Top 10 - December

1-FLORISTIC COMPOSITION AND SPECIES ABUNDANCE DISTRIBUTION IN TWO TERRA FIRME AREAS IN AMAZON

Ana Maria Moreira Fernandes,  Maria  de  Lourdes  Pinheiro  Ruivo,  Antônio  Carlos  Lola Costa

Abstract

The studies on floristic composition are an aid in the understanding of the structure and dynamics of the plant communities, fundamental parameters for its management and conservation. Thus, the objective of this work was to evaluate the floristic composition, species richness, Shannon’s diversity and models of species abundance over a 10-year period (2005 to 2015) in two terra firme forest areas, with and without water deficit in the  soil.  Data  were  collected  in  98  subplots  denominated  A  (control)  and  98  subplots  B (rainwater exclusion), each measuring 10 m x 10 m, of which plants species with diameter at breast height (DBH≥10 cm) were listed. The Fabaceae (33), Sapotaceae (27), Chrysobalanaceae (15) and Burseraceae (13) families were the most representated in the study areas. A small decrease was found in the observed species richness in area A, but the community evenness and the Shannon diversity index remained constant, and a small increase was found in the observed species richness  in area B, which may have contributed to a increase in the diversity index over time. The Zipf and Zipf-Mandelbrot models adjusted for the plant communities of areas A and B, respectively, indicate that such areas indicate good ecological conditions for the establishment of late colonizing species. Thus, it can be inferred that water deficiency in the soil did not significantly affect the conservation of the forest under study. 

Keywords: Diversity, Richness, Rainfall exclusion

 

2-EVALUATION OF THE CONSERVATION STATUS OF Dalbergia nigra (Vell.) Allemão ex Benth BY ANALYSIS OF DIVERSITY AND GENETIC STRUCTURE

Adelson  Lemes  da  Silva  Júnior,  Rafael  Lara  Rezende  Cabral, Lara  Sartori,  Lucimara  Cruz  de  Souza,  Fábio  Demolinari  de  Miranda,  Marcos  Vinicius  Winckler  Caldeira, Sarah Ola Moreira, Tiago de Oliveira Godinho

Abstract

The evaluation of diversity and genetic structure allows us to verify with precision the effect of evolutionary and anthropic processes on species. The objective of this research was to evaluate the divergence and the genetic structure of two natural populations of Dalbergia  nigra,  using  molecular  markers  Inter  Simple  Sequence  Repeats  (ISSR).  Leaf samples were collected from two populations, located in the National Forest of Pacotuba and the Private Natural Heritage Reserve of Cafundó. Eight ISSR primers were used, which resulted in 97 bands, with 68.04% of polymorphism. Based on the joint data, the values of 0.33 for the Nei index (H*) and 0.50 for the Shannon index (I*) indicated moderate to high genetic diversity, being influenced by the presence of genetically dissimilar individuals in the National Forest of Pacotuba. Most of the genetic  divergence  was  intrapopulational  (85.96%),  with  moderate  differentiation  between  populations  (ΦST = 0.1404). The estimated historical gene flow between the  fragments  was  low  (Nm  =  3.21)  when  compared  with  results  from  other  tree  species,  and  the  genetic  structuring  analysis  separated  the  populations  into  two  groups, corresponding to the two populations evaluated. The results indicate a small genetic  share  among  populations,  however,  populations  are  becoming  structured.  The satisfactory levels of genetic diversity benefit the use of the trees as matrixes for programs of restoration and recovery of degraded areas, connectivity of landscapes, and sustainable use of forest resources.

Keywords: Brazilian rosewood, Forest conservation, ISSR, Molecular marke

  

3- THE USE OF GENETIC DISTANCE AND GROUPING METHODS TO PREDICT Eucalyptus pellita F. MUELL GENITORS FOR HYBRIDIZATION

Mateus Chagas Andrade, Aline Cristina Miranda Fernandes, Leandro de Siqueira, Evandro Vagner Tambarussi

