RCAAP Repository

The use of essential oil and extracts from plants is becoming an efficient alternative in the biostimulation on growth and protection of plants. The aim of this work was to evaluate the use of leaf essential oil of Eucalyptus grandis on the germination and the  development of Eucalyptus grandis seedlings in nursery conditions. The eucalyptus seeds were exposed to the concentrations of 0, 10, 25, 50, 75 and 100 μL L-1 of the essential oil in controlled conditions. The eucalyptus seedlings were sprayed with 0, 20, 30, 40, 50 and 60 μL L-1 of the essential oil per plant, at intervals of seven days. The effect of this application on the seedling development were analyzed after 30 and 60 days. The results show that the germination was significantly higher when the seeds were exposed to 25 μL L-1 of the essential oil. The application of essential oil in the concentration of 30 and 40 μL L-1 provided higher growth of the aerial part and of the roots in greenhouse conditions, being an effective alternative to biostimulation the vegetative growth of eucalyptus seedlings.

Forest species have great economic and social importance, offering various products as wood and non-timber fundamental to society. In this context, the search for new technologies that promote increase in productivity of commercial forests has received special attention and biotechnology has contributed substantially to this. This branch of science can promote direct modification of the genome of a target organism, through the analysis and manipulation of DNA genome or by insertion of fragments of the same with known function and thus to achieve desired characteristics, such as resistance to diseases and pests, lignin reduction in wood and generation of plants tolerant to different kinds of stresses. This review aims at reporting techniques for the generation of genetically modified trees, applications of genetic transformation in forest species, risks of using this technology and its potential environmental impacts.doi: 10.4336/2011.pfb.31.65.51

Soil is an important compartment of carbon in terrestrial ecosystem, retaining substantial quantity of this element in organic forms, mainly in forest areas. The understanding of the factors that affect the fluxes of soil CO2 is the basic to the reduction of emissions of greenhouse gases to the atmosphere. The objective of this work was to evaluate the patterns of spatial variability of soil CO2 flux in native forest in a very clayey dystroferric Red Latosol (Oxisol), in Lavras city, Minas Gerais state, Brazil. A grid of 32 points was delimited, regularly spaced in 5 m distance, in which the CO2 flux and environmental factors (water evaporation, temperature and soil moisture) and attributes related to fertility (pH, base soil saturation and exchangeable aluminium), structure (bulk density and total porosity) and soil organic matter (total organic carbon, microbial biomass carbon) were evaluated. Simple linear correlation analyses indicated that the soil CO2 emissions are a complex phenomenon, being not satisfactorily explained by a single soil or environment attribute. The CO2 flux did not present spatially structured variability in the adopted sampling scale, having a distribution that was considered as randomized. doi: 10.4336/2010.pfb.30.62.85

The objective of this research was to investigate the monthly growth rhythm of young trees of Araucaria angustifolia and Pinus taeda throughout the vegetative year and to establish its correlation with climatic variables. Monthly measurements of diameter and total height were carried out in one stand of A. angustifolia and two of Pinus taeda. Correlation matrices among the current monthly increments and the climatic variables indicated that the development of Pinus taeda is mostly affected by photoperiod and by minimum, average, and maximum temperatures, while A. angustifolia growth is affected mostly by minimum and average temperatures. doi: 10.4336/2010.pfb.30.62.165

Cnidoscolus phyllacanthus (faveleira), a caatinga xerophyte Euphorbiaceae tree, produces proteinrichforage consumed by ruminants. It should be used carefully due to urticaceous thorns in leaves, fine branches and fruits, and antinutritional substances present in fresh material. The narrow gene pool of the few thornless mutants should be widened by additional thornless individuals grown from open-pollinated seeds. This study checked the potential of six thorny and three thornless open-pollinated native trees in a caatinga site to produce thornless progenies, and estimated the proportion of their thornless progenies. The trial took place at the seed laboratory and seedling nursery facilities of UFCG/UAEF, Patos-PB, Brazil, from March 2002 to November 2003, in a completely random design with nine treatments (trees) and number of replications depending on seed and seedling quantity. Proportions of germinated seeds and thornless progenies were compared by the Student´s “t” test. Seven of the monitored trees produced thornless progenies (5.8% to 20.6%) consistently in two years.Three thorny and two thornless trees generated 15.1% to 20.6% of thornless progenies. Thornless progeniesshould be grown isolated to produce genetically improved seeds for the thornelss trait with a wide gene pool basis for distribution to local farmers and use to improve other traits such as forage and seed oil production. Further studies should investigate the genetic basis involved in the exhibition of this trait and if other trees in other C. phyllacanthus populations can produce thornless progenies as well.  doi: 10.4336/2010.pfb.30.62.147

