Colombo, Brazil
Colombo, Brazil

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Da Silva T.W.R.,Federal University of Paraná | Dos Santos A.F.,Estrada da Ribeira | Auer C.G.,Estrada da Ribeira | Tessmann D.J.,State University of Maringá
Ciencia Florestal | Year: 2017

The root rots (RR), caused by the Fusarium spp., causes loss of seedling in the nursery that show, initially, discoloration of the needles to a yellowish-green tone followed by apical curvature, wilt and the consequent death of the seedling. The objectives of this work were to: a) define the most appropriate and efficient method to detect Fusarium spp. in Pinus taeda seeds; b) verify if there is transmission of Fusarium spp. from seeds to Pinus taeda seedlings; c) develop a descriptive scale to evaluate the severity of the RR in Pinus taeda seedlings; d) evaluate the pathogenicity, aggressiveness and area under the disease progress curve (AUDPC) of isolated Fusarium subglutinans. For detection three treatments were applied to six lots of Pinus taeda seeds, bein four repetitions of 25 seeds: blotter test, paper card and selective medium. The transmission was evaluated in seeds from six lots of Pinus taeda during 60 days counting the percentage of emerged plantlet (EP), non-germinated seeds (NGS) and from NGS seeds with Fusarium spp. A descriptive scale of grades was developed to evaluate the severity of RR in Pinus taeda seedlings. The severity and the incidence of the illness were evaluated at 7, 14, 21 and 28 days after the inoculation from Pinus taeda seedlings of six months of age. The pathogenicity, severity and incidence of twelve isolated Fusarium subglutinans obtained in the detection test. To test for pathogenicity and aggressiveness 13 treatments with 15 replications were applied. The most sensitive detection method to detect Fusarium spp. on Pinus taeda seeds was the selective medium; transmission was not observed of Fusarium spp. from seeds to the seedlings; the descriptive scale allowed evaluating the progression of RR symptoms; nine isolated of Fusarium spp. were found to be pathogenic to Pinus taeda seedlings, reproducing typical symptoms of RR, being isolated L3R2, the most aggressive and that exhibited higher AUDPC. © 2017, Universidade Federal de Santa Maria. All rights reserved.

The study aimed to investigate the influence of leaf temperature variation associated with irrigation suspension on gas exchange of seedlings of Sclerolobium paniculatum Vogel. The study was carried out in a greenhouse at experimental area of Embrapa, Amazônia Ocidental. Plants were grown in a greenhouse and, after four months were subjected to three treatments (irrigated maintained until the field capacity, irrigation suspended for eight and 14 days). We evaluated the physiological parameters of gas exchange, net assimilation rate of CO2 (A), leaf transpiration (E), stomatal conductance (g s) and water use efficiency (WUE) which were obtained through a photosynthesis portable meter (CI-340, CID, Inc). The results showed reduction of net assimilation rate of CO2 depending on the elevation of the leaf temperature and without irrigation. After eight days without irrigation, decreased rates of photosynthetic assimilation of CO2 in 62, 65, 75, 58, 50 and 64%, and after 14 days the reduction was 80, 85, 85, 84, 86 and 93% compared to plants irrigated maintained at temperatures of 25, 30, 35, 40, 45 and 50 °C, respectively. The leaf transpiration was inversely proportional to rates of net photosynthetic assimilation of CO2, which has increased with an increased leaf temperature. The physiological behavior of gas exchange of Sclerolobium paniculatum showed variations both as regards to the effect of leaf temperature as the suspension of irrigation. © 2017, Universidade Federal de Santa Maria. All rights reserved.

Ferreira B.G.A.,Federal University of Paraná | Zuffellato-Ribas K.C.,Federal University of Paraná | Wendling I.,Estrada da Ribeira | Koehler H.S.,Federal University of Paraná | Reissmann C.B.,Federal University of Paraná
Ciencia Florestal | Year: 2014

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.

Beckert S.M.,Federal University of Paraná | Rosot M.A.D.,Estrada da Ribeira | Rosot N.C.,Federal University of Paraná
Scientia Forestalis/Forest Sciences | Year: 2014

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.