Abstract

The objective  of  this  study  was  to  use  quantitative  traits  to  estimate  the  genetic  distance  among E.  pellita  provenances  and  progenies,  to  inform  possible  hybridization  strategies  in  a species improvement program. A provenance and progeny test with 118 progenies from seven provenances was evaluated. The following quantitative traits were measured at seven years of age: diameter at breast height (DBH); height; and individual volume. The data were submitted to REML/BLUP analysis to obtain the predicted genetic value (BLUP). From this, the Mahalanobis (D²) genetic distance was estimated for provenances and progenies, which were then grouped by Tocher’s method, the unweighted pair group method using arithmetic averages (UPGMA), and principal component analysis (PCA). In total, 29 divergent groups were obtained among progenies based on Tocher’s method, which showed greater reliability according to the cophenetic correlation coefficient than UPGMA. The opposite was found between provenances, where the results for UPGMA demonstrated greater clustering relia-bility. Based on principal component analysis (PCA), the M. Ray and Tully provenances were the most similar, while Connl. A and Orchard were the most divergent. Height was the most important trait in estimating genetic distance. The results obtained offer important insights for breeding programs; with this information, crosses can be designed between contrasting individuals among and within provenances to obtain E. pellita hybrids, validating the possible heterotic groups identified through the genetic distance and grouping methods.

Keywords: Multivariate analysis, Forest improvement, Heterotic groups, Hybrids

  

4- CLIMATE ZONING  FOR  THE  CULTIVATION  OF  AFRICAN  MAHOGANY  SPECIES IN BRAZIL

Rodrigo de Sousa Oliveira, Túllio Morais Franca

Abstract

African mahogany is the common name given to different species of the genus Khaya. They are  tree  species  native  to  the  African  continent,  which  have  a  wood  quality  that  allows  their noble use in making fine furniture, and in the civil and naval industries. Currently, African  mahogany  cultivation  has  received  notoriety  in  Brazil  and  given  its  climatic  conditions.  The  country  has  great  potential  for  planting  these  species.  The  purpose  of  this work was to identify climatic aptitude zones for African mahogany in Brazil. Based on the Kppen classification and in the means of relative air temperature and annual rainfall, a  base  map  interpolation  was  performed  to  select  regions  suitable  and  restricted  to  planting and adequate growth of African mahogany species. In general, the regions that presented temperatures between 22 °C and 30 °C were considered of high fitness, while temperature values below 14 °C restricts plantations growth. Regarding to precipitation, areas considered to be of high aptitude have between 700 to 3,000 mm.year-1, extreme values may indicate regions of low suitability and restricted to the cultivation of African mahogany.  From  the  climatic  characteristics,  it  was  determined  that  about  60%  of  the  Brazilian area was of high fitness, between 16% and 32% of medium fitness, and less than 20% as low fitness. The Northeastern semi-arid region proved to be restricted to the cultivation of these species due to the low annual rainfall and a few places in the South region was also restricted due to low temperatures and risks of frost.

Keywords: Climatic aptitude, Khaya,  Rainfall,  Temperature

 

5-CHARACTERIZATION OF INJURY  CAUSED  BY  Coptotermes  testaceus IN Tectona grandis PLANTATIONS IN BRAZIL

Jerffersoney Garcia Costa, Isabel Carolina de Lima Santos, Otávio Peres Filho, Ronald Zanetti, Alexandre dos Santos

Abstract

Coptotermes  testaceus  (Linnaeus,  1758)  is  the  most  important  species  of  heartwood  termite  of  adult  trees  in  forests  planted  in  Brazil.  This  study  aimed  to  characterize  the  injuries promoted by the heartwood termite C. testaceus in Tectona grandis commercial stands. Tree bark with extend carton material on the outside, forming external galleries and  internal  stem  with  a  high  termite  infestation,  was  found  in  August  2018,  in  clonal  plantations of T. grandis of 4.2 and 7.2-year of age. Internal injuries were characterized by galleries inside stem length with the presence of some soil, carton material, and termites inside  the  galleries.  The  damage  by  C.  testaceus  may  not  show  external  signs,  and  the  injury was only detected during the harvesting process.