Piptocarpha angustifolia Dusén ex. Malme (Asteraceae) is a brazilian native and pioneer tree species, occuring in Araucária Forest, with potential to ecosystem restorarion and introduction in forest, agriculture and pasture systems. Its propagation by seed presents irregular production and low number of feasible seeds while vegetative propagation by cutting of mature plants with semihardwood shoots didn’t present rooting response. This work aimed to evalue adventitious rooting by minicutting technique using minisprouts from seeds. The minisprouts were collected and dipped in ascorbic acid solution (1%) and minicuttings were produced with 5 cm lenght mantaining a pair of leaves in the apex installed in a medium with vermiculite and carbonized rice husk (1:1 v v-1). The evaluation was made after 90 days considering percentage of rooting minicuttings, number and lenght average for minicuttings, percentage of living minicuttings, percentage of minicuttings with callus and dead minicuttings. The higher production of minicuttings was verified in winter and spring, varying between 113.4 to 259.2 units for square meter a month. The adventitious rooting reached 45% in winter with 6.3 roots and an average of 9.8 cm of length, without using plant growth regulator.

The artificial defoliation allows to measure the defoliation intensity caused by insects. The objectives of this work were to evaluate the damages caused by leaf-cutting ants in young plantations of Pinus taeda and Eucalyptus grandis using different levels of artificial defoliation. A classification was established according to defoliation levels that were caused by leaf-cutting ants in P. taeda: level 1: 50%, level 2: 75%, level 3: 100% and level 4: 100%, including the cut of the apical meristem. And in E. grandis: level 1: 50% of defoliation; level 2: 75% and level 3: 100%. After one year, the P. taeda seedlings had losses in diameter and height for defoliation level above 75%. Seedlings severely defoliated (level 4), had losses of 37.0% in height and 45.4% in diameter. The E. grandis seedlings had losses since three months old and the reductions were proportional to the defoliation intensity. After one year, the losses of 13.3% in height and 20% in diameter were verified in plants with 100% of defoliation. P. taeda plants are more damaged by leaf-cutting attack.doi: 10.4336/2011.pfb.31.65.37

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This is the first record of the beetles attack (Curculionidae, Scolitinae) in neem plantations located in Brejinho de Nazaré, Tocantins, Brazil. The insects were observed on plants between 7 and 10 years old and were identified as Xylosandrus compactus (Eichhoff), Cryptocarenus diadematus Eggers, 1937 and Hypothenemus sp. Westwood, 1836. The attacked plants showed a growth rate considered low for the region, had a low seed production, high defoliation and branch sprouting, followed by the death of many young shoots and/or the tip of the branch. The insects caused intense gum exudation in the holes caused by them. This problem has similarities with the syndrome called "decline of neem", reported in Africa.

Carbon storage of agroforestry systems, regenerated areas, conventional agriculture and pasture was evaluated at Alto Ribeira Valley region, São Paulo State, Brazil, in different compartments of Land-use systems (LUS). In soil, classified as Entisols and Inceptisols, we found similarities among all LUS, dued to their low contents of organic carbon, and similar values of bulk density. The total carbon stocked on land-use systems, greater amounts were determined on regenerated areas (115.78 Mg ha-1), followed by agroforestry systems (75.38 Mg ha-1), agriculture (47.07 Mg ha-1), and pasture (36.01 Mg ha-1). Despite their conservative characteristic, the silvicultural practices of multistrata agroforestry systems have to be improved for forest production and carbon sequestration.doi: 10.4336/2011.pfb.31.66.143