Ferreira B.G.A.,Federal University of Paraná | Zuffellato-Ribas K.C.,Federal University of Paraná | Wendling I.,Estrada da Ribeira | Koehler H.S.,Federal University of Paraná | Nogueira A.C.,Federal University of Paraná
Ciencia Florestal | Year: 2010

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.

Ramos M.R.,CNPF | Curcio G.R.,Estrada da Ribeira | Dedecek R.A.,CNPF | Melo V.F.,Federal University of Paraná | Uhlmann A.,Estrada da Ribeira
Revista Brasileira de Ciencia do Solo | Year: 2013

The cohesive nature of horizons of certain soils interferes directly with plant growth, by reducing the effective soil depth, plant root volume and seedling emergence, due to the decreased availability of water and air in the soil. This paper aimed to use soil physical characteristics to describe the cohesive character and the influence of the soil landscape position on two slopesof soils developed from sediments of the Macacu Formation in Itaboraí, RJ, Brazil. The soils of both slopes were classified as Argissolo Amarelo distrocoeso típico (Ultisol) in the upper position and as Latossolo Amarelo distrocoeso típico (Oxisol) at the foot slope. The soil bulk density of the cohesive subsurface horizons reached 1.78 Mg m-3. Another evidence of the trendto show cohesive character was the great difference between soil physical propertiesofthe A horizon and the subsurface layers (BA and BW). In the soils at the foot slope position the moisture content, hydraulic conductivity, and available water content were higher. The expression of the cohesive character was stronger at the upper position of the landscape. The physical properties that best distinguished the soil samples in terms of landscape positions were bulk density and macroporosity for soils at the summits, and available water and total porosity for the foot slope. The soils at the bottom of the slope had higher water contents, which must have minimized the expression of the cohesive character. This study indicates the importance of developing more studies on different aspects of the degree of cohesion existing along a landscape, controlled primarily by water flows down the slope.

Commercial plantations of Ocotea porosa available for studying are scarce and therefore should be used as a source of information to establish the potential for management of the species in plantations, even if these evaluations were not been held along the stand development. The recovery of the historical growth of these stands to optimize the management plans is possible by dendrochronology and by the analysis of morphometric and dendrometric data. The aim of this study was to use stand analysis tools, combined with the dendrochronological studies, to recover and to systematize the development of unmanaged stands. The study was conducted in an unmanaged stand of Ocotea porosa, with with 44 years of age in Rio Negro, PR state, in a UFPR research station. Growth inferences recovered by dendrochronology and the competition by the application of methodologies such as rate of coverage and crown cover rate showed consistent results in the analysis of population, indicating the need for a first thinning near 12 years old. Due to the small number of sampled trees, the results do not allow any definitive generalization. However, they are consistent to establish an analysis protocol for unmanaged stands of Ocotea porosa or other species. © 2015, Universidade Federal de Santa Maria. All rights reserved.

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 | Year: 2013

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.

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 | Year: 2013

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.

Lazarotto M.,Federal University of Santa Maria | Muniz M.F.B.,Federal University of Santa Maria | Beltrame R.,Federal University of Santa Maria | dos Santos A.F.,Estrada da Ribeira | And 2 more authors.
Ciencia Florestal | Year: 2012

Researches about seed pathology of native forest species, especially, those more extensive, are rare. This research aims to evaluate the health of Spanish-cedar seeds through two detection methods, to evaluate the possible transmission of fungi associated to Cedrela fissilis seeds to seedlings and to evaluate the pathogenicity of the fungus transmitted by Cedrela fissilis seeds. For this, seeds from six different locations from Rio Grande do Sul, Santa Catarina and Paraná states were used. The seeds were submitted to sanity tests, by blotter-test and potato-dextrose-agar (PDA) methods, transmission by seeds to the seedlings and to the pathogenicity test of Rhizoctonia sp., chosen because it was common in sanity testing and transmitted by seed. The fungi found in both of the methods were: Pestalotia sp., Rhizoctonia sp., Penicillium sp., Phomopsis sp., Rhizopus sp., Aspergillus sp. and Fusarium sp. Both tests can be used for the sanity test in Cedrela fissilis seeds. The fungi transmitted by seeds to the seedlings were Fusarium sp. and Rhizoctonia sp., both causing problems in roots and subsequent damping-off. One of the isolates of Rhizoctonia sp. was identified as pathogenic to seedlings, causing the same symptoms observed on transmission test.

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