 Keywords: Forest entomology, Heartwood térmites, Rhinotermitidae, Teak, Termite

  

6-MECHANICAL  AND  PHYSICAL  PROPERTIES  OF  WOOD/POLYETHYLENE  COMPOSITE REINFORCED WITH TIO2  NANOPARTICLES

Mohammad Dahmardeh Ghalehno, Behzad Kord, Babak Nosrati Sheshkal

 Abstract

Wood  plastic  composite  was  fabricated  using  high  density  polyethylene  and  pine  wood  fiber. The effect of addition of TiO₂ nanoparticles at different weight fractions (0%, 1%, 3%,  and  5%)  on  some  properties  of  the composite  was  examined.  The  experimental  composites  were  tested  for  bending  strength,  tensile  strength,  Izod  impact  strength,  thickness  swelling,  and  contact  angle.  Field  emission  scanning  electron  microscopy  was  also  investigated  to  study  the  distribution  of  TiO₂  nanoparticles  in  the  composites.  The results showed that using TiO₂ nanoparticles as a reinforcing agent in wood plastic composites resulted in an increase in the tensile and bending strengths and a decrease the thickness swelling of the composites. The effect of TiO₂ nanoparticles on the Izod impact strength of composites was not significant. The results also showed that the contact angle of wood plastic composites was improved by using TiO₂ nanoparticles.

Keywords: Wood/polyethylene composite, TiO₂, Nanoparticles, Mechanical strengths,  Thickness swelling,Contact angle

 

7- ACCURACY OF GENETIC PARAMETERS ESTIMATION AND PREDICTION OF GENOTYPIC VALUES IN EUCALYPTUS USING DIFFERENT PLOT TYPES

Marcos  Rafael  Amâncio,  Mateus  Chagas  Andrade,  João  Gabriel  Zanon  Paludeto, Matheus  Perek,  Odair  Bison,  Amanda  Roberta  Vergani,  Andrea  Nogueira  Dias, Evandro Vagner Tambarussi

Abstract

A  suitable  experimental  design  should  control  the  environmental  effect  and  be  capable  of discriminating genotypes. Two clonal tests of Eucalyptus were planted side by side in a randomized block design with the same 32 treatments under two different plot designs. The first trial was designed with five plants per plot (linear plot, LP) and six block replicates at a spacing of 3 x 2 m. The second trial was designed with one plant per plot (single-tree plot, STP) and 30 block replicates also at a spacing of 3 x 2 m. Diameter at breast height (dbh), height (h), and individual volume (vol) were measured at five years of age. The STP design  presented  broad-sense  heritabilities  values  of  0.23  for  h  and  0.41  for  vol,  which  were higher than those found for the LP design (0.12 for h and 0.22 for vol). The ratio between the standard error and the estimated genotypic variance (gS) was lower for the  three  evaluated  traits  in  the  STP  trial.  The  correlations  between  the  genetic  values  were positive and of high magnitude, ranging from 0.87 (h) to 0.91 (vol), but there were many differences between the two designs with regard to the ranking of clones. The STP presented  better  discriminant  power  according  to  the  biplot  analysis,  as  well  as  more  accurate and reliable estimates.

Keywords: Single tree plot, Linear plot,  Clonal test,  Standard error,  BLUP

 

8- ALTERNATIVES  TO  ESTIMATE  THE  VOLUME  OF  INDIVIDUAL  TREES  IN  FOREST FORMATIONS IN THE STATE OF MINAS GERAIS, BRAZIL

Jadson Coelho de Abreu, Carlos Pedro Boechat Soares , Helio Garcia Leite, Daniel Henrique Breda Binoti, Gilson Fernandes da Silva

Abstract

The  objective  of  this  study  was  to  compare  different  alternatives  to  estimate  the  stem  volume  of  individual  trees  in  four  different  forest  formations  in  the  Minas  Gerais  state,  Brazil. The data were obtained in a forest inventory procedure performed by the Minas Gerais  Technological  Center  Foundation.  The  stem  volumes  were  computed  by  the  Smalian expression up to the outside bark diameter equal to 4 cm. The volume data of outside bark, diameters (DBH) and total heights were used to fit a Schumacher and Hall equation for each forest formation, considering the structures of the linear fixed and mixed models. Next, 100 Multilayer Perceptron artificial neural networks (ANN) were trained in a supervised manner. In addition, we evaluated eight support-vector machine regression (SVMR). The criteria to evaluate the performance of all the alternatives studied were: the correlation between the observed and estimated volumes, the square root of the mean square error and the frequency distribution by percentage relative error class. After the analyzes, all the alternatives were verified to estimate the volume of the individual trees in the different forest formations. Although the alternatives presented close statistics in the  validation  process,  the  graphical  analysis  of  the  error  distribution  showed  greater  precision of the estimates of the mixed linear models for the four formations. Given the results,  it  is  concluded  that  there  is  no  absolute  superiority  of  one  alternative  over  the  others, and that all of them should be evaluated to find the one which best describes or explains the dataset.