The legal reserve (RL) is by the Brazilian Forest Code a portion of the total area of a farm where the use of the natural resources is to be done on a sustainable basis aiming the ecological processes, and biodiversity conservation and the shelter and protection of native fauna and flora.  The existence of RL has been criticized since its creation, specially by the allegation that it interferes on productive processes andfor regarding the difficulties of its implantation. The multistrata agroforestry systems (AFS) are widely accepted as a conservative management practice, even in Brazilian legislation, and it is an alternative technique for the  implantation of the RL. This work, carried altogether in small farms containing multistrata AFS and natural forests regeneration tracts (some of them already registered as RL) showed that this AFS, although productive systems, hold similar number and diversity of species to the renenerating forest , satisfying the legal minimum requisites expected in RL and thus suitable to be used as a technology for recovering and managing the RL. Moreover, as its management is agroecological, it was observed the recolonization of severalnative species, corroborating the potential use of these AFS in ecological restiration processes. Those agroforestry systems, however, need additional silvicultural practicesto improve forestry production and sustainability.doi: 10.4336/2011.pfb.31.67.203

Many governmental and non-governmental development organisations (NGOs) invest considerable efforts to support forest dependent people for the extraction and commercialization of non-timber forest products (NTFP) to generate income in an ecologically sustainable way. But success so far has been quite modest. Many of the families abandon these initiatives once the external support ceases. This paper critically reflects on the expectations and concerns regarding this kind of development projects by in-depth analysing a project for the commercialization of vegetal oils by the traditional community of Pedreira, situated in the Eastern Brazilian Amazon, which received intensive government-lead support. The study explores the motivations of the participating families, how the project influenced production schemes, and what have been the specific benefits for participating families and the overall consequences for the entire community. Findings indicate that the analyzed NTFP project, on the basis of overoptimistic expectations, strongly invested in the re-organisation of local production schemes without adequately considering the socio-environmental reality, capacities and interests of the community. As a consequence, the proposed social-productive model was not necessarily meaningful to all local people and even had detrimental effects.

The objective of this work was to fit the probability density functions Normal and SB, to describe the changes, with age, in the diameter distribution of loblolly pine (Pinus taeda) stands, in the region of Caçador, Santa Catarina State, Brazil. The data came from permanent and temporary plots, with ages ranging from 5 to 11,9, grouped in age classes with intervals of 1 year. The probability density functions were fitted and, the Kolmogorov-Smirnov test and the parameters of skewness and kurtosis were calculated. Basing on Kolmogorov-Smirnov test it was verified that, for ages from 5 to 7.9 years old, the Normal and SB functions didn’t show satisfactory adherence. The SB and Normal functions showed better adherence to the ages from 8 to 9.9 and from 10 to 11.9 years old, respectively. Using the Normal probability density functions to analyze the dynamics of the diameter distribution, it was found that there was a shift of the diameter distribution curves to the right, a “flatness” and an “wideness” of these curves, over the years. The skewness was negative for all ages, except for the age from 8 to 8.9 years old. The kurtosis was leptokurtic for all ages, except for age from 8 to 8.9 years old, which was platykurtic.

A study of the grasshopper fauna was performed through samples collected in three vegetal types in the National Forest of Chapecó. Weekly collections were carried out from December 2003 to December 2004. Pitfall traps, sweep nets, entomological umbrellas and malaise traps were used. Collections were repeated in areas with eucalyptus trees, native species and pine trees. The fauna found in different areas was classified by its abundance, constancy, dominance and frequency. Eighteen species were common in the three areas. Staurorhectus longicornis longicornis, Cylindrotettix sp. and Ommexecha virens were found only in eucalyptus and pine areas. Scotussa lemniscata and Zoniopoda tarsata were found in areas with eucalyptus and native trees. Amblytropidia sp. was found only in native vegetation and pines areas. Tridactylus politus was found just in the pine area. Allotruxalis gracilis, Dichroplus elongatus, Dichroplus misionensis and Ronderosia bergi were very frequent, dominant and very abundant in the eucalyptus tree area. A. gracilis, M. adspersa and D. misionensis were very frequent, dominant and very abundant in the native tree area. Metaleptea adspersa and R. bergi were very frequent, dominant and very abundant in the pine area. A similarity in diversity of species was verified with greater abundance in the eucalyptus area.doi: 10.4336/2011.pfb.31.65.43

