A.,Federal University of Lavras | And 2 more authors.
Revista Brasileira de Ciencia do Solo

The soils associated to depressed summits on the Coastal Plains are still little studied in Brazil and are differentiated in several aspects. Generally, the closer a soil is to these depressions, the sandier is the texture and the more accentuated the hydromorphism, where the occurrence of Spodosols is common. The objective of this work was to perform different extractions of Fe, Al, Si and organic C to understand the podzolization process in soils of the summit depressions of the Coastal Plains of Northeastern Brazil. For this purpose, soil profiles were described and samples collected in four areas: Coruripe, AL; Neópolis, SE; Acajutiba, BA; and Nova Viçosa, BA. In these samples, the Fe, Al and Si contents were determined by the sodium dithionitecitrate- bicarbonate, ammonium oxalate and sodium pyrophosphate extractors and soil organic matter was chemically fractionated. The increase in organic C, and Fe and Al contents by different extractors from the iluvial (accumulation) horizons of each soil, relatively to the eluvial (loss) horizons, reflects the field morphology and reinforces the importance of the podzolization process in the studied soils. Complexes of Al-humus entirely dominate the matrix of the iluvial horizons associated to hydromorphism, while there is a variable influence of different Fe forms on those with no hydromorphism. The Ferrihumiluvic Spodosol profile is the only one of the four studied profiles with spodic horizons with "s" subscript, i.e., where the contents of extracted Fe affected the morphology differentially. Source

Ferreira B.G.A.,Federal University of Parana | Zuffellato-Ribas K.C.,Federal University of Parana | Wendling I.,Estrada da Ribeira | Koehler H.S.,Federal University of Parana | Nogueira A.C.,Federal University of Parana
Ciencia Florestal

Sapium glandulatum (Vell.) Pax (Euphorbiaceae) is a native and rustic tree found in different Brazilian plant formations, and is much indicated for recovery of degraded ecosystems. However, the sexual propagation is very difficult because almost every flower is male, the seed production is poor and the percentage of seed germination is low. The mini-cuttings technique is an alternative to other methods of propagation that allow the rooting with young material. Thus, the present work aimed to test the sprouts production and rooting by mini-cuttings of Sapium glandulatum (Vell.) Pax originating from young seedlings, collected in four seasons (autumn, winter, spring 2006 and summer 2007), in Colombo - PR Brazil. The mini-cuttings were trimmed to 3 cm in length, with two half leafs in apical region. Indolebutyric acid (IBA) and naphtalene acetic acid (NAA) were applied in the base of the mini-cuttings at 0, 2000, 4000, 6000 and 8000 mgL -1 for 10 seconds. The percentage of rooted mini-cuttings, amount and root length, percentage of mini-cuttings with callus, survival and mortality rate were evaluated in a experimental random delineation, with factorial range of the treatments: 2x5x4 (kinds of plant growth regulator x concentration of plant growth regulator x seasons). The mini-cuttings production/mini-tumps range between 1.4 until 2.2 in 205 cm 3 recipient. The best season for rooting was winter, with 80.56% of rooting when the vegetal regulator was not used. It is concluded from this study that the vegetative propagation of Sapium glandulatum (Vell.) Pax by mini-cuttings collected from young seedlings can be used for rooting. Source

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