Keywords: Artificial neural networks, Mixed linear model, Regression, Support-vector machine

 

9- MINI-CUTTINGS TECHNIQUE  FOR    VEGETATIVE    PROPAGATION    OF    Dalbergia nigra

Aline Ramalho dos Santos, Elzimar  de  Oliveira  Gonçalves,  Elbya  Leão  Gibson, Emanuel  França  Araújo,  Ivar  Wendling,  Lara  Arêas  Tertuliano,  Marcos  Vinicius  Winckler Caldeira

Abstract

The usual propagation method for Dalbergia nigra is via seedings; however, the seasonal supply has a variable quantity of seeds which limits the continuous production of seedlings. Therefore, the objective of this study was to establish a vegetative propagation protocol via mini-cuttings technique for D. nigra from juvenile shoots obtained from seedlings. The experimental design was completely randomized in a 2 x 2 x 4 factorial scheme, with two geographical origins: two controlled release fertilizer doses (4.0 and 8.0 g.dm-³) and four indole-3-butyric acid (IBA) concentrations (0; 2,000; 4,000; and 6,000 mg.Kg-1), with four replications. The mini-cuttings were removed from the tubes after 60 days of propagation in  the  greenhouse,  and  the  substrate  was  completely  removed  by  washing  in  running  water to observe the roots. The survival percentage, rooting, rooting speed and variables related to mini-cuttings vigor (largest root length (RL, cm.plant-1), number of roots (NR), surface area (SA, mm2), root volume (RV, mm³) and root dry mass (RDM, g.plant-1) were measured. The results indicated that D. nigra has an aptitude for vegetative propagation by mini-cuttings with survival values and rooting greater than 70%. Geographical origins present a different set of responses for survival, rooting and vigor of mini-cuttings. Stock plant nutrition influences mini-cuttings root growth. IBA concentrations did not promote an  effect  on  the  mini-cuttings  rooting  percentage;  however,  exogenous  auxin  at  the  dose of 6,000 mg.Kg-1 provided mini-cuttings with greater vigor in their radical system. Nonetheless, further research is suggested to define the feasibility of using this regulator in the vegetative propagation of this species.

Keywords: Conservation,  Clonal forestry,  Adventitious rooting,  Forest nutrition,  Geographical origin

 

  

10- THE  EFFECT  OF  ALTITUDE  ON  THE  GROWTH  AND  DEVELOPMENT  OF  TROJAN  FIR  (Abies  nordmanniana  subsp.  equi-trojani  [Asch.  &  Sint.  ex  Boiss]  Coode & Cullen) SAPLINGS

Seray Özden Keleş

Abstract

The altitude is an important factor to affect the growth and development of saplings of the tree.  However, the effect of altitude on the growth and properties of wood during their young stage it has been little studied. This study, therefore, aimed to evaluate the influence of two different altitude steps: 795 m (a.s.l. low-altitude) and 1350 m (a.s.l. high altitude)  on  the  morphological,  anatomical  and  wood  density  properties  of  saplings  of  Abies  nordmanniana  subsp.  equi-trojani [Asch. & Sint. ex Boiss] Coode & Cullen (Trojan fir). Trojan fir is an endemic species in Turkey and its morphology and anatomy have less studied in the literature. The functional traits and wood density properties differed significantly  between  the  two  altitudes.  The  saplings  grown  at  low-altitude  showed greater taper degree, pith radius, pith proportion, and bark proportion than high-altitude. However, stem height, stem diameter, node number, and xylem proportion were found to be higher in saplings grown at high-altitude than low-altitude. Wood cell anatomy also varied significantly between two altitudes such that ring width, ray numbers, tracheid length,  and  tracheid  width  were  higher  at  low-altitude,  whereas  ray  height,  ray  width,  tracheid lumen width, and tracheid wall thickness were greater at high-altitude. This study, therefore, suggested that the growth and development of fir saplings were better when they were grown at high-altitude than low-altitude.

Keywords: Altitude, Sapling, Trojan fir, Stem Morphology