Eucalyptus benthamii has shown to be the most proeminent specie for regions with frost incidence. The objective of this work was to classify selected Eucalyptus benthamii trees for breeding by importance ordening dendrometric and energetic characteristics, useful for this work 91 disks of DBH were collected, from three plantations at Guarapuava municipality, Parana state, with geographical coordinates 25º 23’ 26’’ S e 51º 27’ 15” E and 1,120 m high. Wood basic density, volume, mass, superior calorific power, energertic density and energetic potential were evaluated. Charcoal yield, condensed and non-condensable gases, fixed carbon, volatiles, ashes, superior calorific power and energetic potential were also evaluated. From the measured characteristics, at the field and laboratory for each individual, multivariable analysis were performed using the main compounds and factorial analysis with the aim of identifying those variables which presented larger contribution for total variance. At E. Benthamii tree selection for energy production, most of the attention should be driven to the variables mass, volume, wood energetic potential and charcoal energetic potential.doi: 10.4336/2010.pfb.31.65.09

The objective of this research was to quantify the genetic dissimilarity among P.caribaea var. caribaea progenies to identify divergent parents aiming to generate highly productive genotypes and to evaluate the total variability by phenotypic characters of commercial importance. The progeny trial of P. caribaea var. caribaea was set up through 10 x 10 triple lattice design, with 99 progenies and a commercial control in Selvíria, MS, Brazil. We have evaluated quantitative characters before and after thinning procedures such as: total plant height (m), diameter at breast height (dbh) (cm); wood volume  (m3 tree-1), stem form, wood density at dbh and wood density at the middle of the total height of tree stem (g cm-3), and survival of progenies (%). There was low genetic divergence among P. caribaea var. caribaea progenies. The diameter at breast height was the character that most contributes to genetic diversity among progenies, for both before and after thinning. The information of Mahalanobis distance and the clustering of progenies by Tocher's method will be important to define the future strategies for breeding programs and genetic conservation of the species. doi: 10.4336/2012.pfb.32.69.69

The understanding of wood quality in relation to different forest sites is of fundamental relevance in current timber market. There are only few studies available concerning soil and wood quality of tropical pinots. So, the goal of this work was to characterize tracheid dimensions and wood density of Pinus caribaea var. hondurensis, correlating these variables with soil properties at different sites. Discs were taken at 1.3 m height and comprised two radial samples in each of the four dominant trees removed at four different sites. Measurements for wood density were made from the third to the eleventh year old rings, and the measurement of tracheid dimensions were made in the fourth, eighth and eleventh year sold rings. The soil, collected in the canopy projection area of each tree was analyzed chemically and physically in different layers. The tracheid dimensions and wood density showed stabilization between the eighth and the eleventh years old rings. Moreover, the tracheid dimensions varied between sites and did not present a pattern of variation in relation to soil properties at the different sites.

The aim of this experiment was to evaluate the best concentration  and the incubation time to test germination in seeds of  Anadenanthera peregrina (L.) Speg. The seeds were  preconditioned at 25 ºC for 14 hours immersed in distilled water.  The coat were removed and the embryos submerged in tetrazolium solution (pH 6.5) solution in the concentrations of  0.1%; 0.05% and 0.01%, being kept in dark at 25 ºC for three and five hours and at 30 ºC for 24 hours. It was evaluate the intensity and localization of the coloration, presence of milky areas, tissues aspect. The embryos were classified in nine classes of viability. The best treatment as substitute of the germination test was the 0.1% tetrazolium incubated at 30 ºC for 24 hours. Viable seeds of A. peregrine were classified in classes 1, 2 and 3.doi: 10.4336/2011.pfb.31.67.269